Are free MVHR designs any good?

Lately we’ve been seeing a few MVHR manufacturers offering “free” MVHR ductwork designs with their product sales. If you’re planning an MVHR system in 2022 for your build project you will have likely been offered or found a free MVHR design service yourself. At Heat, Space and Light we charge for our MVHR detailed ductwork … Read more

How to work out the Passive House Form Factor

Complicated form of a UK home dormer will require more insulation as proportion of external area to floor area increases

The Passive House Form Factor quantifies the relationship between the living area of the building and the total amount of surface area that heat can escape from. The calculation is simple: Total heat loss area ÷ floor area = Form Factor The Form Factor of a building is key in low energy design because it … Read more