A Kent builder who is about to complete a house which he plans to rent out as an investment says its thermal efficiency is so great that he has no need to install gas central heating.
Simon Day is building a 120 sq m three storey house in Canterbury whose overall U-value will be 0.14 in both the walls and roof – far more efficient than is required under current building regulations.
And he says that even in December he needed to heat the loft room for only ten minutes to keep it warm all day.
Simon has installed all three products from the dual tested Actis Hybrid range which was designed with the specific aim of addressing the DECC recognised performance gap.
He used 90mm thick honeycomb structured insulation Hybris (which is available in thicknesses from 45mm to 300mm), along with vapour control layer HControl Hybrid on the warm side of the walls and roof and insulating breather membrane Boost’R Hybrid on the cold side.
Using the NHBC approved products, which covered a wall area of 200 sq m and a pitched roof area of 80 sq m, also helped Simon comply – ahead of time - with revisions to the new part L regulations which come into force in April, which require thermal bridging to be avoided where possible.
Simon explained: “Because of the low U-values achieved I decided that gas central heating is not necessary. This decision was made after the room in the loft was insulated. Even though it was December, the small electric heater used on site was only used for ten minutes in the morning to warm the whole floor and this was enough to keep the loft area warm all day. As I’m looking at renting the house I can save costs on gas safety certificates each year. I was stunned at just how quickly the property warms up and how well the heat was retained.”
Simon has used other Actis products on previous projects for their impressive thermal efficiency.
“I decided to use the Actis range in the walls and pitched roof of the new house I’m building as the fuel costs in my own house are minimal. Also, the ease of installing the products meant my labour was reduced by around 25% compared to installing traditional insulation materials.
“There are no fibres and no dust is created when you cut it, which means I didn't need a respiratory mask or any special clothes – I was almost as clean when I got home as when I started the job. Because it’s so thin it’s light and easy to manhandle – quite a bonus when you're up and down stairs with it. And you only need a van, not a lorry, to get it from the builder’s merchants. There’s practically no wastage as you just cut it to fit – which also means you don't have much to take away and dispose of at the end of the job.
“Because it’s squashed in between the rafters and studs as long as you cut it a little bit large you can squash it into fit which means there are no gaps. It really helps eliminate thermal bridging as well. You just need to cut it off the roll – no special equipment needed - and stick it in.
“The material costs were approximately three quarters of what I would have spent if I’d used traditional insulation materials to achieve the same thermal performance.”
* Caption: Hybris insulation product helped Simon Day achieve a U-value of 0.14 in both the walls and roof of his Canterbury self build.