Not been on this forum for a while (other things going on), so forgive me if this is old news.
This article is suggesting a change needs be made to way that U-values are calculated for Energy Performance Certificates which are used in house sales. But I am wondering - if U-values should be calculated differently does that also affect how building regs are applied? And on both scores is anything going to actually be done about it?
http://www.telegraph.co.uk/wirecopy...-as-traditional-buildings-more-efficient.html
The Society for the Protection of Ancient Buildings has shown that techniques for assessing the efficiency of modern buildings are being wrongly applied to old ones.
Traditional house-building materials including cob, stone and timber work in different ways from those erected from newer materials such as concrete, metal and modern brick.
The "U-value" system of working out how heat-efficient walls are was designed for the modern materials.
The system forms part part of the Energy Performance Certificates applied to all properties that are sold.
Older buildings score poorly in terms of U-values, but are efficient in their own way because they "breathe".
Those in old homes who realise they have a poor U-value score often use waterproof materials, add damp courses and attempt other "improvements".
However, this might well have a negative effect on the properties and make them colder because it traps in damp.
SPAB's research is the first to look at old properties and has shown that the U-value system is totally inappropriate to judge them.
It's estimated that 20 per cent of properties would be inappropriately assessed with the U-value system, including Victorian and Edwardian terraces.
These properties - built prior to World War One - have more in common with mediaeval homes than modern ones.
Jonathan Garlick from SPAB said: "We discovered that 79 per cent of traditional buildings were more efficient than we thought.
The U-value system was designed for modern materials and has been wrongly applied to traditional buildings.
It's not that the U-value system is wrong, it's just that it's being wrongly applied.
People are over insulating their homes when they don't need to. These old materials work, so if it's not broken, don't fix it.
There are pressures from the green agenda about insulation which are fine for modern buildings that are designed to let nothing in.
But older buildings have materials that absorb damp and then allow it to evaporate.
They live and breathe and work in different ways from buildings made from modern materials.
Amazingly no-one has ever carried out this type of research and it shows that materials such as cob, stone and timber should not be assessed in the same way as concrete, modern brick and breeze blocks.
If owners of traditional buildings are guided by their U-values then they might begin to try and "improve" them.
But to add damp courses and wall insulation could trap in damp and make the home colder which would mean it would take more energy to get it warm again.
An old home will see that the damp evaporates and a dry home is then easier to heat - and it will retain the heat.
We used to treat buildings as living things, but now they are regarded more as machines.
Traditional buildings didn't really need foundations because of the way they were built.
Now we tend to just look for strength which means much bigger foundations.
We are continuing the research and hope to get the message out there that older homes should not necessarily be treated as new ones are.
Cob cottages, for example, are well known for being warm in the winter and cool in the summer.
Old brick buildings are also different from newer ones because bricks are now fired at much higher temperatures, which changes the way they work.
People traditionally built houses based on hundreds of years of experience working with local materials. They knew how they worked.
New homes are now the same across the country and will benefit from waterproofing and insulation.
But to apply those techniques to traditional materials is not going to work."
Dr Caroline Rye from the University of Portsmouth who carried out the research on behalf of SPAB said: "When you sell a property you need an Energy Performance Certificate.
Part of that includes the U-value and buildings that are pre-1919 will inevitably get a poor figure.
So people might be minded to carry out inappropriate work through market pressures.
It is not just the materials used but the way the walls were built. If you judge traditional buildings by modern standards you get inaccurate results.
If you test the efficiency of traditional walls using different methods you get better results.
When traditional buildings were erected they weren't thinking of heat efficiency, they were thinking of keeping the weather out - which might just happen to be good for heat efficiency.
They were concerned with fuel efficiency as we are now because they had to go and cut the wood down themselves.
This article is suggesting a change needs be made to way that U-values are calculated for Energy Performance Certificates which are used in house sales. But I am wondering - if U-values should be calculated differently does that also affect how building regs are applied? And on both scores is anything going to actually be done about it?
http://www.telegraph.co.uk/wirecopy...-as-traditional-buildings-more-efficient.html
The Society for the Protection of Ancient Buildings has shown that techniques for assessing the efficiency of modern buildings are being wrongly applied to old ones.
Traditional house-building materials including cob, stone and timber work in different ways from those erected from newer materials such as concrete, metal and modern brick.
The "U-value" system of working out how heat-efficient walls are was designed for the modern materials.
The system forms part part of the Energy Performance Certificates applied to all properties that are sold.
Older buildings score poorly in terms of U-values, but are efficient in their own way because they "breathe".
Those in old homes who realise they have a poor U-value score often use waterproof materials, add damp courses and attempt other "improvements".
However, this might well have a negative effect on the properties and make them colder because it traps in damp.
SPAB's research is the first to look at old properties and has shown that the U-value system is totally inappropriate to judge them.
It's estimated that 20 per cent of properties would be inappropriately assessed with the U-value system, including Victorian and Edwardian terraces.
These properties - built prior to World War One - have more in common with mediaeval homes than modern ones.
Jonathan Garlick from SPAB said: "We discovered that 79 per cent of traditional buildings were more efficient than we thought.
The U-value system was designed for modern materials and has been wrongly applied to traditional buildings.
It's not that the U-value system is wrong, it's just that it's being wrongly applied.
People are over insulating their homes when they don't need to. These old materials work, so if it's not broken, don't fix it.
There are pressures from the green agenda about insulation which are fine for modern buildings that are designed to let nothing in.
But older buildings have materials that absorb damp and then allow it to evaporate.
They live and breathe and work in different ways from buildings made from modern materials.
Amazingly no-one has ever carried out this type of research and it shows that materials such as cob, stone and timber should not be assessed in the same way as concrete, modern brick and breeze blocks.
If owners of traditional buildings are guided by their U-values then they might begin to try and "improve" them.
But to add damp courses and wall insulation could trap in damp and make the home colder which would mean it would take more energy to get it warm again.
An old home will see that the damp evaporates and a dry home is then easier to heat - and it will retain the heat.
We used to treat buildings as living things, but now they are regarded more as machines.
Traditional buildings didn't really need foundations because of the way they were built.
Now we tend to just look for strength which means much bigger foundations.
We are continuing the research and hope to get the message out there that older homes should not necessarily be treated as new ones are.
Cob cottages, for example, are well known for being warm in the winter and cool in the summer.
Old brick buildings are also different from newer ones because bricks are now fired at much higher temperatures, which changes the way they work.
People traditionally built houses based on hundreds of years of experience working with local materials. They knew how they worked.
New homes are now the same across the country and will benefit from waterproofing and insulation.
But to apply those techniques to traditional materials is not going to work."
Dr Caroline Rye from the University of Portsmouth who carried out the research on behalf of SPAB said: "When you sell a property you need an Energy Performance Certificate.
Part of that includes the U-value and buildings that are pre-1919 will inevitably get a poor figure.
So people might be minded to carry out inappropriate work through market pressures.
It is not just the materials used but the way the walls were built. If you judge traditional buildings by modern standards you get inaccurate results.
If you test the efficiency of traditional walls using different methods you get better results.
When traditional buildings were erected they weren't thinking of heat efficiency, they were thinking of keeping the weather out - which might just happen to be good for heat efficiency.
They were concerned with fuel efficiency as we are now because they had to go and cut the wood down themselves.