C16 roof timber protection

[shd1970]

I’m about to start my garage roof extension project using C16 joists before overboarding with OSB and felt.
As I will be fitting this diy project in around my day job, it may take me longer than I would like and as we are in winter, it’s got me thinking about whether I should protect the rafters before the OSB and felt is able to go on

Can anyone confirm if I should protect with some plastic sheeting please or is it not necessary ?

TIA

 

[23vc]

Not necessary, particularly if you use treated timber. Even if you didn’t, it probably still wouldn’t be necessary in the scheme of things

 

[shd1970]

Not necessary, particularly if you use treated timber. Even if you didn’t, it probably still wouldn’t be necessary in the scheme of things

thanks 23vc

when you say treated, is it an option from the supplier when purchased, or just a standard wood/outdoor preservative that you are referring too please ?

 

[23vc]

Option when purchased. Tannalised. Go for that in any case, can’t see any reason not to

 

[^woody^]

Whilst ok to leave exposed in the context of it will eventually dry out and won't rot, however all construction materials should be covered as soon as possible and not left exposed unnecessarily for extended periods. A few days maybe, but weeks no.

What will happen with saturated joists is they can sag, and can also twist and deform after rapid drying cycles.

You could try and sheet over them with a tarp and a few timber battens. It won't need to be perfect but as long as most of the rain is kept off. But this may be impractical. In which case, consider installing a few joists and then fitting the deck sheets, and this will then be easier to cover. Then extend the cover as you add further joists and OSB sheets. Also, be sure to fit all noggins and bracing and not leave the joists without them if they might get damp - that includes atmospheric damp from mist and fog, or tranalised timber that is still damp from the process when delivered.

 

[shd1970]

Whilst ok to leave exposed in the context of it will eventually dry out and won't rot, however all construction materials should be covered as soon as possible and not left exposed unnecessarily for extended periods. A few days maybe, but weeks no.

What will happen with saturated joists is they can sag, and can also twist and deform after rapid drying cycles.

You could try and sheet over them with a tarp and a few timber battens. It won't need to be perfect but as long as most of the rain is kept off. But this may be impractical. In which case, consider installing a few joists and then fitting the deck sheets, and this will then be easier to cover. Then extend the cover as you add further joists and OSB sheets. Also, be sure to fit all noggins and bracing and not leave the joists without them if they might get damp - that includes atmospheric damp from mist and fog, or tranalised timber that is still damp from the process when delivered.

thanks for the comprehensive reply woody !