Cracked granite hearth due to rising damp?

[ness13]

Hi, I wonder if anyone can give me some advice. We had a granite inner hearth and multi fuel 5kw stove installed in December (we already had a granite outer hearth). There is now a crack the full width of the inner hearth where one half has slightly risen, the crack is the full depth of the granite. The engineer came this morning and said it was due to rising damp, I cannot find anything about this online and wondered if anyone could tell if this is the likely explanation? Thanks

 

[Burnerman]

Never heard of that one.....is there any possibility that whatever substance the hearth was built on has subsided?
Ideally there should be a nice concrete slab underneath.
John

 

[Bosswhite]

Credit to the engineer to think of that excuse

As Burnerman said the Granite should be bedded down an a concrete slab.

 

[freddiemercurystwin]

Utter *******s! Sounds like the engineer is defending a poor installation. You won't find anything online because its baloney. As John say, sounds like the substrate is to blame ....... Which then begs the question who did the slab or substrate and what is it that the granite is bed on?

 

[ness13]

Thanks for your replies The company I bought the stove from did all the removal and installation work including the concrete base. The seam between the inner hearth and outer hearth has come apart and the outer hearth has also shifted forward in the area where the crack is on the inner hearth.

 

[ness13]

Update! Was called this morning to be told that the cause is damp and I will have to pay to have someone come in and test and then pay to have damp proofing installed and pay out again to replace hearth and fibreboards?????

 

[freddiemercurystwin]

Utter rubbish, prolly better off posting in the Building section, sounds like you'll need to go through the whole getting a report by an independent someone or other and getting a solution that way ........ if they continue to fob you off.

 

[ness13]

Is it safe to use the stove when there is a gap along the fibreboard and register plate which could alow smoke/ carbon monoxide back into the room?

 

[freddiemercurystwin]

You're actually asking if it is safe to use a fire when you think that there is a possibility of carbon monoxide leaching into the room?

 

[ness13]

Not planning on using it, just wanted to confirm! but they didn't advice us to not use it just proving how they didn't see fit to mention it