Roof sheathing

[emmaamme]

My house is 7 years old and when in loft yesterday I noticed the roof sheathing at some of the joints are not butting up against each other. In particular this one where i can see the felt through the gap (pics 1-3)

Here are some others -

There's no evidence of water getting in. Is this quite common and nothing to worry about?
Thanks.

 

[Alastairreid]

The gap between the boards is for expansion.

 

[emmaamme]

Thanks Alastair. Does it matter that one of the ends of the boards is hanging down lower than the other one as if it's bowed a bit (pic 2)?

 

[Alastairreid]

Won't cause any problems. The ply is to strengthen the trussed roof.
Are you in Scotland.

 

[Burnerman]

Hi Emma
As you live North of the border I guess we can see sarking sheets of ply rather than the more traditional tongue and groove planks.
For sure, I’d leave things well alone as the roof shell will be very strong and ply can warp under it’s own weight.
Regards!
John

 

[emmaamme]

Thanks everyone, I really appreciate you getting back to me. Yes Alastair I'm in Scotland. Hope all is good with you John.

 

[emmaamme]

Sorry last question (I promise). One of the boards seems to have a crack along it. I take it that's ok too? This is on the roof slope - just the angle makes it look like it's a wall.

 

[Burnerman]

No need to worry about that one Emma - sheet material such as this often has splits and it's only through one layer of veneer.
Ply such as this (it's actually a material called 'stoutheart' as far as I can see) doesn't need to be of first quality as such volumes would be expensive, hence it's use here.
Regards
John

 

[emmaamme]

Thanks so much John. Note to self - stay out of the loft . Hope you have a great day. Take care

 

[Burnerman]

Great to see someone taking so much care and interest in their home, Emma!
Regards
John

 

[^woody^]

Won't cause any problems. The ply is to strengthen the trussed roof.
Are you in Scotland.

Wouldn't there be a noggin there to support the two edges of the ply?

 

[Alastairreid]

Makes for a better job imo but on new builds they don't.

 

[emmaamme]

Just curious - are noggins usually behind the plywood or in front ie visible from the loft?

 

[Burnerman]

Visible from the loft, Emma - you could put some in but I'd strongly resist any hammering!
You could tape over the joints to prevent draughts - if any - but it isn't needed.
John

 

[emmaamme]

Thanks John - just wondered how it worked. I'll not be messing with anything ha ha