Help me with my flue and my shed…

So, I’m hoping to make a nice big lean-to shed down the side of the house.  And I’ve even been gifted a nice lot of timber to make it.  But the snag is that there’s a flue in the way from the gas fire.  Any bright ideas to stop me gassing myself to death every time I go in the shed?  I could replace the fire with an electric one, but I’m not sure they are as effective as gas fires.  Could I extend the flue?  Maybe have a sort of vertical chimney in my lean to?  Any ideas?

You need advice from a Gas Safe engineer, that’s not a job to go winging it on. Get it wrong and it’ll be carbon monoxide in the house, not just the shed. 

Gas engineer to either decommission the fire or extend the flue up through the roof of the shed.

Why do gas fires need a flue but a gas oven or hob doesn’t?

Replace with a double sided wood burner 

That’s a balanced flue on that fireplace, so not just a simple case of extending it. First port of call would be the fireplace manufacturers product details – they should stipulate what flue layouts are permissable with that particular appliance.

Dickyboy has the right answer, then if doable it’s a gas safe engineer. Balanced flues are not generally designed to do much more than pass through a wall.

Why do gas fires need a flue but a gas oven or hob doesn’t?

Average room gas fire is apparently 7kW & average gas hob total of 4 burners is the same but you don’t often have all of them running let alone for hours on end & kitchens have extraction – which would be defeating the point if you are just trying to heat a room.

Log burner , flue exits through wall into lean to shed. So it passively heats the area in the winter allowing bike fettling on the winter.
Then run flue up and above roofline
Get rid of the hideous 1970s had fire quick smart

Log burner flue would still need a Hetas installer or building regs sign off though.

Log burner would also need to be in a house several hundred metres from neighbours, in an area where powercuts are frequent or extended and mains gas is not available.

The presence of a gas fire says that mains gas is available…

Aren’t these gas fires massively inefficient compared to a gas boiler and rads? I’d be looking that up OP, and if my recollection is right I’d be getting that old thing decommissioned by a gas safe plumber, turn up the heating if you’re cold, crack on with the lean-to.

Never used one, but if you just want a ‘feature fire’ look at ethanol fireplaces.  

This would allow removal of the flue and maximal shedage.

Alas, not as simple as I’d hoped…

@goldfish24 – how rude. This was the peak of style when the house was built in 1995. But it is on the list to replace when we get round to doing the lounge. Bit of a way off though.

We have had the heating with new rads etc so the lounge is pretty cozy. Just put the fire on occasionally when OH wants to be specially toasty.

@spooky_b329 – just been looking up ethanol fireplaces. Could be a fuss free option. I see a new thread coming on. Could go for an electric fire but the one in our old house was really noisy. Just a fan heater with a lame “flame” effect

Who is the manufacturer of the appliance?

Most will have a number of flue options.

I.e. one that can go up the wall and put the roof of your shed.

Then there’s the plume management type flues where the exhaust part is taken upwards.

First port of call is the manufacturer.

I did similar when I relocated my boiler from in a bathroom cupboard to in the loft, i.e. bought new flue to go through wall rather than vertically, they made all kinds of shapes and options for the flue

Then you should really get a gas safe to fit the new flue, however I suspect a gas safe would just condemn your fire and refuse to work on it aside from servicing, don’t think they are supposed to commission stuff that won’t meet current regs.

If the fire is over 25 years old, any messing with it basically means a new appliance anyway. Electric or liquid fuel are basically just unbox and screw to the wall and done, but if you want to stick with gas there are now flueless versions that clean up the burnt emissions through a catalyst and return them into the room, which also ups the efficiency since no heat up the chimney or through the wall. You (or the gas engineer) can close up the flue hole and the shed can go up.

https://www.flames.co.uk/flueless-gas-fires.html

YOu can get longer balanced flues no issue – but depends on the manufacturer what is possible – you need to check with them.  thats the option I would go for

Was going to add about a flueless gas fire, but @midlifecrashes beat me to it!

We had one at our old place, replaced a flue’d gas fire. We blanked the flu off when we fitted it, but still connected to the same gas supply. Really efficient as stated above. You will need a low level air vent if you don’t already have one though.

Ooh.  Fluelass gas fire.  Another option to consider.  Sounds like another thread coming on.

Fashion and style is intersting though, isnt’ it?  What looks great and bang up to date now is likely to look pretty naff in 10 years time. And who wants to redecorate every 10 years…