- Joined
- 15 Jun 2019
- Messages
- 31
- Reaction score
- 0
- Country
Hi all just looking at cutting birdmouths and noticed some people cut two, one for wall plate and one for the ledger board is two better or is one sufficient? Cheers
Hi all just looking at cutting birdmouths and noticed some people cut two, one for wall plate and one for the ledger board is two better or is one sufficient? Cheers
It's more borne from a horrible experience we had with a badly built wall that we were attaching a lean-to roof against. The rigid nature of two BM's meant that either the wall plate shoved out or the pole plate was shoved up out of level at one end.Even with truss clips, nosey. I am disappointed.
Good question surely the force at the top of the rafter is pushing against the ledger or ridge board (depending on the roof type) and the bottom part with birdsmouth is pushing down on the wall so is another birdsmouth really needed at the top.Why would you have two........................ever
No. As long as the plumb cut is sat against the masonry. The truss clips will prevent uplift.so is another birdsmouth really needed at the top.
Purlins etc.Why would you have two........................ever
Gravity tends to push downwards, and seating rafters has tended to work well for the past few thousand years, but hey you could be on to something with this wild west method of roof framing.Good question surely the force at the top of the rafter is pushing against the ledger or ridge board (depending on the roof type) and the bottom part with birdsmouth is pushing down on the wall so is another birdsmouth really needed at the top.
A birdsmouth at the bottom is needed that’s without question it’s the top one I can’t understand surely pushing against the stone/brick wall of the house is better than a strip of wood ie the ledger board also what size timber would you recommend for the ledger board does it need to be the same size as the rafters.Gravity tends to push downwards, and seating rafters has tended to work well for the past few thousand years, but hey you could be on to something with this wild west method of roof framing.
In fact why have any birdmouths, when a couple of nails will hold it surely?
You mean like a rafter that is positioned between a valley beam and a ridge beam.In fact why have any birdmouths, when a couple of nails will hold it surely?
The situation you describe with the valley, means that the Jack rafter and valley rafter are in compression at the valley rafter connection with restrained vertical loading, and the whole roof works as one.You mean like a rafter that is positioned between a valley beam and a ridge beam.
….or a rafter that is secured against solid masonry with a top plumb cut. The pole plate is there to space the rafters and prevent uplift. Get over it Woods.
But the truss clip can bend horizontally if the rafter is pulled sideways. The clip provides zero lateral restraint.No. As long as the plumb cut is sat against the masonry. The truss clips will prevent uplift.
Says the man who informs us that gravity works downwards.sideways
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local