Alternatives to Siberian Larch….

[G and J]

So, we put in our planning permission with our design substantially covered in vertical Siberian larch cladding.

 

Separately to this, I read a lot about the war in Ukraine, and I’m very aware of the embargo on Russian products.

 

So why I did not put the two together? Perhaps I assumed that Siberian Larch was a species grown in many places not simply larch from Siberia. Please don’t answer the “question how dumb is that?”.

 

So we are now seeking alternatives. We have to have a fire treatment because we are within a metre of the boundary . We are committed from an ascetic point of view to vertical cladding, preferably 100 to 140 mm wide, and we want something that never needs to be treated because one of our goals is a low maintenance house.

 

We are being directed by several companies towards a product called Ayous. Has anyone on here used that already? Does anybody know anything about its longevity other than the sales staff I’m talking to?  Are there any other alternatives we should be seriously looking at?

 

As always help gratefully received. 

[Mr Punter]

How about fibre cement planks, like Cedral or Hardie?  I prefer the smooth finish.  They need little maintenance and the finish is long lasting because the planks don't expand like timber.  Also they are fire resistant.

 

If you are thinking of fire treated timber you may need to have them pressure treated with Non Com, not just coated.  Very expensive.

[G and J]

Ah yes, thanks..... should have said we do want actual wood, which will have to be factory fire treated and therefore the sioox coating (which we like) is not effective.

 

Also should have said the ayous would be thermally treated.

 

Plan is just to let the wood go silver, so knot holes etc (half rendered) is not the look we were hoping for.

[Roundtuit]

Russwood do a factory treated fire retardant/ Sioo-X combination that might be worth a look, and maybe something like their Scotlarch or Thermopine?

[saveasteading]

1 hour ago, G and J said:

have to be factory fire treated

Are you sure of that?

The aim is that a fire next door doesn't set your wall alight, so a surface treatment should do. Perhaps some closure to any cavity as well.

 

3 hours ago, G and J said:

a product called Ayous

Had never heard of this It appears to be a exotic, rainforest type timber, with ayous being one of many names.

 

I have used 'larch' otherwise unspecified on many hundreds of m2. I get  it tanalised and then prefer to colour it but that is opinion.

 

Russwood is beautiful, but is  priced accordingly.

 

[Tosh]

I had some samples of Ayous, thermally modified, and liked the look of it but wow is it brittle and it also marked very easily. The grain pattern didn't really suit the look we were after in the end but that's a personal thing. It was a reasonbale price circa £6.50/lm if I recall. We ended up going for cladding from Norclad. Its A+ GRADE Brunnea treated Redwood, very few knots. And as its treated it's not as brittle as some of the thermally modified stuff. I'm sure there's some info on Norclad site about additional fire treatment as well. Note Norclad are part of Arnold Laver now who are in turn under the National Timber Group. The reason I mention this is if you wanted to use Norclad then your BM may have accounts with AL and/or NTG so you might be able to negotiate a better deal.

[Kelvin]

2 hours ago, Roundtuit said:

Russwood do a factory treated fire retardant/ Sioo-X combination that might be worth a look, and maybe something like their Scotlarch or Thermopine?

Russwood are expensive but we went with them. Scottish Larch treated with SiOO:X but not treated with fire retardant. We couldn’t be happier with it but it is very rustic. You can see the planer marks on it albeit it’s very uniform and adds a lot of character especially at night when the lights illuminating it. It’s very knotty but we also love that. Russwood also had a quantity of Siberian Larch left in stock. This was a year ago so likely gone now. 
 

You also need to factor in intumescent cavity barriers that allow air to circulate behind the cladding but then fill the cavity if there’s a fire. These are not cheap especially for vertical cladding as the void is typically deeper. I have a quantity left over. 

Edited July 25 by Kelvin

[JohnMo]

Home grown Scottish Larch. Keep the travel miles down.

[Kelvin]

3 hours ago, G and J said:

 

 

Plan is just to let the wood go silver, so knot holes etc (half rendered) is not the look we were hoping for.

Be mindful that if left to go silver naturally it won’t be uniform. It’ll mostly retain the orange stain under the windows and eaves. The silvering is beautiful, ours looks like golden driftwood. It’s also completely uniform top to bottom and on every elevation. Untreated larch left to silver naturally can look pretty awful quite quickly. 

[Mr Punter]

If you are looking at a home grown timber, Sweet Chestnut is worth considering.

[ToughButterCup]

1 hour ago, Mr Punter said:

... Sweet Chestnut is worth considering.

 

It's finding it that's the question. I tried hard to get some but could only get one trees worth. And that was from a public park in Liverpool. It's beautiful wood though.

[saveasteading]

43 minutes ago, ToughButterCup said:

It's beautiful wood though.

It greys the same as softwoods. I haven't ever seen any architect's' photos of it in faded grey, with nail streaks, always in newly built gold.

[Mr Punter]

1 hour ago, ToughButterCup said:

 

It's finding it that's the question. I tried hard to get some but could only get one trees worth. And that was from a public park in Liverpool. It's beautiful wood though.

 Beechwood Hall in Cooksbridge is clad using Sweet Chestnut.

 

https://www.facebook.com/photo.php?fbid=871128391694956&set=pb.100063934084990.-2207520000&type=3

[saveasteading]

this is how it is usually advertised.

 

[ToughButterCup]

12 hours ago, saveasteading said:

... in faded grey, with nail streaks, always in newly built gold.

 

Beautiful image. We used stainless steel screws - increased the cost of our cladding mostly paid in the extra time it takes. 

[saveasteading]

2 hours ago, ToughButterCup said:

our cladding

Picture?

[ToughButterCup]

[G and J]

On 25/07/2024 at 15:58, Kelvin said:

The silvering is beautiful, ours looks like golden driftwood. It’s also completely uniform top to bottom and on every elevation. Untreated larch left to silver naturally can look pretty awful quite quickly. 

Would you be happy to post a picture? And am I right in  thinking you used thermopine on your deck.....a picture of that too would be fantastic.........

 

We are really impressed with Russwood and its an important element of the build for us only snag is they only offer either scottish larch in b on b (we weren't originally thinking of that profile) or thermopine with both the burnblock and sioox treatments.....ta

[HerbJ]

We used Sweet Chestnut for our build in 2015/16.

There was post on the subject on April 2022 - see attached.

I can take some current photos, if useful?

 

 

[G and J]

Thanks  @HerbJ that' kind. The problem we have is finding something that can take both the fire treatment and the coating that accelerate and even out weathering to silver.

[oksleator]

I love charred timber, Shou Sugi Ban style, I think you can use various different timbers for that, and it's already burnt so resistant to further burning? 

[G and J]

5 minutes ago, oksleator said:

Shou Sugi Ban style

It looks good, but we are in a an area(residential) that was up in arms about cladding, even though the silvered timber will be in keeping with the boat yards in the conservation area about 500 yards away......our planner was supportive, the neighbours not so much....

[oksleator]

Ugh frustrating. We've had the opposite on our street. Neighbour has a big extension being built and she wanted charred wood, we (neighbours) were all excited to see it. Planning said it's not in keeping so she's had to go the Ayous route, which definitely wont fit with our yorkstone mill cottages. It's not clad yet or I'd take a photo for you.

[saveasteading]

1 hour ago, G and J said:

something that can take both the fire treatment and the coating that accelerate and even out weathering to silver.

Perhaps discuss with the building inspector. If the chance of your wall catching alight is very low, for example because there is little chance of the neighbours having a bonfire, or their house is brick, or there is a pond adjacent, then does a year matter?

Let it go grey   elegantly silver,  and then paint in intumescent.

Risk is time related, so for year one you could be ultra-careful to avoid any fires adjacent.

[G and J]

Unfortunately we are cheek by jowl (1m one side/ 1.5m the otherside) between 2 1920s timber framed properties....BC won't wear it.