Chimney, no flaunching.

[liftfan]

Hello,

I have a woodburner off one pot and I’d like to put another one in off the second pot (they lead to ground and first floor levels).

The second pot has a ventilated cap on it (I’ve removed it in the picture) but when it rains there is a slight drip down to the open fireplace. I can see the mortar needs repointing around the pot.

There is no flaunching on top. Should I just add it? However, the pots are only 3 inches off the brickwork and I need to add the cowl for the flue like the existing which won’t give me much space for flaunching.

Any advice?

Thanks

 

[Burnerman]

A flaunching was traditionally needed to retain the clay chimney pots as well as cast water away but in your situation all seems to be fine without it....just keep the pointing in good nick.
John

 

[liftfan]

Great thanks!

Any harm is putting some Thompsons water seal on it?

 

[Burnerman]

No harm at all but maybe a couple of coats of Evercryl or similar would be better if you want to minimise water absorption.
John

 

[catlad]

Best thing you can do for your chimney is use it.

 

[lostinthelight]

If this is a crack then it will need some remedial action or water will run down the flue.

 

[liftfan]

Yes, it’s a hairline crack. What’s the best way to fix it?

 

[Burnerman]

I'd not be inclined to mess with it too much, but agreed you don't want water in the crack in case it freezes and bursts.....consider a cover of Flashband to make it water tight, and the jubilee clip for the new cowl will help keep it there.
John

 

[lostinthelight]

I wouldnt mind betting the crack extends further down the liner so any water seeping through the top or upper perp joints can still get in.

 

[liftfan]

Thanks for the advice all. I’ve got some Evercryl and flashband ready to go. I’ve done a temporary splodge of Black Jack repair mastic over a few dodgy areas of mortar and despite some heavy rain there’s now no leak.

An additional question though. At the moment both chimneys “pots” are at the same level. The new wood burner will be on the floor below the existing. I was chatting to someone a while back who suggested I might need to add a 500mm high pot on top for the new flue. Any thoughts on this?

Thanks.

 

[datarebal]

last thing you want to do trap any moisture inside the stack..

 

[bobasd]

wood burning solid fuel shows on the right hand flue - there are signs of heavy creosote sticking.
creosote in the flue creates a big risk for chimney fire.
the flue needs sweeping with wire flails or even with chains - but the sweep must be well qualified or experienced in using these devices.

 

[liftfan]

Ok, thanks about the creosote warning. It’s not something I’d considered before. Googling I see you can get powder you put on the fire that can break down the creosote. Are these any good?

About extending the chimney pot, it may have been something to do with stopping smoke returning down the other flue. Although as it stands the new flue will be around 8m long and the flue to the existing woodburner is around 5.5m.

 

[Burnerman]

These creosote removing compounds do work to some degree, but its best to use them all the time......one dose wont clear the chimney but eventually the creosote turns to a cinder which breaks off in lumps.
Its only successful if the fire burns hot, and that is the formula for wood burning flues - dont close the dampers on the stove when burning wood as it doesnt like to smoulder.....allow the fire to burn well.
As for raising the chimney, no one can tell if it will work but personally I dont think there will be an issue if you dont live in a downdraught area. All you can do is to give it a go.
I get my chimney sweeping gear from fluesystems.com and now use the thin ultra flex rods that they make.
Absolutely brilliant gear for lined flues especially.
John

 

[bobasd]

creosote must be regularly removed by some form of sweeping - its a must.
if your house is insured - do the insurers know about your woodburner?