Gas fireplace - should fill void at back? Vermiculite?

Joined
27 Nov 2015
Messages
30
Reaction score
2
Location
Hampshire
Country
United Kingdom
We have a gas fireplace as shown. Recently got the chimney swept (there was a lot of sticks and birds-nest up there). Got a cowl fitted to stop them coming back.

The sweep said it wasn't right that we had a void at the back of the fireplace (which was also full of sticks).

A lot of awkward work with a vacuum cleaner and a litter-picker has got the void clean again (final pic).

Sweep suggested we fill the void with Vermiculite. Should it be finished with a concrete mix to form a shelf?

Should that copper pipe just be encased in it, or does it need protection with some kind of surround?
 

Attachments

  • before.png
    before.png
    1.9 MB · Views: 348
  • fireplace.jpeg
    fireplace.jpeg
    310.3 KB · Views: 344
  • after.png
    after.png
    1.2 MB · Views: 356
Sponsored Links
That looks like a gas pipe , you encase that in concrete and it will corrude

You have a gas fire , if a cowl is fitted then that void won't be an issue again , why was the sweep so bothered about it? Was it because it makes it easier for him to clean if you block it up?
 
Isolate the gas pipe - there should be an isolator to the right of the chimney breast .... there should be?
you need a gas safe to come out to inspect and test the installation and remove the gas fire (and later replace it).
Removing the fire you will have a free shot at any void. vermiculite's not needed.
As above, the gas pipe needs maybe repositioning, dont bury it.
Gas fires usually have a liner up the flue and a gas approved cowl.and a carbon monoxide detector.
 
That looks like a gas pipe , you encase that in concrete and it will corrude

You have a gas fire , if a cowl is fitted then that void won't be an issue again , why was the sweep so bothered about it? Was it because it makes it easier for him to clean if you block it up?

Thanks. I agree the cowl removes the main problem.
If he sweeps it again in a year or two, I suppose more stuff could come down (cobwebs etc) which could collect there. The idea of backfilling is to avoid that.

Had a gas-safe eng out to service the fireplace and give us his opinion. He agreed the backfill was not necessary, but would do no harm. He brought a huge bag of Vermiculite with him, and filled it for us (up to about 5cm under the cast-iron back plate height, so wind won't blow it out too much). he also refreshed the filler under the fake coals.

This is a dry fill, and removable. No concrete.
 
Sponsored Links
Isolate the gas pipe - there should be an isolator to the right of the chimney breast .... there should be?
you need a gas safe to come out to inspect and test the installation and remove the gas fire (and later replace it).
Removing the fire you will have a free shot at any void. vermiculite's not needed.
As above, the gas pipe needs maybe repositioning, dont bury it.
Gas fires usually have a liner up the flue and a gas approved cowl.and a carbon monoxide detector.

That would be needed if I hadn't already got the sticks out. I included an "after" picture in the original post. I also mentioned we have a cowl now - the sweep fitted it. Perhaps you just skimmed my original post?

I will fit a CO detector too, the gas-safe eng also recommended I do that. One of these perhaps:
https://www.screwfix.com/p/fireange...rm/92361#product_additional_details_container
 
Last edited:
Nope, you misread me. You mentioned "a cowl" which covers a lot of cowls. i specified a gas approved cowl - there's a difference that involves safety.
A fire like yours produces fumes not soot.
The flue should have been swept and smoke tested.
And camered - birds can enter your flue from a next flue if the feather is broken?
In future, if you annotate your pics you will be clearer.
Removing the fire would have allowed you to make good the broken back hearth and investigate and make good the gaps in the rough back wall - there might be another void behind the back wall?
What purpose a 50mm bed of loose vermiculite serves i dont know - at worst it might somehow interfere with the operation of the gas fire?
The Gas Safe should have recommended a particular choice of detectors and a detector location, he's on site. Hard wired is always best.
Do you have a gas restrictor/isolator?
 
For me filling that void with verticilite has made a fantastic cosy and warm nest for mice
 
What purpose a 50mm bed of loose vermiculite serves i dont know - at worst it might somehow interfere with the operation of the gas fire?
The Gas Safe should have recommended a particular choice of detectors and a detector location, he's on site. Hard wired is always best.
Do you have a gas restrictor/isolator?
Vermiculite was put there by a Gas Safe person ?How did you work out 50mm depth of it from the OP's post ? Maybe G S looked @ the cowl while they were there ? maybe you ask as many questions as bobasd used to ? I thought he was US based ? Are you Gas Safe registered or just guessing ?
 
Last edited:

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Back
Top