Was my hearth fitted correctly?

[SquareBoy]

Hi, I hope this is the right place for this. I recently bought a hearth and had it fitted. The hearth is for an electric fire so it's all in one piece and I believe fairly thin as hearths go.

The hearth is in a standard rectangular fireplace. The hearth sticks out 3" and spreads out about 3" wider than the fireplace hole.

We recently noticed that the hearth has cracked and one of the 3"x3" sections is now separated from the rest of the hearth (although not movable).

The break looks like the main hearth is now about 3mm further back than the square bit, which is jammed right up against the wall.

Our best guess is that it happened when my dad shoved a plastic toy box into the hearth (fairly hard). This must have moved the entire hearth back until the corner hit the wall and snapped.

So my question is, should this be possible? The hearth was laid on some cement which I would have thought should have held the hearth in place.

The shop that supplied and fitted the hearth are saying that it's our fault it has broken and I'd like some opinions on whether it was poorly fitted or whether we need to be a lot more careful with hearths in future.

Thanks for any opinions.

 

[Burnerman]

If the hearth was correctly laid on a bed of cement, then there's no way it should have budged......it sounds like the hearth didn't adhere for some reason.
A thin hearth especially should be supported all the way round, just in case someone treads on it.....one sure way of cracking the thing.
John

 

[SquareBoy]

Thanks for the reply, any other opinions gratefully received.

I'll probably be heading down to the shop tomorrow, and I need to work out how reasonable it is to push them to replace the hearth.

Burnerman - I'm guessing from your name that you know a fair bit about fires, is that correct?

 

[Burnerman]

I'm a retired teacher / mechanical engineer, mate - refuse all imitations but we'll all try to help when we can.
John

 

[FiremanT]

If the hearth was correctly laid on a bed of cement, then there's no way it should have budged......it sounds like the hearth didn't adhere for some reason.
A thin hearth especially should be supported all the way round, just in case someone treads on it.....one sure way of cracking the thing.
John

You really cannot say that sort of thing with certainty! The OP has already admitted that they abused the hearth. I don't actually understand what type of hearth is being described.

A hearth is normally supported all around, but that doesn't prevent damage by folk hammering it! The mortar doesn't "adhere" in the sense that glue does. It will prevent movement in one direction only. Tiled hearths will crack with the smallest effort, and marble is full of breccia (cracks), any of which are able to break given enough assistance.

 

[SquareBoy]

Thanks for the reply. I had a fairly long and amicable discussion at the weekend and the shop offered to replace the hearth at cost which we accepted.

They have also allowed us to make a couple of small changes to the material and design so we end up with a hearth that suits us better and should stop the same thing happening again.

 

[gasbanni]

when itsinstalled make sure the slips ( not the edges under the main hearth panel) but the shorter pieces that are under the body of the main hearth also have compo on them.

That way you should be able to stand on the hearth without it cracking.