Wall insulation
Author
Discussion

dba7108

Original Poster:

675 posts

189 months

Saturday 20th September 2025
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Ive converted my garage which has an exterior brick and then block construction. House is 1990. Il batten inside then plasterboard. What is the best insulation. A pir type or rock wool fluffy type. Advice please.

LooneyTunes

8,657 posts

179 months

Sunday 21st September 2025
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PIR is much more effective, with the effect that your buildup can be thinner:
wall —> vertical damp proof membrane —> treated timber batten —> PIR —> board

Make sure you can find long enough players board screws

To do it properly, tape the joints of the PIR for vapour control or use a separate membrane.

When it comes to fixing the batten, don’t mess around drilling holes, using plugs, lining it all up: drill all the way through the batten and into the wall in one go before using hammer in fixings (they look like a long screw with rawlplug already attached). It is much quicker, assuming of course the walls are all nice and flat.

if you’re doing it by the book/to meet building regs, the likes of kingspan and reticel have calculators for performance and diagrams etc.

lrdisco

1,668 posts

108 months

Sunday 21st September 2025
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Use these for fixing battens to the wall-
https://www.screwfix.com/p/easydrive-tx-countersun...