Timber workshop Build - some questions

[mpooley]

Soffits on my Timber workshop?

It would be easiest to nail them to the bottoms of the overhanging trusses at an angle but i have never seen it done this way. Is there any reason that they are normally battened out and fixed at a right angle?


I have put DPC under the bottom rail and folded it 6 inches up the wall this is then covered by the wall wrap so that no water can get to the bottom timbers. I am then going to shiplap over that. My question is that i am thinking that the bottom plank of shiplap will get a lot of splashback and maybe i should replace it with 6inches of the fibre cement sheet roofers use as undercloaking.
Do you think that would be suitable?


Thanks

Mike

Oh 3rd question would that fibre cement be good to use as the soffit also?

 

[^woody^]

No reason why you can't do that with the soffit. Horizontal soffits are a design/economy thing where the external wall is finished off at window head height and the soffit used to cover the void. Fibre cement is traditional soffit material!

There is no reason to replace the bottom length of shiplap as the frame is protected by the membrane and DPC, and the gap between the back of the cladding and the frame allows air to circulate betwwen the laths and dry off any moisture

 

[mpooley]

Thanks Woody

 

[JohnD]

A good thing about shiplap is that it's horizontal, so when you're building the shed you can cut a few extra pieces to fit the bottom one or two pieces and tuck them away (I put mine behind the cladding) for future replacement. The bottoms are most likely to be damp and so suffer from rot and woodlice.

You can also give the bottom one or two pieces lots of extra coats of cuprinol preservative, and, when dry, whatever water-repellent stain or oil you are using on all surfaces.

Setting then to throw off rain so they aren't standing in puddles will be a tremendous help. You can kick out the bottom one a bit to help.

 

[^woody^]

With any timber frame, the frame should be on top of 2 courses of [engineering] bricks and at least 150m above ground level. Same for the cladding

The frame and the cladding will never then be constantly wet and so should not prematurely rot.