New fireplace + gas fire problem

[Why do precast flues cause you so many problems Anjme? ]

They were not designed, 40 years ago, with inset fires in mind.
Often the walls are plastered directly over the concrete flue blocks causing cracking in the wall.
The flue block depth is often very shallow, it does not always start at floor level which is required for most inset installations.
The builders often "forgot" to clean off the excess cement from inside the blocks as they were placed upon each other causing cement to ooze out inside the new flue and form cement obstructions.
Its not very often we see a flue in the loft as you describe, more often there is a pipe, usually old asbestos, cemented into the blocks in the loft and then exiting out through the roof. This is often the wrong size, the joints are damaged or there are tight bends in the system which obviously restricts the flue pull.

These are but a few problems we come across.
We always carry out a full flue inspection and loft inspection without fail on these old precast flues.

Good luck with sorting it out. I am in Leeds myself if you get really stuck, look up my profile. ( not allowed to post my web addy)

Cheers for the advice anjme

I've got another Corgi registered plumber coming round on the weekend. He's gonna check the chimney properly + check for spillage etc...........so we'll see what he says. What type of remedial work you would normally have to do to a precast flue with cracks in the loft?

Now he's asking for £50 to do this 'check of installation'.......does that sound reasonable? If I'm in need of further help I'm gonna have to give you a call anjme.........hope you can squeeze me into your appt schedule.

Now he's asking for £50 to do this 'check of installation'.......does that sound reasonable?

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I'd say so.

£50 quid is not bad.

Although if you have paid someone already its getting expensive!

We upgrade precast flues every day. Existing gas fire should be removed, use a torch and mirror to look up into flue blocks for signs of blockage, no cracks or gaps allowed whatsoever in base of flue opening.


good luck .

flue brushes with bolster taped to end so as to knock off all the mortar overspill when built.

peca27 said:

I've just been into the loft + the party wall (where the precast flue goes up) is pretty blackish + dirty.

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Are we talking here about where the flue pipe exits the collar in the final flue block?