Felt roof nail holes

[dimstthomas]

Hello

We build a self assembly log cabin four years ago. It came with a felt roof and we followed the instructions on nailing the felt down. Yesterday we noticed a couple of small leaks inside the log cabin. Looking at the roof today, the felt is broken around several of the nails, see photos below. Is this because we did something wrong or is it due to poor quality felt?

 

[Burnerman]

Its not the best move to nail felt at any time, especially on a horizontal run if you can help it - expansion and contraction cause what you see.
Go over the nails with a brushing solution such as Evercryl or Acropol to seal things up again.
John

 

[dimstthomas]

Its not the best move to nail felt at any time, especially on a horizontal run if you can help it - expansion and contraction cause what you see.
Go over the nails with a brushing solution such as Evercryl or Acropol to seal things up again.
John

Thanks for the reply. How do you attach the felt without using nails? We built a smaller shed at the same time that doesn't show this problem, but the log cabin is in direct sunlight all day long so I guess this would cause more expansion and contraction?

 

[vinn]

You should have originally used some kind of "stuck-down" felt such as "peel and stick". You now have the nail hole issue and rippling and bubbling can be seen, which means moisture has penetrated below the surface felt layer. In the long run, whatever that is, your felt roof is shot.
Maybe the original instructions meant to nail down the first layer of felt only?

 

[alan333]

For a permanent solution nail the existing felt at about 300mm centres, then lay a layer of torch-on mineral surfaced felt using a gas torch.

 

[^woody^]

Is this because we did something wrong or is it due to poor quality felt?

The felt has lifted, normally due to wind suction, and this has pulled on the nail heads. Too few nails or poor design. Although stiffening of the felt due to age (and quality) may contribute.

It might be OK on a shed due to a smaller area of roof.

 

[chappers]

I would agree with that, even for a shed roof I would have probably put another 5 nails between those two