Pre cast flue too small

[Garetg5]

The starter block of my pre cast flue is only 300mm wide and will not accommodate the inset gas fire that we wish to have installed. Does anyone know if it is possible to remove the existing starter block and fit a wider one that would taper into the existing flue? Thanks

 

[namsag]

Yes it can be done, but the awkward bit is finding one with the right taper as the sizes have changed over the years.. Also the fire instuctions will tell you the minimum cross sectional area and minimum internal dimensions required in the blocks. And some of the old blocks do not meet what is required.

Some insets can have a spacer kit to save you altering starter block or if it`s in a surround it can have a built in rebate

 

[anjme]

Is the flue system on an end gable wall?
Or is it a party wall with neighbours or internal room wall.
If its the latter you may not have enough depth.
You should be able to pay a small cost for a flue survey. If the starter block is that small it may well be that it is an older type pre-cast system and there could be numerous other defects that require upgrading to safely install and use a modern inset appliance.

 

[Paul Barker]

Also be ware, many precast flue block systems were very badly put together and spill terribly. We have an estate round here, whenever I go to a house there I cap the fires off as imediately dangerous. I am not being meladramatic here, the spillage is so bad the walls above are stained, though I do confirm it with a smoke match there is no need, the evidence is there before your eyes.

There is no remedy barr rebuilding the house properly.

At the very least get a CO detector, but watch the spillage test being done and make sure that not one wiff of smoke evades the draw.