Thermowood Ayous or Ash

[flanagaj]

I am looking for a cladding option that I can hopefully fit and forget.  My current thought is to use a thermowood cladding.  I have had samples of Poplar, Ayous and Ash delivered, but they are all a very dark brown colour due to the thermo process.  The Ash is far denser than both the Ayous and Poplar and the price reflects that too.

 

What I want to understand is how these timbers age with time and whether anyone has used thermowood on their house.  If so, please share a photo as I'm keen to see the colour of the wood after being exposed to the elements for months / years

[nod]

I used a woodgrain cement board on three plots about ten years ago 

Still looks like the day it was fine 

Easy to cut with a guillotine 

[Russell griffiths]

Vastern sawmill has a huge display of every type of timber they do on display outside. 
TBH  they all look identical from 10 m away

they have all weathered to a really dark colour. 
so I’m unsure if changing type actually makes any difference after it’s been sitting outside for a couple of years. 

[saveasteading]

I have found that, by applying 'light oak' stain to softwood cladding, it remains much the same colour, perhaps a bit yellower.

It goes on as barely visible so seems expensive at the time but the benefit is over the years as it does not grey.

Either apply before fixing or allow shrinkage first, as tongues or edges may show when they grey.

[Nick Laslett]

@flanagaj, we have Thermowood Ash from QTD. 
 

https://www.qtdgroup.com/cladding
 

This material will lose all its colour and go grey just like normal timber cladding. 

 

The advantages of the Thermowood vs normal timber are:

1. Dimensional stability 

2. Greater resistance to insects and fungi. 
 

That is it. 

Downsides:

1. Cost

2. Installation time. Thermowood needs pilot holes and is fixed with screws. You can’t use nails,  the timber is very dry and splits easily. 
 

If you use timber paint on thermowood, it will last a lot longer as the thermowood does not expand and contract as much as traditional cladding, so the paint doesn’t crack as easily. 
 

We used Osmo Clear UV oil for first year, but that stuff only lasted a year before needing a re-coat. Considering OSMO tinted UV oil this year. Or going with a paint. 

This has also been recommended. 
 

https://rubiomonocoat.co.uk/durogrit

Picture of when it was first installed. I will post a more recent one later. 
 

 

Edited 11 hours ago by Nick Laslett

[Russell griffiths]

I nailed all my thermo modified poplar, it’s inside on a ceiling so isn’t catching the weather. 
secret nailed through the tongue. 
this method may not be substantial enough for outside use.