Many social landlords have made great strides in improving the energy performance of their homes over recent years – but isn’t all the easy stuff done? Painstaking work by a leading insulation company has uncovered another ‘quick win’.
Party walls – those shared between two adjoining buildings or rooms – were until now thought to be off-limits for insulation measures. But investigations by Knauf Insulation have revealed the potential for treating them to have a significant impact on cutting bills and reducing carbon emissions. Many homes built since in the 1950s and 60s have party walls with a cavity. Because both buildings are heated, it was previously assumed that the amount escaping would be zero or very little.
But now Knauf, in conjunction with Leeds Metropolitan University, has blown this apart. They found that significant amounts of heat are lost via the phenomenon of ‘party wall bypass’. This is where cold air moves in from the outside building elements which has resulting in heat loss via convection. The testing demonstrated that the level of heat lost through party wall thermal bypass is so high that it is now recognised in Building Regulations through Part L for new homes – and also RdSAP for existing ones. This means that it is also now eligible for funding through ECO.
The research identified that filling in the gaps with insulation could boost the SAP rating of some homes by as much as 5 points – about the same as Solid Wall Insulation. As it is a relatively low cost measure with a short payback period it should be an attractive option for landlords looking to push forward on energy efficiency without significant cost.
And carbon can be claimed on both sides of every treated wall – typically 6.9 tonnes for homes with two party walls and 3.4 tonnes for those with one.
Knauf have used the insights from the research to design and develop a method to infill cavities that are affected which is simple, quick and un-intrusive to install. Their ‘Supafil’ insulation is the most widely used product for existing cavity walls in the UK.
What does all this add up to? Well, if all the estimated 5 million homes that this is thought to affect in the UK were treated, CO2 emissions could be reduced by 2.5 million tonnes, and £465 million wiped from energy bills every year.
As 2050 emissions reduction targets become more ambitious, infilling party walls provides an easy, quick win – something an under-pressure social sector will surely pick up like a shot.
Click the button below to find out more and arrange a meeting or phone call to discuss how you can boost your SAP with this ECO-funded measure.