Jump to content

Insulation behind woodburner


nwnw

Recommended Posts

I'm changing out a wood burner and I want to insulate to the stone wall behind while I have access. I only have about 60-70mm from wall to flue. 

Can anyone advise on best fire board and insulation combo to give best insulation? Is aerogel fit for this purpose? Only 1m2 so cost is not an issue. 

Edited by nwnw
Link to comment
Share on other sites

  • 4 weeks later...

Lost the thread on this when xmas took over.

Does anyone know if Spacetherm (aerogel blanket) is suitable for this purpose?  By the specs it looks ok for temperature and is fire rated.

 

Link to comment
Share on other sites

On 19/12/2023 at 00:49, Iceverge said:

When the stove is up to temp its thermal conductivity will only be the same as PIR . If you could sub 15mm of rockwool you'd be in the same place. 

 

Is it a twinwall flue?

This doesn't make sense to me.  The U-value of aerogel blanket far exceeds that of rockwool.

Link to comment
Share on other sites

On 12/01/2024 at 15:54, nwnw said:

This doesn't make sense to me.  The U-value of aerogel blanket far exceeds that of rockwool.

 

image.png.6a2c62da299ea1b1140703bd47181242.png

 

 

Sorry I was a bit off with my calcs. 

 

10mm of a thermal conductivity of 0.0195W/mK will give a U value of 1.95W/m2K. for £150.

 

18mm of Rockwool with a thermal conductivity of 0.035W/mK will also give you a U value of 1.95W/m2K. 

 

You can't buy 18mm though so if you can fit 25mm of rockwool it'll be a U Value of 1.4W/m2K for a cost of £3. 

 

 

 

 

 

 

  • Thanks 1
Link to comment
Share on other sites

Yes, Iceverge you are spot on.  I should have dug into the numbers.  I thought aerogel was supposed to be some wonder material but once manufactured into the blanket form a K value of 0.02 vs 0.034 is Rockwool is not exactly groundbreaking.  I now see why aerogel has not taken off!  Thanks.

  • Like 1
Link to comment
Share on other sites

You can go for Promat Promafour board but they are very expensive as they are designed for fireplaces and wood burning stoves.

Also using a promat you need to use their filler, glue and it would cost a fortune.

 

image.png.fe23f7db4dc944beab8f7e527cc7c737.png

 

Personally, I would go for a cheaper option using rockwool ablative coated batt combined with 6mm a1 multipurpose board.

I got it installed 10 years ago and it works well, the board behind the stove is covered with black fire paint.

See below:

image.thumb.jpeg.5f944534cd98914f85e3f917bc2630a0.jpeg

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...