A Better Way to Build
The UK needs more energy-efficient homes and buildings to meet the demand to reduce CO2 emissions and help mitigate the effects of climate change. But the materials and the processes of construction itself demand energy and result in CO2 emissions. Currently this ‘embodied carbon’ phase accounts for around a fifth of the whole life ‘carbon cost’ of a building. Increasing energy efficiency is likely to shift that balance, so that the embodied phase will account for the greater part.
If you’re not already building in timber frame, then perhaps take a look at the people who are. With the Code for Sustainable Homes becoming embedded in the way new homes are specified and built, can you afford to ignore the benefits of building in timber frame?
Timber frame is very responsive to market needs, so the commercial imperatives to cut costs and reduce waste can also continue to be met. In particular, the speed and efficiency of construction delivers the best economic solution for customers.
So, if you are interested in what timber frame can do for you: how timber frame can help you meet high levels of the Code, help you improve cashflow, efficiency and profitability, unlock the value from your sites in a way that is both fast and low-risk – then you will find useful information on the Website.
If you have any concerns or queries, please do get in touch. We have a free technical helpline and an ongoing research and development programme to help answer any questions you may have on timber frame.
Building to the Code
It was no surprise that the first prototype homes to reach levels 5 and 6 of the Code for Sustainable Homes were timber frame buildings. Unveiled at the BRE Innovation Park in 2007, these properties are now two years old and have been put through some rigorous testing.
The first message is that timber frame is ideally suited to the low and zero carbon agenda, says Steven Streets, UKTFA technical manager. “Housebuilders using timber frame find it much easier to achieve very high insulation levels, fewer defects and a more airtight building with extremely low embodied energy. So after many months of chasing after new technologies that could enhance performance we are now back to the fundamental understanding that getting the fabric right is the single most important place to start.
“Forget about sourcing fancy renewable energy systems to bolt onto leaky, poorly built, high embodied carbon homes. The emphasis should always be on fabric first. Thankfully, the Government is supporting this approach wholeheartedly, and it’s at the heart of the proposed Part L changes and the zero carbon definition.”
The Government’s determination to improve the sustainability and energy efficiency of UK homes led to the introduction of the Code for Sustainable Homes in 2006.
Code level 3 is already mandatory on developments on government owned land and most affordable housing schemes, and the target is to see all new homes reach Code level 6 by 2016.
To achieve the right amount of credits to demonstrate compliance with the Code, the key issues affecting a developer’s choice of construction method (typically a choice between masonry, timber frame or steel frame) tend to come down to two things: the energy efficiency of the building’s fabric, which can reduce the home’s overall energy consumption, and the environmental rating and sourcing of the building materials themselves. On both these things, timber frame scores particularly well. Most designers and developers already see timber frame as the most natural solution for Code compliance.
Another benefit has been identified in the newly published Comfort and Cost report which shows that the additional costs of achieving Code compliance are lower for timber frame than for masonry, especially for detached and end-of-terrace dwellings.
In broad terms, the report says, the cost of timber systems ranges from £130 to £190 per square metre. But the big issue for builders is the additional cost of compliance with the Code’s minimum heat loss parameters.
(the indication of the heat loss through the walls taking into account both fabric and ventilation losses – in other words, a tougher challenge than U-values alone). Critical CSH points are available for heat loss values less than 1.3, 1.1 or 0.8.
The new data shows that a builder aiming for a heat loss parameter of less than 1.3 would definitely be better off using timber frame construction. The cost differential is typically in the order of 2.2 per cent to 5.2 per cent (depending on the dwelling type), compared with masonry construction which could cost up to 20 per cent more.
Timber frame delivers the required performance for heat loss, airtightness and acoustics. “Of course, open panel timber frame systems do rely on good workmanship and site supervision to deliver the goods,” says UKTFA technical manager Steven Streets. “Closed panel systems can provide a higher degree of consistency.”
