drying larch cladding

[Trigs]

hi,
I'm about to build a new workshop and clad it with Scottish Larch, question is i believe the timber isn't kiln dried and maybe fresh sawn. Should i air dry before fitting or pre drill nail holes to prevent splitting. If i need to air dry how long roughly would it take to dry an a garage?

cheers

 

[dickm]

You don't want kiln dried for cladding anyway - it will just re-wet to equilibrium with ambient air (which at the moment in Aberdeenshire is fully saturated!). If it's fresh sawn, I would be inclined to let it air dry if possible before fixing in place, unless your fixings will allow for significant shrinkage without splitting the wood (which would be good practice anyway).
If these are just rough sawn planks for vertical cladding, which is how my house and workshop are done, then one tip I learned the hard way is to lay the planks relative to the fixings so that the likely direction of cupping will if possible tend to close up any gaps. Some of the boarding on the house is laid with the curve of the growth rings such that any radial shrinkage tends to open up some small gaps in summer. Though no problems this year!
Depending where you are in Aberdeenshire (I'm in Methlick) if you wanted to have a look at the way our place is done, PM me.

Out of interest, where are you getting your larch? Son-in-law wants some for cladding, and we've not had a lot of success in sourcing so far.

 

[Phil Pascoe]

Your house is done in vertical cladding? I've never seen a house done in vertical - horizontal, yes.

 

[dickm]

Yup, vertical, rough-sawn Swedish pine of some sort on the original house, larch with similar orientation on the small extension. Butinox every 7 years and seems fine. Actually, vertical cladding (but usually with planed timber) is pretty common up here in the wilds.

 

[heimlaga]

This is a good way of drying wood:

Just remember to tie down the roof tin a bit better. This isn't windy Aberdeenshire. I got the tin for free from some demolition sites.

 

[Trigs]

Cheers guys, Dickm I live in peterhead and got the cladding form Gordon sawmill in longside. Originally I was going to go with Russwood, ( if you look at the Formartine building near Tarves the cladding on there is from Russwood) but the price for what I wanted from them blew my budget away even though it looks very nice. The boards I have are 150x16mm looks fresh sawn and rustic lets say, but as it's the splits and twists I want to avoid as much as possible. I also got hold of a moisture metre and looks to be around 25% -30%.

 

[dickm]

Didn't know where John had sourced the wood for Formartines, so that's interesting. The whole story of that building is fascinating - not sure which of us is more energy efficient, Form's or our house!
Sounds like your larch could do with a spell air drying before you use it - could you leave it with air circulation out of the sun for a vew months?

 

[Alan Smith]

As I grow and mill a fair bit of larch, Sussex not Aberdeenshire although I am an Aberdonian, I thought I'd chip in with some observations. Don't be tempted to use the larch too wet, if you can even get 6 months drying in shade and under an open cover it will make a big difference. Also larch is a bugger to nail and would recommend predrill for nails especially cladding thickness. If you don't drill it will split, if not when you nail a day or so later. Pay attention to ring orientation if the stuff has come from big logs you might have less of an issue but from smaller logs try to anticipate which way cupping will occur.

 

[Trigs]

the building is up and nearly ready for cladding, just doors and windows to fit tomorrow. I have the boards stacked up inside, I'll hold off on the cladding though for a month to 6 weeks but it'll need to go up then as I'll be working from it. Heres a pic as it is now. Once its finished I'll put up the full thing. I'll nail it as in the diagram on the left with a 25mm overlap.