ADL 2021, what’s changed?

We could not start this month’s column without first recognising the atrocities being perpetrated by the Russian Government and sending a message of support to the people of Ukraine. 

In addition to seeing the terrible images of the Russian invasion we are all feeling the financial impact of the war through our energy bills, which were already rising at a record rate. These increases in energy costs, together with the impacts of climate change, come at a time when the English Government has launched its much-awaited changes to Approved Documents Part L and F; plus introduced a new regulatory document Part O Overheating.

So, what has changed and how will it impact roofing contractors and roofing suppliers?

To start with there are now 2 Approved Documents rather than the previous 4 documents. From there the changes get more significant. New rules come into force in June 2022* requiring a mandatory 30 per cent cut in carbon for all new homes with a 27 per cent cut for other buildings, including offices and shops. Minimum efficiency standards are introduced for both new and replacement thermal elements (walls & roofs), windows and doors.

A new ‘principal performance metric’ will be introduced which will increase the demand for solar photovoltaic (PV) systems on roofs bringing both opportunity and risk if 3rd party trades work on the roof.

At QI we expect to see the improvements in both the notional U-value of a dwelling roof (from 0.13 W/(m²K) to 0.11 W/(m²K)) and the maximum U-value of a dwelling roof (from 0.20 W/(m²K) to 0.16 W/(m²K)) resulting in the thickness of the most commonly used insulation boards on projects increasing, along with the cost of a suitable thickness of insulation. Improvements in U-values are also required in the refurbishment of dwellings and non-dwellings.

Which is why QI are so pleased to see our XPS insulation partner, Ravago Building Products, take a proactive approach to helping contractors and waterproofing manufacturers manage their project costs by introducing a new range of insulation board thicknesses targeted at achieving a specific U-value, rather than manufacturing in a simple range of 10mm increments.

When looking at a price list for these new thicknesses you would be forgiven for thinking they look a bit odd, but when you appreciate the U-value they achieve, it becomes clear that this is a strategic decision aimed at reducing the over specification of insulation board thickness. Congratulations on some forward thinking Ravago.

Thickness (mm) U-value W/(m²K)
115 0.25
145 0.20
175 0.17
190 0.16
195 0.15

*there is a 1 year transition period allowing for existing applications to process.

Next month: Corrected thermal calculations for inverted roofs