Filling in around flue

[jakefouro]

Hi all,

I am installing a solid fuel stove in my conservatory and because I do not have a chimney, I will be knocking a hole through the cavity wall (twin 4" block) and putting in a double walled insulated flue. The flue will be exiting the stove at the rear and going through the wall at a 45 degree angle. My queries are as follows:
1. What is the best way to fill in around the flue once in place. The existing wall is finished with a smooth sand/cement plaster finish on the external wall.
2. Do I need to take precautions to stop moisture gaining entry along the smooth wall of the flue?

Thanks in advance for any advice.

 

[noseall]

make good using sand/cement mortar, filling all voids.

once rendered back up, you should be watertight.

 

[jakefouro]

Thanks noseall, no need to take extra measures then to stop moisture ingress along the flue?

 

[Roadyz]

Thanks noseall, no need to take extra measures then to stop moisture ingress along the flue?

is this question because its coming out at a 45deg angle? ie water sittingon the top edge of the flue against the wall ? if so cant you seal the void with silicon or somthing? before cementing?is there a reg for this?

 

[jakefouro]

Thanks guys - I'll go with some silicone where the flue meets the new plaster on external wall.

 

[tryitandsee]

So near to the source of heat may cause s&c to crack with the flue expanding and contracting.

Have you thought of using 'fire rope' and packing that around flue where it exits wall. Then fill with fire cement (comes in cartridges now) smoothed over.

 

[jakefouro]

The s + c should be ok, tryitandsee as the flue is insulated but the fire cement is an option - I will check to see if it can be painted over.