Methodology
We compare products on published specs, not tested. Every figure links to the maker's or a UK retailer's page, with the date we checked it.
Where our figures come from
How often we check
How our tools work
Each tool uses only the numbers you enter and shows a worked example and the formula. The roof load checker never estimates a static roof load from a dynamic one.
What we don't do
We don't give star ratings, scores or winner badges, and we don't show live prices: check the current price with the retailer.