Disused Chimney. Can I insulate it?

[stem]

I have a disused chimney in my dining room. Originally it had a cowl on the top and an airbrick at the base for ventilation. A few years ago, I took the chimney down below the roof line into the loft, and extended the roof over it. (The flashing needed replacing and I also wanted a few bricks for repairs elsewhere.)

I would now like to brick up the air vent at the bottom and fill the entire chimney with loose fill insulation. My thinking now, is that it is more akin to a cavity wall, than a chimney.

A drawing below shows the general layout. Does anyone see any problems with this?

Untitled

• stem
• 6 Nov 2012
• 1

 

[theoldun]

As on one has answered your question for you, we will.

No problem with what you propose, providing top of flue is below roof line. As you say, it is a cavity within a cavity. Suggest Micafil. You require enough for approx 0.35m3 so 4 bags should do you.
Regards oldun