Accoya doors\windows

Soldato
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Has anyone used Accoya in preference to hardwoods for timber doors\windows?

We're having some bespoke french doors made up - Accoya (treated softwood) is being pushed as the current go-to material. Guaranteed for 50years for above ground use, and highly dimensionally stable. Even the exterior paint is guaranteed for 12 years.

Any experiences, good or bad?
 
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We are just treating tongue and groove softwood for cladding right on the coast. The reports are good and most of Europe are happy with softwood windows so any treatment like accoya can only be good.

The only question I would have would be if you're having a clear varnish or oil after if the sections are one piece or finger jointed and how many per meter.

My composite windows are all one piece however last time I spoke to the supplier they had gone to finger jointed every 300mm which in my eyes isn't very nice for good quality windows. Doesn't matter if they are painted though.
 
We are just treating tongue and groove softwood for cladding right on the coast. The reports are good and most of Europe are happy with softwood windows so any treatment like accoya can only be good.

The only question I would have would be if you're having a clear varnish or oil after if the sections are one piece or finger jointed and how many per meter.

My composite windows are all one piece however last time I spoke to the supplier they had gone to finger jointed every 300mm which in my eyes isn't very nice for good quality windows. Doesn't matter if they are painted though.

Same price as Hardwoods such as Sapele, and Oak, which appear to be the common alternatives. More dimensionally stable, and longer guarantee however. ~2.8K fitted in our case (large doors, bespoke size, 1.1u glazing).

Spay painted opaque colour, 2x coats 240 microns per coat. The raw material looks OK, but would probably go with a traditional hardwood if I didn't need to paint it to match rest of house.

Only issue appears to be the hardware used, think they have to go for alu, or triple coated products due to the preservative. Seem to have this sorted now.

There are finger joints, unsure of quantity per meter. Assured that the finger jointing is at least as strong as core material, and that the timber is certified for structural use. I know some architects are using it structurally now. Ran my hand over a raw jointed piece and you cannot feel it. Painted, it'll be fine.
 
Accoya is available in standard sawn sizes, I would avoid laminated stock even in Accoya. I haven't found anything negative to say about the stuff, though it is sensitive to certain adhesives and paint systems.
 
Same price as Hardwoods such as Sapele, and Oak, which appear to be the common alternatives. More dimensionally stable, and longer guarantee however. ~2.8K fitted in our case (large doors, bespoke size, 1.1u glazing).

Seems reasonable, given the requirements.
I don't know if I've misunderstood something but a u-value of 1.1 seems high, well not 'high' exactly just higher than I would assume for a modern glazed door. Perhaps thats just due to the size of the glazing?

There are finger joints, unsure of quantity per meter. Assured that the finger jointing is at least as strong as core material, and that the timber is certified for structural use. I know some architects are using it structurally now. Ran my hand over a raw jointed piece and you cannot feel it. Painted, it'll be fine.

So have you got these made up by a joiner? I'm just thinking out loud but could one buy the wood and ask some to make the windows/doors up for them and and avoid any possible issue with finger joints?
 
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The reason they recommend laminated sections is to save money on materials.

Any decent wood worker knows how to pick a suitable piece of timber for a component. If a piece of timber in a laminated section has stresses or is unstable it can quite easily break the glue joint. I run a small joinery business and for the above reasons never use laminated sections unless I manufacture them. I would recommend specifying solid sections if you have the budget.
 
Seems reasonable, given the requirements.
I don't know if I've misunderstood something but a u-value of 1.1 seems high, well not 'high' exactly just higher than I would assume for a modern glazed door. Perhaps thats just due to the size of the glazing?



So have you got these made up by a joiner? I'm just thinking out loud but could one buy the wood and ask some to make the windows/doors up for them and and avoid any possible issue with finger joints?

1.1 high? My understanding is that it's a measure of watts lost per sqm, so the size is not relevant. Best available is 1.0 I believe (which I may still plump for), and building control stipulate 1.8 or below. Think we're good :).

Yes, made by a joiner. Will enquirer about finger-jointing with surveyor.
 
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