Wood cladding – dimensions and sourcing advice

I’ve a 6′ retaining wall at the back of my house.
The decorative facing bricks in one area had been blown out by the frost. We have removed them.
I plan to replace with board and batten cladding like this, but it will be panted.

I’ve a local garden centre that can sell me pressure treated fencing wood – it’s dafty cheap 19mm X 150mm boards and 75mm X 32mm battens. But it is fencing timber – I’ve had to be fussy about warped boards in the rest of the garden. The dimensions also seem designed for fencing, not cladding (duh!)

Is this a step too cheap?
If so, where to get 12m2-14m2 of cladding from – and what dimensions?

Get on Facebook marketplace Matt, I get timber from a guy locally who does reclaimed wood, cheap and loads of life left in it, and it feels good reusing something that may otherwise be binned.

Or put a wanted ad in for scaffold boards, usually some kicking about and they’re generally solid.

I would probably go for the back boards as 150mm x 19 or 22mm and the front battens 50mm x 19 or 22mm. This will give approximately 120mm back board showing, allowing for a 10mm gap between the boards.

Allow for ventilation between your boards and the brick wall, to help longevity of both, you could install a Tyvek type breathable membrane on the battens.

As for what timber to use, if you go for cheaper softwood, then it’ll be tanalised or pressure treated, which is fine but it’s generally fast growth stuff and will need regular maintenance/painting.

How about Douglas Fir, Larch or Western Red Cedar? You may find a local sawmill with some and these varieties can be left as they are and will silver off as they age. Their natural resins make them very resilient. Alternatively, a something a little more left field could be green Sweet Chestnut.

Ideally, the wider boards want to be quarter or rift sawn, although that tends to be expensive due to waste, so just make sure you lay the boards with the heart outward facing, I.e. the growth rings are convex to the wall.
HTH

As for what timber to use, if you go for cheaper softwood, then it’ll be tanalised or pressure treated, which is fine but it’s generally fast growth stuff and will need regular maintenance/painting.

Although vendors don’t usually state it there’s different grades of treated wood. Prices / grades vary depending on how dry the wood was when treated which gives different levels of penetration by the treatment. It can mean you’re not really comparing like with like on prices between suppliers.

I get timber from a guy locally who does reclaimed wood,

Oooooo. Who? Who?

hargreaves reclaimed flooring isn’t too far from the op and they had big piles of exterior timbers as well as the more precious stuff last time I was there

I’m up for reclaimed or local sourced, I’m also up for sweet chestnut etc – but the cost has to be kept down.