Hole around flue on inside wall needs repairing.

[Yannis.sp]

Hello,

Due to recent storm I went into the boiler cupboard to see why so much wind was coming through.

I found a disastrous hole where the flue goes out. See photos. ( Haven't lived here that long, boiler was already in place, it's a modern valliant ecotec 24 condensing but not entirely sure)

The flue goes out over my bathroom for 2,5-3 meter (plasterboard ceiling) and out to the outside wall (there is a gasket and a cowl to the outside seems sealed)

I want to repair this hole and stop wind coming through.

Is it something I am allowed to do or does it require a gas safety registered engineer?

I thought to use some sand cement after googling around but I wanna know if it's safe/acceptable to be done by me.

Would a "flange" with fire rated plasterboard be acceptable?

Does the mortar go close to the flue or do I leave a 3-4mm gap and seal with fire rated caulk?

Thanks for reading.

 

[CBW]

Hello Yannis,

Sand and cement in that hole will probably fall through. I would patch the hole using some thermalite block and sand and cement and then finish with sand and cement. As long as you’re not disturbing the flue, you should be ok. Also check it’s screwed up the other side of the clamp bracket.

 

[Yannis.sp]

Thank you for your kind answer. I have some thermalite, I can prop it up by some wire to come forward and used as a mold for the mortar. I can build the mortar in 3 goes so it doesn't fall down.

 

[Madrab]

Careful .... before you go filling that up, if it's over 2.5 meter then that flue may have a joint in it, if that's the case then access will need to be made so the joint can be inspected periodically (when serviced)

 

[Yannis.sp]

Careful .... before you go filling that up, if it's over 2.5 meter then that flue may have a joint in it, if that's the case then access will need to be made so the joint can be inspected periodically (when serviced)

Thank you Madrab, there is a plastic inspection hatch 20x30 in the bathroom ceiling, under where the flue runs. That would have been put in there for inspection I would imagine?

 

[Madrab]

Good stuff, as long as there is an inspection hatch and you can see the joint when it's open, then fill away. I usually pack the gap with B&Q's recycled insulation and leave enough of a gap to take some mortar, makes it easier to remove for the next time.