Question 1

Arched Windows - What are the shading options ?

Accepted Answer

Horizontal mini blinds
The most practical type of blind for arch windows or windows with an arched top is a horizontal mini Venetian type. Techform mini blinds are available in a wide range of aluminium and timber slats. This range uses conventional Venetian blind design head-rails and operating mechanisms and are retractable as far as the shape allows. They hang in the window in the same way as a conventional blind does.

Non-Retractable Blinds
For large windows non-retractable louvre blinds are more practical. They have an aluminium framework that extends at intervals down the length of the blind and is thus tilt only and non-retractable. It is the most robust option for shaped windows and sloping glazing. More here

Vertical louvre blinds
Suitable for shallow arches and where there is space at the side for the louvres to stack (ie no cill). Where there is a cill only tilt operation is possible. Not recommended when the depth of the arch is more than half of the width. More here

Pleated Blinds
We consider this to be a domestic solution unsuited to contract applications. The blind is fitted on one radius of the arch and is fanned round with support cables. Only suited to small windows. More here

Roller Blinds
The roller would be mounted at the cill. The centre of the fabric needs to be reinforced to allow a centre draw. This causes strain on a small area of the cloth and inadequate support at the sides which will sag. For arch tops reinforcing with PVC piping around the arched part of the cloth will strengthen the edges but prevent it from retracting around the roller. Thus the blind could only be lowered as far as the arch part. This is not an option that we would recommend.

Question 2

Atria - What are the shading options ?

Accepted Answer

As the areas are generally higher and access more difficult for maintenance we would only recommend our Techtonic tilting louvre options. More here The reasons are the same as those given for what are the requirements for shading a conservatory roof or sloping glazing only more so because the scale and height are generally greater exacerbating the problems.

Why not retracting blinds?
Retracting roller blinds traversing across relieving rollers with tensioned cables to draw and guide them are fine in theory. That is until the tension slackens or something else causes them to jamb and then hope that no one is the way if the tensioned cable snaps and gracefully flicks through the air cutting anything in its path!

Question 3

Circular Windows - What are the shading options ?

Accepted Answer

Horizontal Mini Blinds
The most practical type of blind for circular windows is a horizontal mini Venetian type. Techform mini blinds are available in a wide range of aluminium and timber slats. This range uses conventional Venetian blind design head-rails and operating mechanisms and they hang in the window in the same way as a conventional blind does.

Non-Retractable Blinds
For large windows non-retractable louvre blinds are more practical. They have an aluminium framework that extends at intervals down the length of the blind and is thus tilt only and non-retractable. It is the most robust option for shaped windows and roof-light glazing. More here

Vertical louvre blinds
Suitable for shallow arches and where there is space at the side for the louvres to stack (ie no cill). Where there is a cill only tilt operation is possible. Not recommended when the depth of the arch is more than half of the width.

Pleated blinds
We consider this to be a domestic solution unsuited to contract applications. The blind is fitted on one radius of the arch and is fanned round with support cables. Only suited to small windows.

Question 4

Awnings - Will I need planning permission to fit an outside blind?

Accepted Answer

Unless it is a listed property the answer is no provided that it is retractable and not a fixed structure. If it is a listed property or in a conservation area our advice is to ask the local planning officer.

Question 5

Black Out/Dim Out Blinds - What type do I require ?

Accepted Answer

If you are doing light sensitive experiments or photographic processing choose a room without a window or brick it up!

The fabric of a blackout blind will be 100% blackout but for a retractable system total blackout is exceedingly difficult to achieve and for almost all purposes is unnecessary.

When the blind is first pulled down the blind can appear as 100% blackout. But the human eye will adjust to the changed light levels. To test 100% blackout to EN BS 14500 in a darkened laboratory the operator has to assimilate to the conditions for 15 minutes from the time the blind is lowered.

At this time the slightest pin prick of light will become a bright beam. There are 3 levels of light intensity simulated from the adjacent test room to determine a standard.

The principal is the same as when you are in an aircraft with a darkened cabin and a car or street light from several miles away can be clearly seen.

But is 100% the requirement? In fact in some circumstances, public circulation areas such as a gallery for example, total blackout could be a hazard

What are the options?
Roller dark blinds with side guides and boxing and 100% blackout Fabric. More here

Roller dim out blinds with 100% blackout fabric and side masking. More here

Roller dim out blinds without side masking

Roller blinds with a dark/dense fabric

Venetian blinds AV with side masking. More here

So what type of blind is really needed?
The main reason for using boxed blinds is that the use of a 100% blackout fabric highlights the light sources at the edges.

The extent to which you need to solve this light seepage is one of the main issues. Boxing and side channels add significantly to the cost so when should they be considered?

1. The boardroom or lecture theatre.
 If ease of operation and aesthetics are the main concern consider electrically operated boxed blinds. Control of all blinds from one position and guides and boxing for neatness of appearance. More here

2. School Physics lab with light experiments
Function dictates that boxed blinds are required and cost that manual operation is adequate. More here

3. Other school labs and AV rooms. 
Function and cost suggest dual function Audio visual Venetian type Classic AV or manual dim out roller blinds possibly with side guides

4. Conference room that already has sunblinds

Occasional AV use - cost and function. Easi-roll roller blinds with blackout fabric Gear operated or Easi roll fitted outside the reveals wider than the window using the walls as side masking or Venetian type with privacy slats.

So assess the priorities:- function, ease of operation, aesthetics, cost and that determines the solution
A definition of the standards for light exclusion can be found in BS EN14501.

Other possibilities:
Blackout curtains. Curtains lined with a blackout fabric with 100% fullness are an alternative to boxed blinds that when fitted full height outside the window can be almost as effective in light exclusion.

Blackout Roman blinds –an alternative to dim-out roller blinds at a higher cost VR110 Shutters. Will provide a good degree of dim-out when closed and also have the benefit of their normal functions for security and privacy.

Roof-light blinds or blinds to sloping glazing. – whilst roller type are possible we only recommend Techtonic non retractable louvre type link except for photographic studios where Roof-light roller blinds are the only option. More here

Question 6

Child Safety: What are the requirements for blinds fitted in areas used by young children

Accepted Answer

As members of the British Blind and Shutter Association (BBSA) we fully support the BBSA’s make it safe campaign.

Since the start of the campaign we have been supplying safety devices to areas where children or vulnerable people may be present. In early 2014 legislation came into force that enforced standards for all new blinds. It is now an offence to fail to fit safety devices if the product requires them in any domestic property and commercial buildings where children under that age of 42 months may be present.

Our recommendation when purchasing new blinds is that you select inherently safe product.
The BBSA’s recommendations to parents and carers are:
• Do not place a child’s cot, bed, playpen or high chair near a window so they may reach a blind cord
• Do not place furniture near a window that a child could climb on to reach a blind cord
• Do make sure that a safety device is fitted to keep the cords taut or out of reach
You can download a copy of the BBSA’s make it safe brochure. More here

Parents and carers are reminded that:

“Complete elimination of the strangulation risk can only be achieved by keeping cords, chains, and tapes and similar out of the reach of children. Use of additional safety devices may reduce the risk of strangulation but cannot be considered fool proof ……Persons in charge of children are ultimately responsible for following the safety instructions provided by the manufacturer.” EN 13120 – Internal Blinds Performance requirements including Safety.”

This is not a theoretical hazard several cases of tragic fatalities have occurred in the UK in recent years.
Whilst compulsory changes to the standard will resolve the problem with new product the hazard still exists with the millions of blinds that were installed before the problem became apparent. Fortunately in most situations safety devices can be retro-fitted.– don’t take a chance, make it safe!

The child safety legislation is not retrospective so there is no legal requirement to make them safe. BUT if you are the owner of premises such as hotels, guest houses, nurseries, tenanted properties or any other place where children under 42 months frequent then you have a duty of care.

What should I do with existing blinds?

Simple devices can make existing blinds safer.
That does not mean that you have to comply with legislation it is simply taking sensible steps to minimise the risk.

Cords should be shortened so that, where possible, they are at least 1500mm from the floor. BUT do not cut them before making sure that you can reach them and that the blind will open and close at the shorter length.

For looped cords fit a safety cleat and, where possible, 1500mm from the floor
For looped chains “P clip” cleats are available to secure to the wall. Breakaway connectors can also be fitted but check before cutting the chain to fit them that the position will not interfere with the operation. Ideally fit two at least 150mm apart as there are certain positions where one will not work.

The objective is to take sensible steps to minimise the hazard of looped cords and if you are not the user or occupier make sure that the person responsible is aware of the hazard.

AWARENESS is the most important safety measure. Safety devices that are fitted and not used will not help.

Question 7

Roller blind - What can I do if my blind rolls off line?

Accepted Answer

If your roller blind cloth rolls across to one side of the roller it will touch the brackets and fray. Fraying will increase the roll build up and make the situation worse.

To correct it pull the blind down past its full drop until you can see the roller. Place a piece of folded paper (called a chip) under the roller on the side opposite from the side that the cloth is moving towards the bracket. This will build up the roll on that side. Raise the blind and it will roll nearer to being square.

Adjust the chip until the blind rolls correctly.

Question 8

Roller blinds - Can they be made to draw sideways ?

Accepted Answer

Except for small tambour shutters that are used in office furniture side draw will not work. For a roller blind, however it is guided, gravity will cause the cloth to roll down to rub against the lower bracket and fray the cloth.

Question 9

What are the requirements for shading a conservatory roof or sloping glazing ?

Accepted Answer

The saying goes that people that live in glass houses should not throw stones – but they should also not be surprised if they get hot!

The science is this - The suns rays are not hot. In the spectrum most that prenetrate the atmosphere are short wave (that is light) and are cold until they come into contact with an object. That is when they change wavelength and convert into long wave radiation, that is heat.

On the beach that is you. Some of the energy is reflected and some is absorbed by your body.
The same happens in a window. Some solar gain is reflected by the glass, some is absorbed and some is transmitted through. Of the absorbed energy some is reflected but most is transmitted into the room.
When the transmitted energy reaches an object in the room, say the wall, some is absorbed heating the wall and some is reflected back to the glass. Glass is opaque to long wave radiation so it cannot pass back through it and is retained in the room as heat. This is known as the greenhouse effect.

An internal blind will have the same effect. Some heat will be transmitted through it, some will be absorbed and some reflected back to the glass. Generally the lighter the colour of the fabric the more it will reflect back. Except that, because most has changed wavelength, only a certain amount will pass back through the glass. The remainder will be trapped as hot air between the blind and the glass.

If it is not vented it will build up and as the blind heats it will be transmitted into the room.
For the most effective reduction in solar gain external shading should be selected. Most of the heat that is transmitted through or absorbed by the external blind changes wavelength and then will not pass through the glass.

It becomes trapped between the blind and glass and - natural science again - as hot air rises convection draws cooler air in at the bottom and draws the heat upwards between the blind and the glass and vents it out at the top.

For internal blinds to work effectively, where external blinds are not practical, an extractor or opening light at the top will be needed to remove the heat build up between blind and glass. Effectively venting the hot air will prevent the blind from becoming a radiator and whilst it will still not be as effective as an external system will significantly improve the amount of heat rejected.

As a generalisation a material that rejects 40-45% of solar gain internally would reject 85-90% fitted externally.

External blinds are the most effective – where internal blinds are the only practical option extractors or vents will improve their performance.

Our Techtonic range has options for both internal and external shading. More here for internal - More here for External

Question 10

Doors - How do I fit a blind to one ?

Accepted Answer

The issues are:
1. Is there enough clearance for the blind and fittings when the door is opened
2. How do you stop it moving about
3. will the blind clear the door handles and closers
4. how do you fit to an all glass door
5. what types of blinds are suitable

The most basic yet often the best is a roll up fabric blind that is often used in schools. As there are no mechanisms it is the least prone to damage and as it has a depth of only 10mm overcomes the problem of being knocked off if the door is opened sharply and is child safe. More here

Mini or micro Venetian type can be secured with either bottom rail hold down brackets or side guide cables. They need a minimum clearance of 45mm to the wall when the blind is open. More here

A neater child safe option for UPVC windows is a framed system Perfect Fit. The frame is secured with clips that fit between the window frame and glass and avoid the need for any drilling or fixing into the window. More Here

Self acting spring roller blinds can be secured with a turn button or cleat but need a clearance of 50mm when the door is opened. More here

Glass doors
Brackets are available to clamp to the top of the door providing that there is clearance at the top for the thickness of the brackets.

Question 11

Rooflight Blinds - What are the options?

Accepted Answer

It depends on what you need the blind for. If it is to reduce solar gain then an external blind may be necessary. If your requirements are for glare, light control or privacy an internal system will be the most suitable.

The options are listed but some selection points to consider are detailed in what type of blinds do I need in a conservatory More here

Non-retractable Louvre Blinds
Techtonic or Tetrix systems will tilt only to adjust light levels and control glare. Both systems can be mounted externally where they are most effective in reducing solar gain. For most uses an angle will be found that balances the need for glare and heat gain whilst allowing an acceptable light level. The short travel of the operating mechanism and often infrequent need for adjustment ensure that maintenance costs are minimal. More here

Rooflight roller blinds
We do not generally recommend except for small areas (less than 2 sq. m) such as Velux windows. For larger windows or where access is difficult we consider that the risk of high maintenance cost if the material is caught or rolls over could result in an unsatisfactory installation however well made and fitted. Our recommendation is non-retractable blinds. The only exception is in photographic studios where striping from light penetration around the louvres would affect the photography. That is the only situation that we would propose larger rooflight roller blinds.

Conservatory roof roller blinds
Externally the guided and tensioned VZ500 More here is far more effective in reducing solar gain than an internal blind. The system cannot be fitted internally and has not been adapted for this as the sections are large and achieving the tension would not be possible in many internal conditions

Pleated blinds
We consider this to be a domestic solution unsuited to contract applications. The blind is hand drawn on support cables. Only suited to small windows

Roman Blinds
Also mainly a domestic solution. Strips of bamboo are sewn together with a cotton thread into a woven wood known as Pinoleum to form a Roman or Roller type blind. Due to the thickness and weight of the material it is normally only suited to short drops on a roller blind. When used in a rooflight it is supported on steel cables to minimise the sagging. The limitations are that the cotton thread can break down after a time especially if frequently used in a rooflight. In this situation the material is best fixed into a draped effect that is particularly suited to restaurants where the need is for effect and light without glare rather than a moveable system. They create a soft diffused light with the natural beauty of wood.

Question 12

Sealed Glass Blinds - What are the design limitations ?

Accepted Answer

These blinds are assembled with the double glazed units and the spacer bars of the units are also the rail sections enclosing the mechanisms of the blind. The benefits are that they are much less prone to user damage and, as a mid pane blind, are much more effective in rejecting solar gain than a room mounted blind.

However, they should be specified with caution. In our experience the effects on components of the high temperatures generated in a mid pane situation can cause breakdown sooner than for one fitted in the room.

For this reason our industry brand leader limited their system to tilt only with the minimum of mechanisms. All components are metal with special paint finishes and the only nylon components the cord and ladderbraid are woven to allow for shrinkage. That product has been withdrawn from the market.

There are now systems available from the glazing industry that are based on standard blinds with a raise/lower function with nylon components and standard paint finishes. Apart from the effect of fogging of the glass from breakdown of the nylon and paint the chances of them functioning for the duration of the life of the unit is unlikely. Ah you say but they are warranted - read the terms- could you afford the costs involved in replacement of the unit?

The warranty is for the components that can be accessed from outside of the unit. If the motor or any components fails it is simply not cost effective to remove the glass unit to the factory, breaking the seal replacing the blind re-gassing and sealing and returning it to site and meanwhile the window would be boarded up. So it is the cost of replacing the complete unit. Even then the new blind will not have faded so will look different to adjacent units.

On a ten year declining warranty the cost of removing the glass to repair a blind on say the fifth floor of a building, craneage, closing the street etc. needs to be considered. In the ninth year a 10% contribution to the cost of the replacement part of the blind will be a miniscule part of the cost. After the warranty expires how many building users expect to replace the glass on a 10 year cycle for that will be when breakdown will start to occur?

Hence our suggestion of caution, if access for removal is simple, say for internal screens or doors where there is no possibility of solar degradation then they may be appropriate. We have expertise of the technology as we supplied 1022 custom units to the Inland Revenue building in Nottingham in 1994.

They were fitted to the upper part of an arched window the louvres were fixed at an angle of 43° to be a light shelf – no mechanism so not a problem. In situations where removal will be a problem the mid pane blind option would be safer.

Question 13

Sloping Glazing - What are the options ?

Accepted Answer

It depends on what you need the blind for. If it is to reduce solar gain then an external blind may be necessary. The reasons are detailed in what are the requirements for shading a conservatory roof or sloping glazing?

If your requirements are for glare, light control or privacy an internal system will be the most suitable.

Non-retractable Louvre Blinds
Techtonic or Tetrix systems will tilt only to adjust light levels and control glare. Both systems can be mounted externally where they are most effective in reducing solar gain. For most uses an angle will be found that balances the need for glare and heat gain whilst allowing an acceptable light level. The short travel of the operating mechanism and often infrequent need for adjustment ensure that maintenance costs are minimal. More here

Rooflight roller blinds
We do not generally recommend except for small areas (less than 2 sq. m) such as velux windows. For larger windows or where access is difficult we consider that the risk of high maintenance cost if the material is caught or rolls over could result in an unsatisfactory installation however well made and fitted. Our recommendation is non-retractable blinds. The only exception is in photographic studios where striping from light penetration around the louvres would affect the photography. That is the only situation that we would propose larger rooflight roller blinds.

Conservatory roof roller blinds
Externally the guided and tensioned VZ500, more here is far more effective in reducing solar gain than an internal blind. The system cannot be fitted internally and has not been adapted for this as the sections are large and achieving the tension would not be possible in many internal conditions.

Pleated blinds
We consider this to be a domestic solution unsuited to contract applications. The blind is hand drawn on support cables. Only suited to small windows.

Roman Blinds
Also mainly a domestic solution. Strips of bamboo are sewn together with a cotton thread into a woven wood known as pinoleum to form a roman or roller type blind. Due to the thickness and weight of the material it is normally only suited to short drops on a roller blind. When used in a rooflight it is supported on steel cables to minimise the sagging.

The limitations are that the cotton thread can break down after a time especially if frequently used in a rooflight. In this situation the material is best fixed into a draped effect that is particularly suited to restaurants where the need is for effect and light without glare rather than a moveable system. They create a soft diffused light with the natural beauty of wood.

Question 14

Sloping head windows - What are the shading options ?

Accepted Answer

Horizontal Mini blinds
The most practical type of blind for sloping head windows is a horizontal mini Venetian type. Techform mini blinds are available in a wide range of aluminium and timber slats. This range uses conventional Venetian blind design headrails and operating mechanisms and are retractable as far as the shape allows. They hang in the window in the same way as a conventional blind does.

Non-Retractable Blinds
For large windows non-retractable louvre blinds are more practical. They have an aluminium framework that extends at intervals down the length of the blind and is thus is tilt only and non-retractable. It is the most robust option for shaped windows and sloping glazing. More here

Vertical louvre blinds
able for shallow slopes and where there is space at the side for the louvres to stack (ie no cill). Where there is a cill only tilt operation is possible.

Pleated blinds
We consider this to be a domestic solution unsuited to contract applications. The blind is fitted on the cill and is hand drawn up on support cables. Only suited to small windows.

Question 15

Sports Halls - What problems & solutions are there ?

Accepted Answer

Rooflights are a good source of natural light that due to their height are less prone to damage than vertical glazing.

Techtonic non-retractable blinds are the ideal solution to control glare for players and spectators. They are robust, require little maintenance and are easily adjustable. More here

The only problem is that no matter how high the glazing is from floor level a stray ball will inevitably find its way up to it.

T50 flexible slat will not be damaged but could be dislodged from its clips and need re-fitting.

T80 solid slat will flex to light knocks but could be damaged.

T88 extruded slat will withstand heavy knocks.

Re-clipping slats at high level will be either expensive or, even if they have access equipment, will be too much of an inconvenience to staff. Whilst T88 is the best solution it is also considerably more expensive than T50. A better and more cost effective option would be to allow for fitting netting under the area of the blinds to prevent the problem from occurring.

Roller or pleated blinds are not recommended for this application.

Question 16

Swimming pools - What are the special shading requirements?

Accepted Answer

Full height glazing to create a light airy environment can cause a problem with glare on water. Its effect on a rippled surface makes it almost impossible for the lifeguard to see a swimmer in difficulty. Shading is thus essential to eliminate this effect.

Because of the atmosphere blinds should ideally be external. If internal they should be roller blinds with an external grade fabric pvc coated fibreglass mesh material or solid acrylic awning fabric (as they are more resistant to the atmosphere than internal fabrics).

Ideally manual operation should be with a sealed gearbox and cranked detachable operating rod rather than cord.

Question 17

Triangular Windows - What are the shading options?

Accepted Answer

Horizontal Mini blinds
The most practical type of blind for sloping head windows is a horizontal mini venetian type. Techform mini blinds are available in a wide range of aluminium and timber slats. This range uses conventional Venetian blind design headrails and operating mechanisms, retracting as far as the shape allows. They hang in the window in the same way as a conventional blind does.

Non-Retractable Blinds
For large windows Techtonic non-retractable louvre blinds are more practical. They have an aluminium framework that extends at intervals down the length of the blind, therefore is tilt only and non-retractable. It is the most robust option for shaped windows and sloping glazing. More here

Vertical louvre blinds
Suitable for shallow slopes and where there is space at the side for the louvres to stack (i.e. no cill). Where there is a cill only tilt operation is possible.

Pleated blinds
We consider this to be a domestic solution unsuited to contract applications. The blind is fitted on the cill and is hand drawn up on support cables. Only suited to small windows

Roller blinds
The roller would be mounted at the cill. The centre of the fabric needs to be reinforced to allow a centre draw. This causes strain on a small area of the cloth and inadequate support at the sides which will sag. This is not an option that we would recommend.

Question 18

Roller blinds - Can they be made to draw up?

Accepted Answer

Fitting blinds at the cill is sometimes necessary if there is insufficient clearance at the head to fit the roller. It is also a means of providing privacy in the lower part of the window whilst still allowing light from the top.

To be most effective blind draws up with an all round rather than a centre pull to pulleys at the top and the cords are tied off to a cleat on the wall. These controls can only be used in commercial areas assessed as not having a child safety risk as there are slack cords when the blind is retracted. For domestic properties the only option is a centre pull tab to a hook or turn button at a point on the window frame cross bars that can be reached.

We recommend that upward draw should only be chosen if there is not an alternative as the roll of the cloth will collect dust and, apart from leaving unsightly marks, it could cause the cloth to run off square.

Question 19

Roller blinds - Can they be made up in my own fabric?

Accepted Answer

Fabric for a roller blind must be dimensionally stable otherwise it will not roll up evenly. To test if it is suitable if you hold both sides of the piece of material the weave will not move out of line if you move your hands in opposite directions.

If it is not suitable it is necessary to stiffen the cloth by laminating a backing fabric to it. There are also aerosol sprays that apply a stiffening coating but they tend to be less successful. Laminating is a specialist process available from Lonsdale Window Fashions.

Question 20

Roller blinds - How wide can they be made?

Accepted Answer

It is technically possible to make one up to 6.5 metres wide, as we do for awnings, but that answer needs to be taken with caution as drop size and fabric weight then become a consideration.

The size and structure of the roller and type of operation will determine size, as well as, width, fabric weight and drop. Standard rollers are 25, 32 and 45mm and for most fabrics a 45mm tube will be adequate up to 3m wide or 8 sq. m and can be spring or gear operated.

Beyond that a 60mm tube with a gearbox or electric operation will be suitable up to 4.5m wide or 12 sq m but it does need to be a very stable fabric. At sizes over this width the roller will have a tendency to deflect and cause puckering (known as herringboning) and there can also be uneven roll of the cloth especially if there is a cross seam.

So over 4.5m the largest standard roller tube would be 78mm and to avoid a cross seam the maximum drop should not exceed cloth roll width less 300mm ie. 3m cloth width = maximum drop 2700. The herringboning problem does not occur with awnings where the system keeps the cloth under tension rather than relying on the gravity weight of the bottom rail. More here

For blinds over 5m width we have a special reinforced roller tube of 150mm diameter that will span up to 6.5 metres with a deflection of less than 5mm for an average weight cloth so long drops are also possible. At this size operation is always motorised.

Question 21

Wood Blinds - Does the timber come from renewable resources?

Accepted Answer

Basswood used in Hallmark's blinds is certified as coming from well managed forests adhering to strict environment and Socio Economic standards set out by the Forest Stewardship Council www.fsc.org
Initiated in 1989, Smartwood is the oldest and most extensive certification programme in the world. Smartwood is a programme of the Rainforest Alliance. Though the programme originally focused on tropical forests, today Smartwood now works in all forest types – tropical, temperate and boreal – and operations, including natural forests, plantations, large scale operations and small scale community projects.

Through certification and use of the Smartwood label, the programme provides a commercial incentive for forest managers to adopt sustainable forestry practices. Smartwood certifies forest products that come from “well managed” forests (“sources”). This ensures that timber harvesting is ecologically sound and both socially and economically beneficial to local communities.

Question 22

British Standards: What standards are there for blinds?

Accepted Answer

The few British Standards relating to blinds and shutters have now been virtually replaced by EU standards that have been developed over the last 30 years. Our trade association (BBSA) was involved from the outset and the UK was one of the lead nations in the process. They are now BS.EN standards and the UK continues to be involved in developing EU and International (ISO) standards.

The objective was to produce standards that were realistically achievable and that would provide a measure of quality to the end user without imposing unnecessary cost and bureaucracy on manufacturers.

All standards relating to blinds and shutters can be self-certifying, that is the manufacturer certifies that the product will meet the standard required. Most European manufactured product will reach the minimum performance levels. The purpose of the standards is not to involve manufacturers in extensive testing when results in use can confirm performance.

However, where there are Health and Safety issues there are some mandated requirements. These are issues such as child safe looped cords for internal blinds, wind loading on awnings and safety devices on motorised shutters. To claim a standard the manufacturer must be able to show that he has tested to the mandated requirements.

Standards include a requirement for installation instructions and for the standard to be valid the blind or shutter must be installed in accordance with those instructions.

So we suggest that if you are specifying or ordering product you would expect the manufacturer to be able to confirm the test level of any mandated requirements and you should specify that it should be installed in accordance with them. For other standards you may wish to expect the manufacturer to confirm that the product is capable of meeting any relevant standards.

There are also requirements for recommendations from product maintenance and most warranties will be conditional upon these being adhered to.

A list of Standards can be found on this document

Question 23

Flameproof and fireproof what is the difference?

Accepted Answer

Fireproof will not burn and there is very little that will meet that definition. It is applied to fire sensitive sites such as oil rigs.

Flameproof or Flame retardant are the terms normally applied to sunscreening. They mean that the blind will not be the source of a fire. So the test is that if a flame is applied to the product for a period of time it will not ignite or it will self extinguish. There are various UK, French and German standards which, if agreement can be reached, will eventually be replaced by EU standards including our own BS5687. *
For example a wooden Venetian blind is flame retardant. Try putting a flame to a 3mm piece of wood and see how long it takes to catch alight.

So the standard seeks to stop the blind being the source of a fire it does not mean that it will not burn. Most fabrics and materials are not inherently flameproof so require a flame retardant treatment to meet the standards.

In fact when they do burn most flame retardant treatments give off toxic fumes that are more life threatening than the fire itself. But at least you will know that as the treatment chokes you to death the blind did not start the fire!

There are not any specific regulations on the use of FR materials in commercial and domestic premises except for public places where the Fire Officer may expect blinds to meet a standard for furnishings.

Other than a cigarette in an ashtray on the cill what is likely to cause the fabric of a blind to ignite? If the answer is that the possibility is so remote that it is not identifiable then surely the greater risk would be from toxic smoke inhalation where the fire source is elsewhere in the building. Now that smoking is banned in commercial premises it does pose the question as to what is the risk that could cause the shading to be the source of a fire.

Many domestic fires occur from refraction of the suns ray’s from mirrors or reflective materials on the window cill. Any flame retardant product would not be a barrier to fire spread from that intense source – keep window cills clear.

Where FR treatment should be considered:
Domestic or Residential properties where smoking is permitted
Areas where it is not permitted that smokers might still use
School laboratories where sparks could occur from experiments
Domestic or Commercial premises where candles are used
A window area adjacent to a coal fire where sparks could be emitted
* “These have not been finalised, at this stage there is not a suitable test method or equipment to test to an agreed common standard. As at May 2007 the BBSA/BSI committee agreed that British Standard BS5687 would be retained for the foreseeable future and this is still the position.

Question 24

What where the earliest types of Venetian blind?

Accepted Answer

The History of Venetian Blinds
Venetian blinds were the earliest type of sunblind and their history can be traced back to around 4000BC in Persepolis in Persia. Then perforated clay tiles were used to cover window openings. In most European languages this slatted type of shutter blind is still known as the Persienne blind from these early origins. This was later incorrectly translated into English as the Venetian Blind. Later Persienne also described a style of shutter blind that was made from alabaster and marble and found in Minoic Crete.

By Roman times glass began to replace shutters and this decline continued into the middle ages, when fear of light caused windows to become exceedingly small. By the 16th century window sizes had increased but were usually covered with parchment or oiled linen cloth. This later developed into the Scotch Holland roller blind of the 19th and early 20th centuries to become the spring roller blind of today.

“French Windows” that were introduced during the French renaissance incorporated the first wood sunshades. At first these were like wooden shutters and evolved in time into Venetian blinds that were able to be raised and then tilted. The timber slatted Venetian blind became very popular in the late 19th and early 20th centuries until in the 1940’s the introduction of aluminium started to replace the wooden slats. The early aluminium blind still retained the timber rail sections, cast metal fittings and wide cotton tapes of the timber blind.

By the late 1940's and early 1950's pressed steel fittings and mass production techniques had been introduced. The development of plastic in the 60’s led to the use of nylon components which significantly reduced the size of the rail sections. Automated machinery for manufacture was developed which now forms the slat, punches it and threads it between the ladderbraid. Even timber blinds are now fabricated on automatic machines considerably reducing manufacturing times and thus the cost of the finished blind.

Question 25

What are the origins of Roller Blinds?

Accepted Answer

The Scotch Holland roller blind has a history dating back as far as the early part of the 18th Century. The earliest material used for the purpose of making roller blinds seems to have been Holland linen cloth, which as the name implies, originally came from, or at least, was bleached in Holland and laid out to dry in the fields. Picture if you can, some Dutchman in a theatre in Amsterdam, looking idly at the linen stage curtain as it rose and fell, when suddenly, the idea of a window blind made from Holland cloth struck him. Shouting the Dutch word for “Eureka!” he would jump madly from the fauteuil to rush home to sketch the first drawings from which the blind was to be made. Little would he think that his invention would cast it’s shade over the whole world – if you would excuse the pun.

Actual records of the manufacture of Scotch Holland fabric go back to Glasgow 1725, to a weaver of white linen cloth for blinds, James Louis Robertson. Apparently, in 1773, he updated his production of the cloth by installing two new looms which were powered by a large Newfoundland dog performing the role of a gin horse within a large tread wheel. In 1775, a few miles down the road, John King opened a weaving factory to produce a similar cloth. The original wooden roller blind had no spring and was developed from the old “bookfold” system where the cloth lay in folds like a concertina on the window cill and was raised to cover the window by a cord attached to a “top rod”.

The cord was then secured to a cleat to prevent it dropping back. This system prevailed for many years until someone invented a roller with a flange end, but this still had to be secured to a cleat. It is not known when the modern spring roller was invented, except that it was well into the 19th century, but it is known that it was very slow to become popular as people did not trust the new fangled springs.

The earliest manufacturers of Scotch Holland cloth still chose to use the heavy duty Dutch linen, which was then bleached, dyed and heavily starched. Whilst still wet the cloth was layered between two sheets of brown paper and then wound around great drying cylinders above which were suspended heavy beating bars of solid wood. These bars measured 4-5 inches square and were 12 foot long.

The beaters were rounded at the ends to strike the cloth without damage and were commonly known by the workers as “beetles”. The beetle gantry consisted of a row of 30-40 of the wooden bars and an enormous power driven cam-shaft revolving alongside. Each beetle had a lug which caught on the cam and was thus lifted some 12-18 inches, after which it slipped off and was allowed to free fall onto the rotating cloth on the large cylinder beneath. This process was repetitive and the beetles would be raised and dropped in quick succession, continuing for 3-4 days. The beating process made the fibres of the cloth spread and gave the cloth a “polished” look to the surface of the fabric – the interleaved brown paper successfully polishing the underside layers.

After a few days the fabric was unwound, re-wetted and reverse mounted on to the drying drums to be given another 3-4 days of pounding. The beetling shed, as it was known, was an unenviable place to work and, as you may imagine, the thunderous noise produced, shook the ground around, and, in the early days before ear protection, resulted in many of the workers becoming stone deaf. Later on during the second world war flashing lights had to be installed instead of sirens so that workers could be warned of impending air raids.
In this way the unique qualities of the Scotch Holland fabric were achieved, a cloth that is renowned for its finish and durability.

The whole process took about 10 days and the widest fabric produced was 112 inches. The name “Scotch Holland” was coined because, like scotch whisky, pure Scottish spring water was required to impart that unique property to the cloth and although many attempts were made to reproduce it in other parts of the world – just like whisky – it proved impossible.

To complete a Scotch Holland roller blind, the famous fabric was cut to size and secured with small tacks to a one piece round wooden batten. The bottom of the blind had a pocket in the fabric to take a wooden bottom bar and all the side hems were hand sewn using a herringbone stitch to prevent fraying. Glace cords were used to operate the blind. Brass pins were inserted into the end of the roller and the blind was located into small brass flanges which effectively made the fixing brackets.

The developments of alternatives for the mass market and the high cost of production by traditional methods led to a decline in demand and production of Holland fabric was discontinued in Scotland in the early 1980’s

The Hallmark traditional roller blind uses the best available quality cotton material to replicate as closely as possible to the original. The finish fittings and production methods are the same, producing a blind to the quality standards of yesteryear.

Question 26

What are the origins of traditional Awnings?

Accepted Answer

Traditional steel framed shop blinds will last for decades many that you will still see in use are well over half a century old. The cloth will have been changed but the mechanism and the nameplate of the maker from bygone times still survive. The mechanisms are generally much stronger than the most robust aluminium blind and are the nearest to an all weather blind that a shop keeper can expect. They date from the times when every blindmaker had a blacksmiths shop and the fitter adjusted the steel arms by bending them in the nearest drain cover!

The Trellis arm awning over the entrance to our office dates from a least as far back as the 1930’s when we believe the building was extended and it still has the cloth that was last changed in 1992.

Before the days of refrigeration shopkeepers knew the importance of shop awnings to shade the window and preserve their wares so every shop had its cotton duck canvas awning. The blind box was usually fitted above the name board as the earliest types of frames were simple drop arms. That meant that to get a projection that would give cover to the glass, usually 7 feet (2.13m) and to allow head clearance under the front rail the roller had to be fitted 14ft above the floor level.

At that height the awning covered the nameboard so to identify the type of shop each trade often had its own colours and the traders name was sign written on to the fabric. The butchers shop was recognisable from the red and white stripes the fishmonger was blue and white and the greengrocer green and white.
Nowadays aluminium has replaced the steel framework of awnings as it is easier to fabricate and less expensive than steel. Traditional cotton duck canvas has been replaced by modern acrylic fabric. It has the same look but as it has significant benefits in chemical and weather resistance and has effectively replaced cotton even on traditional sites.

We can still produce most of the traditional types although the cost is significantly higher than the aluminium equivalent.

Question 27

Home Management Systems How do I link to my blind controls?

Accepted Answer

Most systems are now able to provide the correct signals for operation of blinds but if you are not using a custom automated control system for shading you should check with the supplier on the following points.

1. The essential difference with say lighting controls that require an on/off shading requires a stop function that is up/stop/down. The stop facility is essential. Reversing the signal lines is not an option a separate common is necessary i.e. you cannot use the closed as the common on the open signal.

2. The system should also allow that because switching is instant a millisecond time delay should be allowed to avoid the motor receiving simultaneous up and down signals that could override the limits.

3. If the option is to link the system with our systems it may not be possible without an interface box

4. If it is possible the signal lines from the home automation system are connected to the bus line of our interface box, a volt free contact is required. The stop is achieved by a simultaneous impulse signal across both open and closed contacts.  Open and closed for non-retractable blinds or louvres would be up and down for Venetian or roller blinds.

As the receiver can be programmed to receive instructions from more than one transmitter the blinds can be operated from the home automation console or there is the option to use a separate hand held or wall mounted transmitter.

The blind motor is located in the motor tube or blind headrail and a connector plug or junction box is required adjacent to the blind so that it can easily be disconnected from the power.

If using a receiver box it is normally located near to the motor to reduce the cable runs from the motor.
As the system is radio remote the transmitter does not have to be in line of sight and will pass through walls although the distance should not be more than 200 metres in open space reducing to 20 metres through 2 concrete walls.

Question 28

Radio remote or hard wired - which should I choose?

Accepted Answer

Where possible we would always recommend hard wired for a commercial installation. For domestic controls radio remote (RTS) can be more convenient for the user.

Hard wired rather than RTS
Staff changes at commercial installations could result in knowledge of need to replace radio remote batteries being lost.
Where radio remote wall switches are used it may not be remembered that they are battery operated and that they need changing every 2-3 years.
Hand held transmitters could be misplaced.
Fault tracing is easier

RTS rather than hard wired
Can link to Wifi controls to enable remote operation and can link with other building controls.

Reduces need for wiring runs.

Attractive handsets are more convenient for the user.
Where decorations would be disturbed it eliminates the need for chasing out to the switch point thus avoiding damage.

Can avoid need for relays that are required when hard wired blinds operate in a group on a control system.
Solves a problem caused when the contractor allows only a fused spur to operate blinds without including a switch line.

Radio Remote Control should not be used in areas near embassies as they are exempt from radio interference legislation. That has been responsible for complete systems being inoperable with the cost of replacement for a hard wired system.

Question 29

Wiring diagrams

Accepted Answer

The basic connection diagram for a 240V single motor and switch can be accessed below. Link Diagrams for control systems or multiple motor installations are available. We have not included on this site as we believe that it is necessary to check your requirements to ensure that you have the correct one

Question 30

Blind Boxing what do I need to allow for roller, Venetian and shop blinds?

Accepted Answer

Internal blinds
The size is more dependant on the ability of the installer to fit the blind into the brackets than the size of the build up of the cloth or louvres.

Timber grounds should be provided before the recess is created for ease of fixing of the brackets.

For a roller blind the size depends on the roller size, build up of cloth and clearance.

As a guide for blinds up to 1.5m in width and drop allow a minimum of 70mm square, up to 2m in width and drop 90mm and 3m in width and drop 120mm. The exact minimum size will depend on the type of cloth so if it needs to be smaller than these guide sizes check with us.

If it is to retract into a slot with a cover board the board has to be removable for access and the edge of the board has to be smooth as the cloth could rub against it as the roll reduces. The bottom bar should not be designed to retract into the box. Our Hemera 120 roller blind has a box with a lower access plate. More here

For Venetian blinds the depth of the recess depends on the drop of the blind. This is shown on the product data sheets. More here

External blinds
The size of the opening should allow for access but should not be too wide to enable birds to penetrate and nest. Maintenance men removing fledglings can be disturbing to occupants!

Creating the recess in the building design can significantly reduce the cost and make the installation less obtrusive when retracted. Suitable fixing grounds should be provided at the bracket fixing positions.

The depth of the box for external Venetian blinds depends on the blind drop and is shown on the Trojan data sheets. link

If the drop is to floor level check with our technical department that it will be possible to fit the guides into the box.

It is possible for our Hemera external roller blinds to be recessed into the building but it is necessary to check your proposals with our technical dept. to ensure that fixing positions are adequate, that the operation is not impeded and that access for maintenance is feasible.

Where it is required to recess side guides that means that the blind will be wider than the created opening. The design has to allow for access to fit and remove the blind for maintenance.

Most awnings are designed for face mounting only and will not close back into a recess box

Shop Blind Boxing
Sprung roller or electric traditional shop blinds fit into a standard opening. Most aluminium framed folding arm types are not suited to a recessed box as the arms have to lift before entering the box and the front rail has to be of a type that closes to the box.

The bottom and back of the box must be zinc or lead lined to prevent water ingress to the building. The end cheeks to which the brackets will be fitted must be securely fixed in position to the building structure.

Question 31

Automatic control systems what are the options?

Accepted Answer

Automation enables the maximum benefit from energy saving shading strategies. That benefit can only be achieved if the shading is in the correct position required for changing weather conditions and user requirements.

An extensive range of standard control systems is available with custom design for more complex requirements. Control systems can be made to perform virtually any sequence of functions. It is up to the specifier to identify the priorities and choose the one best suited to the job. It is the essential to convey that intent to the user.

Control systems offer the designer uniformity and building temperature control that can make significant savings in air conditioning and thus energy costs.

Our standard range is described in our automatic control systems leaflet, more here.

Question 32

Motorised blinds what are the options and requirements?

Accepted Answer

Almost all types of blinds can be electrically operated. For roller blinds the motor is tubular and fitted within the roller.

For venetian blinds the motor is fitted within the headrail and for vertical blinds on the back of the track. Non-retractable blinds have the motors mounted on one of the racks above the louvers.

Most motors are 240V and larger shutters will be three phase although small blinds can be 12 or 24 low voltage. All motors have adjustable built-in limit switches.

Switches should be of an approved type that is retractive (centres to off) or has a push to off facility.

Motors are supplied with a lead of at least a metre from the end of the blind. It is necessary for this to be connected by the electrician to a junction plug or box so that the blind can be easily removed for maintenance.

Most 240v motors are single phase using normal 1.5mm 3 core mains supply to the switch. The cable to the motor must be 4 core There are wires for supply, one for raise and one for lower, a neutral and earth. The load requirement is normally not more than an amp for each motor. Where more than one blind operates from a single switch relays must be used (to prevent feedback overriding the motor limits). They can also serve as motor cable junction boxes.

Low voltage motors have a 2 core cable from the motor. Long cable runs from the power supply could cause voltage drop so should be avoided. The motors can be linked in series, relays are not required.

Installation
installers and fitters of blinds will not undertake mains wiring as part of their contract as this must be carried out by a qualified electrician. Normally this work is carried out by the site electrician or an electrician familiar with the client’s building. Thus electrical items are supplied only.

The blind fitter is responsible for final testing and commissioning and setting the motor operating limits. Usually the blinds are tested from an independent power source before final connection.

Question 33

Switches: Can the ones for my motorised blinds match my others?

Accepted Answer

Most switches are two way on and off and are not suitable. We need two directions and an off function that can only be achieved with a centre retractive (biased off) switch.

This is so that the blind can be stopped at any height and with a Venetian type to allow adjustment of the tilt. The Wandsworth range includes a centre off rocker switch, Series 2 No 164PB that is suitable. K4900 is the centre off switch In the MK range.

If the blinds have a control system the switches also need a stop function* and our standard switches must be used. The alternative is to have a system with radio remote senders or for the controls to be linked to a BMS or Home Management System. More here

Some motor manufacturer’s warranties are invalid if their switches or approved switches and controls are not used. Approval should be sought for the type that you propose to use.

*The stop function is achieved with a simultaneous momentary signal across both the raise and lower connections

Question 34

Shop blinds - What are the headroom clearance requirements for the frames?

Accepted Answer

This depends on the regulation of the local authority. Most set a standard of 7’ or 7’ 6” (2130mm or 2280mm). Even at this height all projecting frames (and anything fixed or hung on them) must have rounded edges,

Question 35

Shop blinds - What are the clearance requirements from the front of the blind to the curb?

Accepted Answer

This depends on the local authority. Apart from local regulations premises on corners or on narrow streets should consider the effect of vehicles mounting the pavement.

Also the local authority will not appreciate their street furniture (signage) being blocked by a sunblind.

Question 36

Shop blinds - If I have side curtains on my shop blind can I have a stall behind them?

Accepted Answer

Side curtains are designed to protect the window display such as meat in butchers’ shops from the effect of low angle sun. They should not obstruct the pavement and goods must not be stacked behind them.

Question 37

Cleaning and maintenance - what is required?

Accepted Answer

Cleaning
Banning smoking in offices has had a significant effect on the need for cleaning internal blinds. Before that happened nicotine would stick to the blinds (and all other decorations and furnishings) and dust and dirt would adhere to the nicotine.

Our business originally started by cleaning blinds in the late 60’s and early 70’s when office blinds needed to be removed for cleaning on a yearly cycle. In areas where grease in the atmosphere from adjacent restaurants created an even stickier film on the blinds sometimes 6 monthly.

This process also allowed for an annual maintenance check of the cords and mechanisms.
If the blinds now do not look so dirty it does not mean that they do not need cleaning. Whilst we recommend that this should be done on an annual basis. We recognise that when the need is less visible budgets may be restricted but it should not be overlooked. Cleaning should be factored into the budget at least on a 2-3 year cycle and should be allowed for every year.

Maintenance
Certainly, an annual maintenance inspection will be cost effective in that it reduces the possibility of breakdown call outs. That inspection does not require an engineer. Apart from looking for any obvious signs of malfunction wear to the cords or lift tapes will be more obvious toward the bottom of the blind.

Question 38

Bay window or corner - what allowances are required?

Accepted Answer

How do I fit roller blinds at a corner?

The gap between the cloth and brackets is exaggerated at a corner. To minimise it the operation of the rollers can be changed to roll over i.e. the cloth rolls from the front of the roller instead of the back.

This means that the cloths are closer together. If there are adjacent blinds they may have to be rolled in the same way for appearance although light ingress at the sides will be greater as the cloth is further away from the window frame than with normal roll.

Take a template of the corner detail that will allow us to advise on the tolerances required.

Question 39

Roller blinds - how can you guide a sloping blind?

Accepted Answer

All round pull and bridle pull
Where spring roller blinds need to be controlled on sloping glazing or drawn up a centre cord is not suitable as the control needs to be at the edge of the cloth.

Pulleys are used in either a bridle or an all round pull. The latter is best as it balances the pull on both sides and should be used on larger blinds it has a 2:1 reduction so is easier to operate. This means that it has twice as much cord to draw and tie off so, if this is an issue, use the bridle pull.

These solutions may not be suitable in domestic properties or public places where child safety is an issue if the control cords are accessible to young children.

Understanding Part-O