Help choosing wood for exterior of workshop

[DigitalM]

I'm setting up a workshop with my brother-in-law (here after referred to as BIL), in an outbuilding on his land. It's 7m x 3m, and is currently clad with what I assume is ship-lapped ash. Whatever it is, it's grey and knotty. Frankly, it looks a bit battered, although to me that gives it some charm. BIL however, wants to spruce it up (no pun intended), and maybe even paint it. Well, it's his building, so...

I could use some advice on what to use to re-clad the thing as I'm not big on woods for exterior use, in fact, I'm totally rubbish.

Anyway, if anyone has time to help me get our workshop plans a little nearer to reality, I'd be really grateful for advice on the following:

What to use if keeping it natural looking
What to use if it's going to be painted

I'm not paying, and BIL doesn't mind shelling out a bit more for quality if it makes a meaningful difference.

Also, we're between Bristol and Gloucester, if there are places that have a lot of choice for this sort of thing I'd love hear about that too.

 

[DigitalM]

Got that wrong, the current construction is square edge clad.

 

[Phil Pascoe]

It wouldn't be ash - it's not durable (and expensive for that use). Probably larch if it's knotty.One of the coloured fence treatments is probably the cheapest and easiest. Sadolin or Sikkens is better but much more expensive. Or of course if you don't mind the smell, creosote.

 

[WellsWood]

I think you may be putting the cart before the horse somewhat here - in that if this is going to be a working environment the priority should be whether the cladding, and indeed the walls themselves, is doing its job of keeping out the elements (and likely to continue doing so) rather than its appearance. You don't say whether the workshop is for pleasure or business, or what the current structure consists of. If you went down the re-cladding route there is the opportunity to upgrade the walls with breather membrane and insulation etc., if it's not already there, which could make a major difference to the comfort level inside. Not to mention significantly improving the lifespan of tools and machinery.

I would say put money into refinishing the exterior only if the wall structure is sound and suitable to purpose first.

 

[DigitalM]

Thanks for the replies, I wasn't sure how much detail to go into but I'm very happy to expand.

EXTERNAL:
Current construction is a 3x2 frame with square edge clad of "probably-larch".

BARRIER:
Behind that was a clear membrane made of "probably-poly-something-or-other", that has seen better days due to ingress by "some-shrub-or-other". This probably needs replacing too, and you're right, now would be the time to do it.

INSULATION:
The 3x2 frame was packed with polystyrene blocks that had started to perish, especially in those areas suffering from shrub-ingress, leaving tons of little white bits everywhere. This has all been ripped out and tipped.

INTERNAL:
The interior was clad with a really horrible grade of chipboard. It had swelled a little and stained in places due to water ingress. It looked bad enough that we simply ripped it out.

FLOOR:
The concrete floor, which was fairly soft and the surface of which could litterally be brushed off, over and over, was replaced with a resin floor, because we have a mate in the trade.

So basically, we currently have the frame, roof, membrane and cladding.

Anyway, so pleased to be able to discuss this and get my head around it a bit more before I end up standing in front of some sales assistant!

 

[NickN]

I used this stuff for exterior:

https://www.edecks.co.uk/m/products/572 ... mm-x-120mm)

Which can be creosoted or stained ok, not painted though.

And under it you want breather membrane, like:

http://www.cromarbuildingproducts.com/i ... c-breather

 

[DigitalM]

I used this stuff for exterior:

https://www.edecks.co.uk/m/products/572 ... mm-x-120mm)

Were you pleased with this stuff?

I used this stuff for exterior:

And under it you want breather membrane, like:

http://www.cromarbuildingproducts.com/i ... c-breather

Thanks for this, I was also looking at Web UV 15.

 

[RobinBHM]

If you want new cladding to really last and want to achieve a dry sealed interior, I would remove the cladding, fit a breathable membrane to the studwrok. then fit 50 x 25 tile battens laid flat vertically, then fit the new cladding to that.

The advantage is that the breathable membrane seals the interior from rain water ingress, the tile battens create a small 25mm cavity that allows the cladding to breathe and allow any rain water that penetrates to escape, increasing the lifespan of the cladding.

Cromar breatheable membrane will work, tyvek housewrap is probably the best. Tape the joints using the correct tape.

If you really want to go to town, you could run some damp proof membrane just below the bottom framework just before fitting the breatheable membrane, that will then create a durable drip edge for any water that gets into the cavity.

before fitting the vertical battens clip some plastic insect mesh around the bottom, fit the vertical battens, then turn the mesh up and over to close off the bottom. It stops wasps etc getting in.

If you are replacing the cladding, then upgrading to this is not much and well worth doing.

If you want to insulate, then celetex can be put on over the framework first, If you tape the joints you wont need a breathable membrane, just screw the battens over the top.

Cladding, anything from treated softwood feathedge which will last a long time if done as above, to green oak, siberian larch, cedar etc.

 

[NickN]

I used this stuff for exterior:

https://www.edecks.co.uk/m/products/572 ... mm-x-120mm)

Were you pleased with this stuff?

Yes - I didn't buy it from the site I listed, but a local independent builder's merchants - same stuff and it fits together nicely. Once creosoted (not that you can buy anything like that, of course.. *cough*) it is about as good as you can expect a wooden cladding to be without spending much bigger money on something like log lap.

 

[DigitalM]

Does anyone know of something like celotex/kingspan that's not one of these big brand names but is more competitively priced.

The studwork would hold 70mm thick insulation, but that would be £1200 at Wickes (a bit less if ordered online). Even knocking that down to 30mm and buying online it's £400.

It was polystyrene before and it perished quickly and just found it way everywhere. I'm not sure about rockwool - I found a few references to people saying they'd used it in outbuildings before and wouldn't again.

 

[skipdiver]

£1200 seems a hell of a lot for a 7m x 3m workshop. Wickes is not the best place to price up Kingspan. If you shop around, you should be able to get it for £25 a sheet. Even 50mm Kingspan/Celotex will give more warmth than Rockwool i'd have thought.