Finishing Timber to Hearth

[padstar]

I have not yet installed a hearth to the fireplace but am about to lay the engineered timber flooring to the room.

The fireplace is due to have a wood burner in it.

How should i finish the timber. Someone suggested laying the timber everywhere and then installing a hearth on top to the fire place. I am not sure this is the correct answer?

I could run the timber flush along the front of the fire place (but not in it) and then fit a hearth so that it is bedded on mortar in the fireplace and on top of the timber to the front?

What options do i have here?

I was thinking leave the timber out of the fire place and cut roughly to where the external part of the hearth would sit. Then once the floor is laid infill with latex or screed and then bed the hearth on top of this over sailing the timber by 20-30mm. If i latex level or just below the timber by time i bed onto the mortar the hearth will sit a few mm above the timber and allow the wood to move slightly under the overhung section of stone? Does that make sense?

 

[kp00110]

I have just had my hearths redone. I think it would be best to install the hearth prior to the flooring. Hearth stone should be bedded onto concrete construction below I believe, not just mortar onto a timber floor. If you get the hearth in first, properly bedded, the floor can be finished nicely flush to the edge of the stone. This also saves damaging the nice new floor by the builders etc building the hearth

 

[oldbutnotdead]

You need to have a look at some Approved Documents (aka building regs) for what is acceptable as a hearth. Much better to sort the hearth out then floor up to it- avoids any problems to do with minimum thickness of superimposed hearth and adequate support for the (fairly heavy) hearth and woodburner.
Plus you don't want mortar, bricks, dust etc tramped into your brand new shiny timber floor.

 

[padstar]

This is what i am thinking.

So basically the hearth would overhang the timber by 20-30mm something like that.

 

[padstar]

I have looked into the regs and the hearth must sit 300mm in front of the burner and 150mm to each side. This is what i have allowed for. Just waiting fro the stone to be cut which wont be until weeks after the timber is planned to go down.

 

[oldbutnotdead]

How thick is the stone? And in any case, the stone will be being cut to precise measurements- lay your timber floor to those measurements.

 

[padstar]

25mm thick. I was worried a bit about tolerances and being left with a small gap hence the minor overhang.

 

[oldbutnotdead]

Mmm. A really picky BCO or HETAS type could reject the hearth as not thick enough for superimposed.
What tolerances are specified in your contract with the stonemasons- stuff like that I would expect to be cut and polished to the millimetre.

 

[kp00110]

I would if laying the floor first, then trim the timber floor back after laying the stone on top and marking out the perimeter etc, cut with multisaw or something and silicone etc any mm gaps . I dont think stone on top of wood is good tbh

 

[padstar]

Would the BCO class it as a superimposed hearth if it is sat onto the original concrete base?

 

[kp00110]

no idea but before the new hearth wasnt there something else ? such as tiles etc? surely not just concrete original hearth?

 

[padstar]

Tiled originally

 

[oldbutnotdead]

Long as it's sitting on a non-inflammable surface it's fine - sitting on top of inflammables is where they get excited.
Your wood under 25mm stone sketch is going to leave you needing some sort of trim/sealant anyway so there's no real difference (apart from having to trust the measurements tho think someone mentioned using a multitool to trim the boards when the hearth actually arrives