Covering gas fire hole/flue and venting it.

[Mikey_B]

Hi everyone

I'm not sure if this is the ideal area to post this, but I'm hoping you can help me make sure I've got the right idea about some work that needs doing in a house I'm buying. The place is a 1974 semi which originally had a gas fire. The current owners had this removed - the gas supply fittings were capped off professionally and they fitted an electric fire over the top. For space reasons, I'm now going to remove the electric fire and cover off the hole.

Though I'll be getting most (if not all) of the work done professionally, I want to ensure I understand what needs doing and the way it should be approached. I've done a bit of research, so could you please comment on these points and let me know if I've got the right idea?

- The intention is to cover the interior hole with plasterboard by fixing wooden batons to the interior to the hole and the board then onto these. I'll then get it plastered over.

- The work needs to be vented, to stop build up of condensation. I understand I could fit an interior vent. I'm not sure if I'll use a plaster vent of a plastic one. Would a hole for the vent need to be cut out after the plastering is done and it has dried? Would a plaster vent be easier to fit (during plastering?). Would a vent listed as 'not suitable for use with gas appliances' be fine (since there are only capped-off gas fittings present)? Would fitting an air brick to the external side of the flue be a better option?

- I will need to get the top of the flue capped off with a rain proof vent (if not done already)

- Will moisture from the airflow be an issue to the plasterboard? Is bricking the hole up a much more advisable option? Would board then need to go onto the brickwork for plastering, or am I right to think it could be covered with a layer of PVA and then plastered directly?

Again, I won't be attempting any of the work that obviously needs a professional hand (e.g. plastering for sure), but just want to understand what actually needs to be done and how.

Thanks very much
Mike

 

[vinn]

All redundant flues need venting top and bottom and smoke testing.
However you block the opening the vent can be plugged and screwed on or glued on - the vent hole can be opened at any time but best before any plastering.

 

[Mikey_B]

Ok, good to know, thanks Vinn. I'd assumed that plastering with a hole already cut in for the vent would be difficult, but that's not the case then?

Regarding venting at the top - the flu vents out through a sort of vented tile on the ridge, as far as I can tell at present. Would that constitute venting at the top?

Since posting this I've actually been wondering if adding an external air brick at the bottom of the flue is actually the better option - no annoying vent on the wall inside that way.

 

[vinn]

If you insert an air brick on the outside then brick/block up the fireplace opening.
You must still sweep & smoke test the flues.

Has the chimney breast been removed from the floor(s) above or from the loft?
Or does your chimney breast in the loft rise up to the ridge below the "ridge vent tile"?
A photo of your roof and ridge vent would help?

 

[Mikey_B]

The hole originally accomodated a gas fire, so it's a gas flue, not an old fireplace. No fireplace on the upper floors. The gas fittings were dealt with by the current owner who has already replaced the gas fire with an electric one. What I'm now looking to do is remove the electric fire and seal up the hole. Does this affect much of what you've said?

There is no chimney breast - just the vent tile on the roof ridge, as mentioned. I'm not in the house yet, so it's hard to say, but given how it looks from outside, that's where I imagine the flue vents to. I understand being vague doesn't help get definitive answers of course.

Not sure if I've confused matters with talk of the external air brick - I'm not even sure that's an option with a gas flue? I haven't even seen inside the hole yet.

Thanks for the help
Mike