AF1 under lead?

[Co1]

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

[garrymartin]

Isn't it A1F? 

 

"reinforced bitumen-bonded building paper laminate"

 

It might be why people can't find it at builders' merchants if they are searching for AF1 in their systems. Loads of places have it in stock online.

 

As to whether it should be used or not, sorry, can't help there.

[Nickfromwales]

https://www.buyinsulationonline.co.uk/product/novia-a1f-building-paper?gad_source=4&gad_campaignid=22149925402&gbraid=0AAAAAolHs116snL13ZrLXATGXtAl0ng5L&gclid=Cj0KCQjwoZbBBhDCARIsAOqMEZUWvJ23gaPqHoGM1WgXfutk1-neASiKkpZE0KoCZTsh0mwEStg5KcIaAsLCEALw_wcB

[nod]

I’ve used it 

It stops the lead sweating 

[goodbyegti]

I've got about 35m of a1f in Bristol if interested. I used it on my parapet.

 

You can have it for free. Maybe a little donation to Buildhub?

[Co1]

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. 
 

[Co1]

3 hours ago, Nickfromwales said:

https://www.buyinsulationonline.co.uk/product/novia-a1f-building-paper?gad_source=4&gad_campaignid=22149925402&gbraid=0AAAAAolHs116snL13ZrLXATGXtAl0ng5L&gclid=Cj0KCQjwoZbBBhDCARIsAOqMEZUWvJ23gaPqHoGM1WgXfutk1-neASiKkpZE0KoCZTsh0mwEStg5KcIaAsLCEALw_wcB

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

[Co1]

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. 😳

[Nickfromwales]

2 hours ago, Co1 said:

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

That was just a random internet grab, so shop around.