Co1

Thanks a lot John, makes sense.

I’m building a porch at the moment. The whole thing is sheathed and wrapped in breather membrane, and has 150mm of PIR in walls and ceilings (or will have when finished) and 100mm in the slab. It will not be heated on the basis that it is a porch!! The question is whether to fit a vapour barrier internally. The porch will be used to clean off wet dogs and store damp boots and jackets in winter. My concern is that the vapour barrier will actually keep all the damp in there, and I’d much rather it permeated out. Am I out with my logic on this? Thanks Col

Any thought on whether this non breathable membrane would serve the same purpose: https://timbakit.co.uk/products/sark-it-non-breathable-waterproof-roofing-membrane-1-x-15m?srsltid=AfmBOoo4PrL-rBld88qiIJTI-JI9QFvglaBukMHjRjGNKg9NcSz-Gyex Failing that, I have found a local ( ish) merchant with stock of AF1 at £80 +vat. 😳

Thanks. I found that but they want £25 to ship it. I fear that where I’ll end up going mind!

Very kind of you goodbyegti, but unfortunately I’m in North Yorkshire. I might end up doing the same as you though; buy a roll and give the rest away.

All the best practice I read says I should be using af1 builders paper under the lead when I renew a valley next week, but half my builders merchants haven’t heard of it, and the other half don’t stock it!! Is there an alternative? I also had a Quick Look over YouTube vids of valley replacement and didn’t find anyone using it!! I don’t want to cut any corners, but am I creating a rod for my own back by trying to track some down and use it? Any help would be appreciated. Thanks Col

I messaged Cromar last night, and at 09:04 this morning they confirmed that it wasn’t suitable. Impressive customer service!

Thanks all. I’ve reached out to the manufacturer to see what they say, but as I mentioned, it doesn’t seem right! The help is very much appreciated.

My merchant tells me I’ll be fine using this product as the internal vapour barrier on my timber framed extension. https://www.roofingsuperstore.co.uk/product/cromar-vent-3-high-performance-breather-membrane-50m-x-1m.html Is he correct? I’m hoping so as I have a load of it left over from another job, but it feels a bit wrong!! Thanks Col

Thanks Syne, you are right, they are common on council housing in the area. Our house has a small extension, but whomever has done it hasn’t matched the originals and it drives me mad!! I need about 300 for a dwarf wall around a proposed timber frame extension. I don’t suppose you came across a name for them did you?

Or how I can find out. They are from a 1950’s house in north Yorkshire and are pretty common and distinctive with their patterned finish, which I think is supposed to fake a bit of weathering. Any ideas? Thanks Col

The original front door will stay in place as an inner door. There will be a new door on the front of the porch facing the roadside.

According to the planning portal it does. There will be a bit of a delay between them, porch is in May, rear extension is in August.

Thanks Nod, much appreciated.

Thanks a lot. Am I right in not paying this until planning is granted, on the basis that planning might be refused and I will have wasted the cash?