58
EXTERNAL ENVELOPE
New guidance helps housebuilders combine in-line solar PV and air permeable underlays
N PV together with Proctor Air®
ew guidance from Proctor Group means housebuilders can now use integrated (or in-line) solar , confi dent
that they are meeting all relevant technical requirements – including the NHBC’s 2024 Technical Standards, with an alternative BBA approved solution which negates the requirement for double battening. Backed by leading moisture experts in the UK and Europe, the guidance is also refl ected in an update to Proctor Air’s BBA certifi cate. That means designers and specifi ers can follow the guidance in the knowledge that it has been assessed by an independent third party. As an air permeable, low resistance (APLR) membrane, Proctor Air reduces the risk of issues occurring in roof spaces due to poorly installed vapour control layers or ventilation. And because it provides a more uniform fl ow of air than standard ventilation solutions, it means the roof requires no other
ventilation measures. Proctor Air has proved a popular solution since its launch. However, an update to the NHBC Technical Standards created confusion around the use of in-line solar PV with APLR membranes. Housebuilders and developers have therefore been reluctant to specify the two together, despite wanting to use APLR products. With rooftop solar expected to be made compulsory on new-build housing, the adoption of PV panels will only intensify
as specifi cations adapt to the lower carbon emissions required by the Future Homes Standard. And as those same homes become even better insulated and more airtight, they will rely on the performance of air permeable membranes to help reduce condensation risk in loft spaces. To overcome the confusion, Proctor Group undertook research to investigate the issue, engaging Glenfeulan Consulting to undertake modelling using RoofCond software. The renowned Fraunhofer Institute then validated the reasearch fi ndings and agreed with the conclusions.
Equipped with a more thorough understanding of air and moisture movement through
pitched roof coverings, Proctor
Group has developed a recommendation for pitched roof specifi cations featuring in-line solar PV and Proctor Air.
01250 872 261
proctorgroup.com/products/proctor-air
WWW.ARCHITECTSDATAFILE.CO.UK
ADF NOVEMBER/DECEMBER 2025
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76
