We had some loft boarding installed and they took off two of the inner diagonal truss braces at one end. I think they did this to help installing the boards. They didn't reinstall them or mention them afterwards. They probably overlooked them as I didn't find them straight away as they were down the side of the boarding on the insulation.
Are these inner braces actually needed? There is more substantial diagonal and horizontal bracing on the rafters elsewhere.
Are they are only temporary bracing while the roof was built? In Scotland if that makes any difference to the regs
Are these inner braces actually needed?
Yes
Are they are only temporary bracing while the roof was built?
No, temporary bracing will be used when setting out the trusses, typically something like roofing batten, but not as diagonal bracing.
Edit : I wouldn't panic if it's just a couple and there are plenty more, but you might as well nail them back on.
They probably overlooked them as I didn't find them straight away as they were down the side of the boarding on the insulation.
I'd suggest they were hoping you'd overlook them, but putting them somewhere that you'd not find them straight away 🙂
To be fair, they were each laid on the side they came off and in the right orientation. If they'd wanted to hide them they could have put them together under the new boards.
you might as well nail them back on
They're back on now, simple enough. The nails were left in the boards
Hmm. Now you've all got me worried, I took some of those off when I partly boarded our loft a couple of years ago. Maybe I'd better reinstate. Essentially they were just In The Way all the time, and I kept clouting my head on them. That said, roof's not gone anywhere in the meantime. What do they do?
In Scotland, roofs are fully covered with sarking so I suspect these braces were installed to align the trusses during construction, so probably of little structural value, particularly when you look at the size of the timber concerned. I have looked at photos of the inside of my house roof during construction and there are only lightweight braces - I’m in the Hebrides and we get 50mph+ winds regularly
What do they do?
Diagonal bracing provides stability to roofs under wind loads and helps to resist lateral movement. But the boarding that you fixed might have done that anyway. If it was ply or sterling boards definitely, if it was plasterboard not so much so but I'm guessing that it might help a bit.
I don't think we have sarking..... it would be visible on the inside right?
sarking should be - can you see roofing felt or the back of the slates?
look at the size of the timber....
Roofing felt/membrane on the inside. House was built about 10 years ago
unusual for scotland - but i guess your in the lowlands.
Roofing felt/membrane on the inside. House was built about 10 years ago
No sarking then - as trail rat says. Diagonal bracing is needed then
Have you actually pushed the membrane/felt to feel whats behind. I would be amazed if its not got sarking up there.
its not going to work very well at bracing. Well it will for the first three maybe but the one with the light is effectively unbraced.
Based on the size and the fact its barely nailed in i am going with temporary brace left in.
Nothing helpful to add - but to point out the no-one's taken the opportunity to suggest replacing with lettuce as it's longer lasting than trusses..
Based on the size and the fact its barely nailed in i am going with temporary brace left in.
You can tell from the photo? I can't see any nails!
It needs to be 4x1 and double nailed to provide effective diagonal bracing.
You can tell from the photo? I can't see any nails!
There isn't sufficient width to space the nails out to resist the rotation loads it would be trying to resist.
Its also in the wrong place. The actual brace is nailed to the rafter in the background. As you say 4x1 by the looks of it.