Would Polyfilla do for this?

[Profpointy]

Put new brackets up whilst the pipe is in situ then.Cant speak for sweepee but it's not a massive job.Id want it right.

That's what I'd do too. Get new brackets and suitable bolts / screws and start again. Likely easier than trying to make do. I'd not want to "pull" the pipe particularly, as that seems wrong to me. It should naturally be straight with the bolts just to keep it there.

 

[GuyBoden]

If it was my boiler extraction pipe and it came loose again, I'd take them long extension pipes off and stick the end cap on the first bit of pipe coming out of the wall.

The pipe is ridiculously long due to new regulations for fume extraction near your external vent.

 

[CXRAndy]

Can't believe how shoddy, some tradesmen are. Jesus I could do a far better job. Just spend a little time getting the correct fittings and that would never happen.

If that is a vent stack , it should either reach up and extend beyond the gutter or fit an air admittance valve to the shorter pipe. There is window, likely to a bedroom

 

[slowmotion]

I would get a cartridge of polyester resin from screwfix.

https://www.screwfix.com/p/rawlplug-r-kem-ii-styrene-free-polyester-resin-300ml/32863

 

[Mr Celine]

I didn't really want to (and get them into trouble with BOXT) if it could be a quick 'n easy DIY job. I'm a bodger...but quite a nice bodger.

If that's the boiler flue get them back. It shouldn't be up to you to fix their bodge and if anything goes wrong with your bodge who would be liable?

 

[Adam4868]

He's done it....and is happy 😁
He's coming round mine later in the week to finish my bodge jobs....

 

[swee'pea99]

Also, while it's dry weather put something to seal the fascia of the brick that's come away by being drilled, you don't want the rest of the bricks fascia to blow over time/weather, the bits that have chipped away around the edge of the drill holes

Thanks, that wouldn't have occurred to me. I'll do it!

Must confess I'm tempted by the 'just remove the damn silly pipe' option, but for the moment it no longer appears to be broke so...