Sealing future energy efficient homes
Andy Swift, sales and operations manager for Iso-Chemie, says building regulations requiring windows to be ever more airtight will drive an uplift in energy efficient homes.
Changes to Part L of the Building Regulations are the driving force behind stricter standards and compliance procedures around energy and ventilation performance, contributing towards a roadmap to a net zero carbon future and new homes having to fall in-line with stricter carbon emissions targets.
This comes against the backdrop where evidence points to doors and windows as the main source of the nation’s chronically energy inefficient homes.
This is a pity because with advancements in cost effective, easy-to-use technologies, there’s never a justifiable reason for avoiding the specification of better energy efficient window and door sealing solutions.
Air tightness improvements
In this respect, the most recent changes to Part L will have to be seen as a step in the right direction for the new build fenestration sector.
These include improvements in air tightness, from 10 air changes per hour down to five air changes per hour and a requirement that the frame should be linked back to the wall with an airtight tape.
Heat will always find the fastest exit as it comes up against the ‘A’ or ‘A+’ rated window, and invariably this emanates from the 10mm or so expansion gap left around the window following fitment. This is normally left empty, but some amount of spray foam can be injected to fill the void before a silicone trim is applied for a smart looking finish.
Unfortunately, none of these solutions create a measurable, long term, high performance thermal, acoustic or airtight barrier – the U-Value of the installed window is simply reduced.
That’s why the house building industry and wider construction sector deserves better insulating solutions to improve energy efficiencies.
In modular construction, which continues to gain traction – industry sources estimate that out of the 200,000 homes currently constructed annually, about 15,000 of them are modular – house designers and specifiers are looking at new ways to deliver low carbon structures, which use sustainable technologies to deliver measurable airtight, acoustic and thermal sealing benefits.
And this is where self-adhesive foam sealing tapes can add real value, enabling developers to bring forward housing projects more expediently.
They can use ‘smart’ foams impregnated with different substances to create a measurable U-Value as low as 0.6w/m2k, offer superb thermal insulation and can contribute to acoustic sound reduction by 63dB. As these installation tapes are completely weather tight against driving rain up to hurricane force wind speeds, installers can quickly apply them around the frame during initial fitting.
This provides the assurance that they have completed a comprehensive ‘A’ rated installation rather than just supplying an ‘A’ rated window.
Future Homes Standard
Building regulation changes are moving the fenestration industry closer to the requirements of the Future Homes Standard for dwellings.
The uplift in Part L of the regulations includes a requirement for new homes to produce around 31% less CO2 than current standards and a 27% reduction of emissions from other new buildings, including offices and shops.
By 2025, when all aspects of the Future Homes and Buildings Standards come into force, the Building Regulations will inevitably become even more strict, requiring new homes to produce almost three-quarters less CO2 when compared to current standards.
As sustainability continues to be of paramount concern in the development of low carbon and eco-friendly building projects, we will see technologies such as energy foam tapes, which can add real value during the initial and post construction phases, only grow in importance as the most effective solutions for sealing window and door frame expansion joints and gaps in houses in pursuit of attaining the Future Homes Standard.
It’s simply a matter of designing in these products.
