Victorian Cast Iron Fireplace installation - Decoration only

[xeres]

Hi

We are currently renovating our flat (Victorian 4 storey townhouse) and have removed the old back boiler and fitted a combi. The back boiler was put into the space where the original fire place was installed. We now want to put back in an original cast iron fireplace and I would like to seek advice on fitting.

First things first: Fitting a working fireplace is completely out of the question. This is going to be decorative only.

Secondly: I am on a budget! (no surprise!)

I have sourced a beautiful cast iron fireplace and a wooden fireplace surround which i'll be stripping back and repainting. I have also sourced a rectangular slate hearth. The original hearth was just concrete and sloped (awful) with the carpet lain across it so I have smashed it out and put floorboards into the space.

The conundrum(s) however are as follows:

1) Can I cut the Polished Slate Hearth to a T-shape such that I can sit the victorian fireplace on it? I have the evolution Rage saws with the diamond blade - anybody had any experience of this? My worry is that it'll be brittle and chip/crack etc.

2) How do I attach the slate hearth to the wooden floorboards - no more nails it? Really want to avoid pulling everything up and mixing cement or lime/mortar mixes.

3) The wooden surround is offset from the wall which means if the fireplace was fitted flush to the wall, there would be a large void space between the fireplace and wooden surround. Logic says I have two options:

- Build the Fireplace out and offset from the wall. Possibly use wooden batons? Good because you won't see it and lines will look clean.
- Put wooden batons in the wooden space and blend them in. Doable but not as clean.

Anybody else have experience of this that could give us a few pointers?

With thanks in advance.

 

[pinenot]

A simple photo will reveal all, if you can...pinenot

 

[cjcoffin]

Hi Xeres,

We have done a similar job in two Victorian houses now so may be able to help

The conundrum(s) however are as follows:

1) Can I cut the Polished Slate Hearth to a T-shape such that I can sit the victorian fireplace on it? I have the evolution Rage saws with the diamond blade - anybody had any experience of this? My worry is that it'll be brittle and chip/crack etc.

Not familiar with the saw you mention but I share your concerns. The finished job will not look authentic anyway, the T-shaped hearth is typically made of three or four pieces to allow for a certain amount of thermal expansion and settlement; certainly the slip that goes under the cast-iron grate would have been separate. (In both houses we had a slate hearth made to order like this)

Maybe take the slate to a stonemasons or monumental mason and pay them to cut it - if they won't do it the chances are it can't be done without cracking.

2) How do I attach the slate hearth to the wooden floorboards - no more nails it? Really want to avoid pulling everything up and mixing cement or lime/mortar mixes.

IMHO not a good idea, there is a serious risk of the slate cracking with movement especially as its a single big piece. Better to have left the concrete and set the slate on top with weak sand/cement mortar or (now) if a ground floor room create a new bed from the ground up. If you don't want to do this then put something slightly compliant between slate and the boards e.g. high density foam or even carpet underlay and then pray.

3) The wooden surround is offset from the wall which means if the fireplace was fitted flush to the wall, there would be a large void space between the fireplace and wooden surround. Logic says I have two options:

Assuming the wooden surround has good proportions the end result will look better as the designer intended i.e. set the fireplace up against the back of the surround even if you have to build it out from the wall. Ideally this would be done with masonry/plaster/fire cement but if it is purely decorative almost anything will do. If you use wood leave a gap for some fibreglass insulation or fire rope on the inside edges in case someone ever tries to light a fire. N.b. even if it is purely decorative I think you are now supposed to put an installation certificate saying so next to the fireplace or by the fusebox. Especially important if the chimney has been blocked/capped or is otherwise unusable but equally so if there is a boiler behind it (what is the access for servicing?)

HTH

 

[xeres]

Plan to post up pictures but its covered in junk atm - will do so this weekend.

Thanks HTH, some great advice in there. The good news is that although I removed the cement, it was essentially poured onto stones and rubble which is still in situ. The boards are actually only screwed down approx. half a meter out from the fireplace as there are no joists going across (for obvious reason). We live in the 1st floor flat. In effect, the boards are lying across these stones so I assume it wouldn't be too much hassle to pour self levelling cement after cutting them back. The original hearth was a mess and not even level so sticking the new hearth to it wasn't an option anyhow.

As regards the certification, this is new to me. I'll get in contact with building control for advice on this.

RE: Boiler. The back boiler has been removed and a combi boiler put on the wall.

One other thing I have just thought about is blocking off the chimney. Currently, the old flue from the back boiler is hanging limply behind. Pulling it out is not an option and neither is access to the roof of the property. Anyone know what options are available to me?

Thanks all

 

[cjcoffin]

One other thing I have just thought about is blocking off the chimney. Currently, the old flue from the back boiler is hanging limply behind. Pulling it out is not an option and neither is access to the roof of the property. Anyone know what options are available to me?

Thanks all

Ideally you should have a ventilated cap put on the chimney pot to stop birds and stuff falling down. But if the fireplace is open anyway you will be able to clear up anything that comes down. You could install a chimney balloon to stop this and keep out draughts but if rain can get in the top it is good practice to allow some ventilation.

A working cast-iron fireplace will have the void behind filled in with rubble and capped with mortar to prevent anything falling behind the sides and back where you can't get at it, worth thinking about. Maybe however the old flue lining is long enough to direct any debris into the grate where you can get at it.

In our current house I made a "gather" out of sheet metal to form a hood to the fireplace and fixed the flue lining to the hole in its top in case anyone wants in future to put a coal-effect gas fire in the grate (my wife hates them). The lining is only suitable for gas (it was installed for a Baxi back boiler), you need a larger diameter and higher grade lining for solid fuel.

 

[xeres]

Thanks CJ (not HTH - not sure what that acronym is for!?)

There is a chance I could get on the roof if scaffolding is in situ when the managing agent decides to get on with works. If so, will try and cover with a grate then. Currently, small debris comes down through the flue that is light brownish in colour and gritty. I assume the wind will dislodge things into it.

I like the idea of the gather - wishing now I hadn't thrown that away when I removed the back boiler as that would have solved this quickly and easily...!

One point to consider - I have never seen any rain come into the flue. I would assume this should not happen and that it's absence should be expected but don't know if this could have a bearing on whether to choose if we wish to put a balloon in it. Can these balloons be removed and reinserted such that you clear any debris bearing on it periodically?

***

As a seperate aside, I just realised another little problem I may have created myself in the other room. There was previously an louvred brick in the place where the fireplace used to be. I note this is consistent with all the flats in the property. I have recently discovered that when closing chimneys, its custom to put an air brick at the top and at the bottom. However not knowing this, we just replastered the room, knocked the louvre/air brick through and filled/plastered it over such as there is no ventilation through it. We are on the 1st floor so I assume damp is not going to be a problem, particularly if there is vents/air bricks in the other flats and we are in the middle...?

Appreciate your time and help here.

 

[cjcoffin]

Thanks CJ (not HTH - not sure what that acronym is for!?)

Hope This Helps(!).

One point to consider - I have never seen any rain come into the flue. I would assume this should not happen and that it's absence should be expected but don't know if this could have a bearing on whether to choose if we wish to put a balloon in it. Can these balloons be removed and reinserted such that you clear any debris bearing on it periodically?

Yes they can, but personally I would not use one unless there is a totally unacceptable draught in the room. If you look at the typical chimney construction in a 4-storey town house (we used to own one) the chimneys all have at least one bend in them to get round the fireplaces in the room above and/or to bring them all together in a single stack at the ridge line. So most of the rain that comes in the chimney pot does not make it to the fireplace but gets absorbed into the fabric of the building so you don't notice it. The damp can however cause (i) tar stains to migrate to the surface of the chimney breast (don't bother with International stain-block paint, it does not work, 2 coats of polyurethane varnish are much better) or (ii) efflorescence in the plaster, possibly in someone else's flat in either case. Hence it is customary as you note below to put an airbrick or Mapvent if a fireplace is blocked up, the current of air will keep the chimney dry and sweet.

As a seperate aside, I just realised another little problem I may have created myself in the other room. There was previously an louvred brick in the place where the fireplace used to be. I note this is consistent with all the flats in the property. I have recently discovered that when closing chimneys, its custom to put an air brick at the top and at the bottom. However not knowing this, we just replastered the room, knocked the louvre/air brick through and filled/plastered it over such as there is no ventilation through it. We are on the 1st floor so I assume damp is not going to be a problem, particularly if there is vents/air bricks in the other flats and we are in the middle...?

Appreciate your time and help here.

No trouble, I am waiting for replies to another posting on here and for the boiler repairman and drainage contractors to turn up. Lots of useful advice here http://www.victorianfireplaces.com/guides.html and on the various other suppliers' sites (some diametrically in conflict!).

 

[xeres]

Bugger, so now I may have to retrofit a vent. There was previously a louvred vent fitted which I punched out and filled with expanding foam. Walls now skimmed and fully decorated

Any advice on easy retrofitting here? Was thinking buying a vent and pin drilling a square hole for it to fit in.

Thanks

 

[xeres]

Bugger, so now I may have to retrofit a vent. There was previously a louvred vent fitted which I punched out and filled with expanding foam. Walls now skimmed and fully decorated

Any advice on easy retrofitting here? Was thinking buying a vent and pin drilling a square hole for it to fit in.

Thanks