Felt and snow

[readiescards]

If my roof is partially constructed to the state of being felted and latted, is a snow fall going to be bad news? 

 

 

[ToughButterCup]

Well, put it this way, Santa will have a better foot hold. 

[ProDave]

It took me about 3 months to tile my roof over last winter, during which time a lot of snow fell on the roof and nothing came to grief. So as long as the felt is good there should be no worries.

 

At least you will get a chance to find and fix any leaks in it before the final roof covering goes on.
 

[TerryE]

All roof felts should be a non-tenting type, so the the snow shouldn't be an issue. IMO, strong winds are going to be more of a risk.  Ours was felted when the frame was put up in Nov 2015, but the slates didn't go on until early February.  We went around ours and made sure the overlaps were properly stapled down (our roof is sarked) so that there were no lifts or pockets where strong winds could get under the felt.  We also put some temporary battens along the verges for the same reason.  We had no problems.

[ProDave]

That's a god point. A Scottish roof with sarking board is much more robust. an English roof with just the felt stretched across thin air between the rafters will not be as robust.
 

[TerryE]

2 hours ago, ProDave said:

 A Scottish roof with sarking board is much more robust.

 

@ProDave, This is in the Scottish BRegs isn't it?  Yet in rest of the UK roofs are rarely sarked.  Our timber frame' warm loft roof was sarked during erection, and the frame is just so much more rigid and weatherproof.  

[ProDave]

Yes that's right, Scottish building regs demand a sarking board. It does make a far far better roof structure and even if I was building outwith Scotland I think I would do it.
 

[AliG]

Our current roof in Edinburgh isn't sarked (is that a verb?). I think it's normal practice but you don't have to have sarking.

[TerryE]

@AliG, but when was it built?  BRegs do change over time, but are applied retrospectively.

[AliG]

True, it is 13 years old. But I think it is more tradition. I will see if I can find the reg

[AliG]

There is reference to two kinds of roof construction here under the fire regs.

• in the case of a pitched roof covered by slates nailed directly to sarking and underlay, the junction between the sarking and wall-head should be fire-stopped as described in BRE Housing Defects Prevention Unit “Defect Action Sheet (Design)” February 1985 (DAS 8), or

• in the case of a pitched roof covered by slates or tiles fixed to tiling battens and any counter-battens, the junction between the tiles or slates and the underlay should be fully bedded in cement mortar (or other fire-stopping material) at the wall-head.