Fireplace prep

[SteUK]

Hi chaps,

Not sure if this should be in this section or building but...

I am preping our fireplace so accept a class 1 inset gas fire, obviously I am doing none of the gas work myself. I have had a chimney sweep in to do his thing and he gave me some advice on prepping but want second opinions as I obviously want to do everything within safety bounds.

As you can see from the images below, the fire is far smaller than the opening. The sweep suggested sheet steel to funnel into the chimney opening, as you can see it is very square currently. Is this the best material to use? Or would it be better to use something like plaster/concrete board with a skim of plaster over the top? I am going to have to close up the sides and back fill behind somewhat as well, best materials for this? Fire cement and brick?


Thanks in advance!

Ste

 

[SteUK]

Yes that is woodchip on the wall, and there was a live electrical socket in there when we took the old fire out.

 

[gigz]

Check the M.I.'s instructions it will give you a min and max dimensions, you can use brick and cement to make opening smaller,(or a hot box) i usually use bonding and render smooth inside. More importantly (cant make it out in pics) is the polo (slab with hole in it) is there a liner in there ? if so you will need to either put a new one in or take it out and open the hole to 9" sq. I would get in touch with the fitter who's doing the job and get him to call in then you can get it from the horses mouth. Is that a robinson willey fire you're fitting ? Also that wooden lintel will have to go.

 

[namsag]

Do not back fill behind the fire, do not make a metal sheet to funnel to flue. Do not take advice from a chimney sweep get the proper guy in, usually a standard openin is 16 inches by 22 inches . So get rid off the wood and brick up the opening to the sizes given in the book usually a max an min is given ,go for just a few mil above the minimum size

 

[SteUK]

The sweep that came said the liner was fine, think it is 8 and a half inch diameter best measurement. Starts above the polo. Will take a closer picture.

It is a valor seattle (deep inset). MIs say:

Max width: 45.7cm
Min depth: 21.8cm
Max height: 57.5cm

Current opening is 54cm(w) 37cm(d) 94cm(h).

So some way off! No max depth is mentioned so should I only be concerned about filling the sides in and creating a funnelling towards the chimney opening? Bonding in 15mm coats is about 3 layers either side...acceptably safe? What would you recommend is the best way to reduce the height?

 

[namsag]

No need to do any funnelin at all just get front of hole ok.
Make the width 415mm
the height 560mm from hearth or whatever other fireproof base you are using
Depth doesnt matter in your case as its big enough

various ways of doing it but a cut down paving slab and mortar should give you the 2 and half inches you need to take either side in by then a lintel on top of them and bricks or breeze to fill in

 

[SteUK]

I was originally thinking of using paving slab, superb! Any excuse to get the angle grinder out

Thanks chaps!