Logburner hearth on sloping floor

[LyndseyP]

Hi all,

We've just bought a logburner for our living room. I've opened the original Victorian fireplace, no problem.

The issue we're stuck with at present is that the floor in the room slopes quite considerably (by an inch from one side of the fire opening to the other!).

Now I know building refs requires total hearth to be 125mm. I was hoping the construction hearth would be plenty thick but it's about 25mm.

Our installer is saying we should have a raised hearth of 50mm, others that have quoted have said we can just tile flush to floor level. Neither of which appear to be in line with building regs.

Issue being, I don't want a raised hearth, I do want to tile flush to the floor. Can tile myself. The issue I'm having it how to make the bloomin' thing flat. I've considered skimming over with self levelling concrete but thing we'll end up with slanted sides of the hearth that will look ridiculous.

Any ideas for a way forward??

All help greatly appreciated as I'm getting pretty cheesed off with what seems like a never ending project!!

 

[LyndseyP]

Photos attached.

 

[foxhole]

Hearth can be much thinner, depends on the wood burner spec, are you saying your installer does not know regs?

 

[LyndseyP]

Not really, no. I'm not hugely bothered about the regs as I know if I were to put the burner not in a fireplace, I'd only need 12mm, so the requirement for it to be 125mm just because it's recessed seems ridiculous to me.

It's frustrating that the various installers made different assertions about the regs causing me to just look into it myself, but that's by the by.

 

[vinn]

You have two hearths: the back hearth in the recess, and the front hearth in front of the chimney breast.
Your back hearth is already raised above the front hearth with a 30mm to 40mm lip.
Is your plan to tile the recess and the front hearth at two different levels?

Both surfaces appear cracked or broken.
One possibility would be to demolish & dig out the back hearth, and infill with concrete to a surface level with the front hearth.
You could then tile through on a single surface. This would depend on the front hearth being sound and thick enough - ease out the broken corner and measure the thickness.

The cracks in the front hearth are probably due to historic floor movement.
You dont seem to have an arch or a lintel in position?
Have you read the recent mass of threads on opening up flues?
Has anybody been under the floor and examined the joist trimming around the filled in hearth?

 

[LyndseyP]

Hi vinn,

There is an arch there it's just a bit higher than the photo goes, so no worries there.

What you can see at the back is actually some bricks that are just in the fireplace rather than a back hearth- this is the third fireplace we've opened in the house and none have had back hearths (or at least they've been removed at some point).

The plan was to remove those bricks and dig out some more of the debris, then create a back hearth by bricking and the a thin layer of concrete to the constructional hearth level.

No ones been under the floorboards. The constructional hearth only feels to be about an inch thick.

Each of the installers tried to sell us on just sticking a granite hearth on top of it all, but we're really not into the look or the £300 price tag.

 

[vinn]

Best practice would be to demolish both hearths and dig down a suitable depth for a membrane and self mixed concrete to be installed.
When the front hearth is dug out you should be able to see the state of the trimming woodwork and take action if any decay is exposed.

How come the floor has such a drop?

 

[LyndseyP]

I think it's just a movement issue, the house is late 1800s and is raised about 2/3 feet above ground level as the road slopes down to the main road. I'm guessing it's just shifted over time as even though we're in a coal mining area, our coal mine search said there were none in the immediate area of the house.

Okay, we'll rip out the bricks and take out some of the damaged concrete and see what that reveals

 

[vinn]

Remove all the concrete, faint heart never fixed a broken hearth.

What did your mortgage surveyor have to say about the possible movement?

 

[LyndseyP]

They didn't say anything about it, we had an independent survey done as well and it wasn't mentioned as a cause for concern (although the previous owners had the room carpetted so it was likely less obvious).

He mentioned some sponginess in the floorboards as potential damp or rot of floor joists but once we ripped up the carpets it was just some really poorly fitted replacement boards that hadn't been tied into anything.

 

[vinn]

Believe me, if there is a significant drop in a floor then there are many ways of instantly becoming suspicious and investigating further. Exactly what most RICS house purchase surveyors dont want to do. They are a disgrace.

It might be something or nothing but if there's enough crawl space then someone should go under the floors, and examine all your joist bearings in all the walls.
If there is decay then its no big deal and can easily be dealt with.

 

[LyndseyP]

Can't say we were massively impressed with the survey tbh! Lots of the reported damp was just where the wet dog had been against the wall...

We'll have a look tomorrow. I'm surprised the house doesn't have a cellar tbh, it's the right age and raised plenty from road level so who knows what we'll find under there!