Building a Constructional Hearth - Tips and Advice Needed Re-generate an old or tired space and give it a fresh breath of life. Click here for answers, information and tips

[1.fcn]

Hello all, new on this forum.

I'm restoring a fireplace recess in a Victorian house (circa 1860) and want to ensure that the hearth in particular conforms to building regs. I plan to have a small wood-burning stove installed at some point in the future, once finances have recovered a bit.
So far, I have this:
- a bare recess with exposed bricks to all 3 sides and an opening above to the flue (some of which need repointing and restoring - I will be doing this using more bricks i am going to order,plus lime mortar)
- in the base of the recess, the old fire brick
- in front of the recess, engineered oak floor, resting on top of 21mm plywood, which in turn rests on top of closely-fitting joists

This floor is raised ground and has a basement floor beneath.

I have contacted my local council building regs dept and read stove installer manuals online and based on the info received I plan to:
- repoint and restore the brick inside the recess.
- cut away the engineered oak floor in front of the recess, to expose the plywood.
- place a master board over the plywood.
- then brick hearth on top (I am aware of all the regulation measurements that a hearth has to comply with and the reg distances for a recess into which a stove is fitted).

What I need to check and double check, in order that I don't get any regulation material wrong is this:

Is it 100% ok to build a constructional hearth as I've outlined above and what else should I know, before I start? Have I missed anything?
Is lime mortar the best to use in this instance?
When an installer comes to install a stove at a property which already has a hearth etc in situ, what exactly will they be looking for in order to 'pass' the existing hearth and surrounds in their safety certificate?
I am proficient in this level of DIY, by the way!
Obviously I will be using a HETAS registered installer to install my stove, once the time comes, but in the first instance I want to be 100% clear on how best to construct this hearth, so that it complies fully and is safe.

Many thanks in advance for your input.

Frank.

[welsh brickie]

the main thing is that you use non combustable material for the hearth, you can use tiles, or brick it doesn't matter, use cement board on top of the ply, and build your brickwork or you could mix concrete and tile over it

[aclifford]

The constructional hearth must be:
- at least 125mm thick
- project 500mm forward of the jambs
- 150mm wider than the fireplace recess on both sides.

You better make the hearth from concrete.