Thinking about getting a wood sotve for the house.
Underneath the sink/bar I have a "niche" about the size of the stove I want.
Am I asking for trouble to put the stove down here (with respect to the concrete) or will I be fine provided I don't over heat it.
The other solution would be to play with the Hammer and the plaster but I would like to avoid that.

The stove: http://www.castorama.fr/store/poele-a-bois-hf-1440-7-kw-PPRDm559879.htm

Thanks you very much.

"Am I asking for trouble"

yep. where do you expect the smoke to go for a start?

Well I have a non working gas heater so I would have a tube to go to the gas heater vent (it goes out of the house, very high as well so I won't get stuck with the smoke).
My concern was more about how the concrete will cope with heat.

Concrete is fine with heat. If it's old and crap and thin you might get a crack, but it'll be fine otherwise. You can always tile over it.

building regs (they are a strange english tradition, prob dont have them in france!!!) state you need a set distance around a stove which is 150 mm to a non-combustible wall. It is likely that your gas flue wont be the same catagory as req for a wood burner.

Check out http://www.stovesonline.co.uk/stove-installation-building-control.html

concrete is fine but just plugging a woodburner into a hole in the wall might not be.

concrete will start to spall at 250 deg C + and will start losing its strength at 300 deg C +

wwaswas any pointers to why?

As far as I can see I'll make sure the whole hole isn't filled with the stove.
Plan is to have the tubing to go straight up into the chimney and straight outside.

However being naf in building regulations I am happy to have any pointer and how to.

Phyncra looking to your link now.
I'll post up pic of where tonight.

why don't you put some paving (yorkstone or something) on top of the concrete in case the concrete is old and thin

i would be more worried about fueing the smoke out

As said, building regs specify the requirement for hearth that the stove must be mounted on. You can bypass this, but you have to demonstrate the how much heat is conducted through your hearth material.

If you plan to use the existing gas vent pipe as your flue, er, don't it won't be up to the job.

There is recent thread on here discussing the flue pipe requirements….

I'm a bit confused juan, without pics but you said you were going to put the stove under a sink/bar, not in a chimney.

there are quite a lot of building regs around this sort of stuff to stop you gassign yourself on the byproducts of burning things.

I'd talk to someone who knows what they're doing (which isn't me beyond me saying 'be careful') before trying any sort of diy bodge up.

You could always spec the concrete mix with nylon fibres in case of serious heat build up. That's what the tunnels guys I work with seem keen on at the moment.
I really would make sure that your flue is appropriate before setting fire to your house.

You need to download part J of the building regs from the .gov website. You can look in there for all the details you need, including answering your hearth question.
I followed the rules, – never having done one before, and the building inspector passed it without a hitch – You MUST follow the regs though, they are made for a very good reason. Solid fuel stoves get bloody hot, and need adequate ventilation.
You also can't use a "tube" as you say for a flue, it needs to be the proper stuff, twin wall insulated. I used Poujoulat brand, but there are others. It's expensive.

How are you going to use the sink if there's a stove right under it?

Building regs not wholly appropriate, as Juan is in the south of France.
But they could serve as a useful guide, and then something to start the fire with.

Ok I'll post pictures and ask grandad he might give me some usefull tips. LOL at mugsys_m8 that is so true and I am still waiting for you to come down south at some point you know 😉