Does the perfect insulation product exist for windows ?

24 Dec

KalaBlinds roller shutters

roller shutters  07411 070 442

0151 324 1159

The roller shutter is almost the perfect solution to the future requirement in the insulation of our homes because of its flexibilty, studies have shown that the addition of roller shutters to a window offers the most flexible solution and will reduce the u-value of the window (from 1,8W/m²K to 0,81W/m²K) and ultimately save the householder money on their fuel bills (Synertech Systems 2007 p7). The overall effect of the shutter will depend on various factors but a figure of 55% is realistic. Local authorities have also expressed an interest in shading the window as viable solution in the desire to improve the home’s efficiency. In monetary terms we could see a 15-24% reduction in annual fuel bill achieved through a reduction in heating requirements and increase in winter solar heat gain plus a reduction in the need for summer cooling. In a mixed climate such as the UK has, the best solution with regard to improving window must be a flexible dynamic solution.

Window value W/m²K (the lower the value, the better Passivhaus 0,8).

Window only

With heavy curtains

With insulated shutters

Single glazed




Double glazed, 12mm cavity




Double glazed, 16mm cavity, Low-E




Triple glazed




Triple glazed, 2 low-E, argon filled







Window + Kalablinds Termicur 45

Double glazed, argon filled, Low-e, en=0,2, hard coat

1,8 W/m²K

0,81 W/m²K


Glass is a commonly used material for windows which I consider to be a compromise material. Its main function is to allow light into the home and this is where the problems begin. The glass itself doesn’t have particularly good insulation properties, but if we sandwich a gas between two pieces of glass it will improve the insulation properties, will it not?

As we improve the insulation qualities we can install bigger windows which will increase the risk of over heating, a problem that can be overcome by adding elements to the glass and ultimately reducing the transfer of light, but it does have an effect in reducing radiated heat losses, which defeats the objective of bigger windows. And even with this double glazing we are only achieving u-values in the region of 1,5W/m²ºC, without having to spend large amounts of money, add a roller shutter and we could have figures closer to 0,8W/m²ºC which should be considered a significant decrease. Further reading.

Demanding further reductions in the heatloss of the property in an attempt for homes to be net zero carbon by 2016 (Communities and Local Government consultation document Road to Zero Carbon 2009) there is an increrasing pressure to both reduce consumption and increasing insulation, perhaps we should look at triple glazing?

If we look at triple glazing we need to be sure that the benefits outweigh the costs and that the glazing units are not so heavy as to render them difficult or uncomfortable to use.

If we now think that glass has reached the limit of its performance without dramatically increasing costs for very little return.

Was solar heat gain (p16) mentioned and the increased usage and perceived need for air conditioning? If air conditioning is seen as the solution to over heating, what are the solutions to offset this increase in the consumption of energy?

While glass serves a purpose, it is limited in use and requires, in my opinion, a product to complement it to help us get a better performance from our windows.

How can we do this?

Orientation, this is a permanent fix as it is the design of the building and relates to the size and positioning of the windows and that is not a realistic option as the property will either suffer from significant heat gain or significant heat loss or both, or not receive enough sunlight.

Awnings, these allow the windows to be protected from the solar heat gain but don’t provide any protection against heat loss through the glass and are an external fit affecting the aesthetic of the building and possibly have legal consequences if opening onto the public highway and not a particularly good option during windy conditions. It is, however, probably the cheapest alternative.

Overhangs can be designed into the structure to protect the home from the summer sun while allowing the lower, winter sun to passively warm the property up, easing pressure on the heating system. Like the awning there is not protection against heat loss.

Louvres, either external or internal. External louvres will prevent solar heat gain overheating the building but won’t protect against heat loss while being a permanent fixture that obscures the view. Internal louvres while protecting against heat loss through the glass do not offer the best solution against solar heat gain.

Roller Shutters offer the flexibility to be used when necessary. Thay can be used in the summer to protect against solar heat gain (g-value 0,05-0,1) while still allowing enough light into the building to negate the need for daytime lighting or air conditioning. The boxes can be mounted internally having a minimum impact on the look of the building being supplied in a variety of colours that can equally have a large impact of the building. During the winter months the shutters can be dropped during the long hours of darkness to prevent night time heatloss benefitting from the insulating characteristics.

(more info).

The mechanically operated, DIY units are both trouble free and easy to maintain and operate. (motorised units are available).

An added and previously unmentioned benefit is one of security that is sure to put off the opportunistic burglar and as the total cost of an individual burglary is put at over £3,000 (Home Office figures) we can begin to see clear benefits. We are taking something currently provided by glass and improving it, so rather than being competition to glass the roller shutter is an addition and in the long term a sensible proven solution in the challenge of reducing thermal losses in the home and reducing solar heat gains.


As the building regs 2010 edition are focussing on solar heat gain as a potential problem, futureproofing from now should be a major considerations.

As the owner of a private new residential build, you can design into your home with your architect the roller shutters and futureproof your windows and benefit from something that will not only prove effective in reducing the energy bill but will also add to the aesthetics.

As a provider of sheltered homes you are in a position to provide your customers with the best products and services available and demonstrate your position as leaders in the world of construction. Roller shutters can be a useful addition to any property helping to reduce energy usage and providing an element of security without affecting the look of the building negatively.

As a distributor I am in a position to negotiate the best deals for the customer and my experience of foreign markets allows me to find the best products and most reliable suppliers resulting in better prices and levels of service for you. You will be working with a company that prides it self on delivering when it says it will deliver, allowing you to plan your time without any extra worry.

Close ties with logistic companies will allow us to deliver to site on an agreed date.

I have worked within either a sales environment or closely with the construction industry both in the UK and Spain for the last 25 years developing various skills and networks. This has resulted in a new venture that I hope to develop and help in the way we live our lives and express ourselves through our homes, while saving money and reducing carbon emissions.

In conclusion, the roller shutter is a solution that complements and advances current levels of insulation and protection without detracting from the aesthetic properties.

They are a long term cost effective solution that will future proof our homes in the battle to improve effiencies in the home.

They are simple to install, use and maintain providing a win/win/win solution.

I would very much welcome your opinions with regards to the advantages or disadvantages of the various systems available.


Four weeks to lose the illegal shutters.

7 Aug

A BOSTON shopkeeper has been refused an appeal for more time to remove roller shutter doors after installing them without planning permission.

Fortunately there are solutions to the less than elegant galvanised shutter mounted on the exterior. Aluminium slats that can be coloured to a RAL colour of your choice. Built in head boxes that keep the façade nice and clean or even fully internally mounted shutter that provide the security you need.ImageSlats with cut outs that keep all your stock on display and secure.
Anti lift design means that the shutter cannot be lifted providing the ultimate in shutter security.

Building Regulations: Part L Changes Explained

5 Aug

Supplementary Issues

Lighting, ventilation, solar heat gain and possible overheating will all impact on the potential to hit the 25% reduction target but until now have not really troubled us. The new regulations give these issues more emphasis and their energy consumption now forms part of the SAP calculation. The need now exists to consider these issues at the design stage, deal with them properly and account for their impact.

– See more at:

Which is, of course, an important step forward, especially for anyone who’s been suffering in the recent heatwave. And as we all know installation at design stage is by far the most economical method. When the shutter can offer a reduction of heatloss through the window of around 55% (SAP) and reduce solar heat gain and improve security and ventialtion, it becomes an important factor to the future of the design of homes.
The cost of retrofitting is simply an economy of scale, but needn’t be overly expensive if the product is selected carefully.

Facebook page.

30 Jul

Slowly catching up to the modern speed of things and as a certain Mr May might say, time for a FaceTube page and another opportunity to showcase shutters, look at some beautiful buildings and chat. is here.


10 ways the UK is ill-prepared for a heatwave (BBC)

18 Jul

1. The design of modern flats

The average UK one-bedroom home is a compact 46 sq m (495 sq ft), according to the Royal Institute of British Architects. And as well as being on the small side it’s also increasingly very insulated. [More….]


When the preoccupation is insulation and keeping heat in, there are always going to be problems during a heatwave. In a country that doesn’t receive much light, we need larger windows. When these windows are designed to maximise solar heat gain in the winter we need to remember that they are also maximising solar heat gain in the summer, add this to the high level of insulation in order to trap the heat we can begin to see a problem developing. The result of this is not looking good as there is a view that there is likely to be an increase in the levels of heat related deaths.

Air conditioning units are celebrating a huge increase in sales, good for the economy, good for the producers, good for the energy suppliers. But aren’t we attempting to reduce energy consumption?

Poorly designed buildings that are too focussed on retaining heat while ignoring climate change. I remember the heatwave of 1976, the next in 2003, then 2006 and now 2013. Recognising and accepting future climate changes is quite subjective. Is the weather becoming more extreme? Is it just a blip in a bigger cycle?

I agree in that homes must be insulated to high levels in order to reduce energy consumption, to this end I am somewhat confused as to why our windows are not receiving the same level of attention. Low-e coatings are wonderful and a much needed improvement over glass of old, but it does have a nasty habit of keeping the heat in in the summer too.

Of course, there is a question of cost and payback periods in regard to adding to the building process. So, to this end, we need to look at the costs and how this affects the overall build cost. The built in roller shutters is installed at the same time as the window, it arrives on site in a pre-assembled state and will add a minimal cost. what is more important to think about is the savings that can be made in other areas. By reducing the window u-value from 1,8w/m²k to 0,81w/m²k, we already have a significant saving- we can have a well insulated window unit without resorting to triple glazing. The cooling and improved ventialtion removes the need for mechanical cooling and ventilation equipment. The nature of shutter design will reduce maintenance costs that accumulate over the life of a building. The fact that a burglary has an average cost of around £3.000, the prevention of this cost is important.

If the cost of shutters for a typical house, if such a thing exists….  is £2.000 +VAT and an anual reduction in the heating bill is 10%, removing the need to buy a couple of £500 air conditioning units and their associated running cost added to the 5-10% reduction in home insurance costs and the likelyhood of not incurring the financial or emotional costs of burglary. We can see that the payback period is very short.

If we can prevent the heat from entering the building in the first place, half the battle is won.

Typical homes and shutter costs.

15 Jul

The cost of roller shutters.

Roller shutters can help you reduce both the heating and cooling load and the related costs. But like all things we are more concerned with the financial savings and payback periods rather than reducing emmissions.

But here goes.

A recent survey showed that heatloss through the window can be as much as 30% of total heatloss and that shutters can reduce heatloss by 55%, that’ll be 16,5% off the heating bill.

Shutters will also aid cooling and ventilation, as we saw in 2003, there was a spike in air conditioning sales as people looked to solve the problem of overheating homes. How much does the air con cost to buy and run? Is the addition of a heat pump really the solution?

Why not stop the home heating up in the first place? Why not look at countries that more experience of dealing with heat than us? Let’s look at Southern Europe or Australia, for example, and their usage of shutters in order to keep cool..

How much will it cost me to buy the shutters? Below are some tables of typical window sizes based on a Which? Article and only serve as a guide.


All prices exclude VAT, but do include delivery and are based on supply only as part of a complete package for whole house.


Where should the low-e coating be installed?

14 Jul

To be most effective in climates where you want to block heat loss but allow beneficial solar gain to enter, the low-e coating should be located on the outer surface of the inner pane of glass–in the window industry, this is known as the #3 surface (in denoting surfaces, you always start with the outermost surface). In warmer climates where you’re more concerned with keeping unwanted heat out, the preferred location for the low-e coating is the #2 surface (the inner face of the outer pane of glass). I remember seeing a German window one time with a sash designed to be flipped seasonally to optimize the low-e coating location (those Germans!), illustrating that point.


I feel that the German solution illustrates the weakness of low e solutions. The glass and coatings can only ever do one specific job, and in a climate that that suffers from a range of conditions and temperatures we have to choose the job we want it to do. As the Germans have discovered, the solution is dynamic. Even a quick walk around town during the current glorious weather shows the downfall. UK windows are sold, or bought, with the focus on the #3 surface and heat retention. At the moment all I see are drawn curtains and open windows. Neither are particularly good solutions, but would appear to be what the public are demanding- shading with ventilation.


Self build & design Manchester

7 Jul

With enthusiasm I woke up at 6am this morning, a Sunday and my birthday with the view of enjoying a wonderful exhibition day in Manchester Central.

My first impession on arrival was that I’d got the date wrong, the big hall was all closed up and I couldn’t see any signage until the last minute. I nearly went home. I wasn’t put off by the lack of queues or throngs of people, it was 10am on a Sunday afterall.

Into the hall, and wow! This intimate and friendly venue was, I don’t know, was, empty. I thought again that I’d made a mistake, but no.

In to the breach…

I do enjoy exhibitions as they are a great way of meeting people and talking in a less formal environment and I have made some excellent contacts and picked up some quality information. I would also like to think that I’ve been able to have a positive effect on the people I’ve met. Exhibitions are always educational, I now know that a pizza oven from Logs Direct Ltd can be used as a source of heat on the patio rather than just for cooking the food of gods.

More interesting, for me, was the conversations I had with a couple of architects and it made me aware of how little information there is out there regarding shutters. At one point I was told that a pair of curtains will do as good a job as shutters. This was a young guy who I’d have thought wasn’t long out of uni and at the cutting edge of technology. It’s funny how opinions can differ as his second thought was that shutters would have more of a place on office buildings rather than residential. I disagree on an aesthetic point and love glass fronted office buildings and I won’t reject the conversation with anyone who wants to mount shutters on their office. I see the main opportunity for shutters as being in the residential market. The number of houses that have closed curtains during the day tells me there is a need. Inclusion on the Green Deal tells me there is a value and Part L tells me there will be a requirement.

The second conversation was equally worrying, a previous experience some years ago was not a good one. The impression was that all shutters were mounted externally and ugly. If you want external and ugly, I can do that, but I would be looking for architects to make full use of the internal boxes that are available and designing them in. This led onto another problem based on experience that shutters were mounted on a doctor’s surgery, and the experience was not good. The built in headboxes, which contradicts the first point, did not allow the simplest maintenance to be undertaken, giving all involved headaches. Designs have moved on. There are headboxes available that are designed with maintenance in mind. The modern era sees headboxes where the whole mechanism and shutter can be removed from inside the building. Manual operation changed for motors, guides can be built in rendering the shutter almost completely hidden when not in use.

I was a little surprised at these attitudes towards shutters.

Back to the exhibition, I met some wonderful people who were working very hard in the face of trying conditions. Footfall, or lack of. Attendance appeared to be very poor and more than one exhibitor expressed their dissatisfaction hinting that next year’s event would be the opportunity to make money by not spending on a stand. We come back to the lack of signage at the entrance, marketing would appear to be low key. was this a contributary factor?

I know that self build is a small part of the market, but there are opportunities there to be taken.

I am not going to speculate on the reasons why, and would love to see this becoming a future event in the calendar and would consider putting my hand in my pocket for a stand. Clearly there is a lot of educating to be done and an exhibition is the perfect place.

It would be a terrible shame to lose what could become a wonderful show.