How to cover floor after removing fireplace?

[ksashok]

Hi Workshop Community, 

I wanted to remove this non functioning gas heater from my house. I got the plumber to remove the heater and cap the gas line.

How it was at first

After removing the heater, I could see that this was a fireplace previously and had hearth underneath. We removed the bricks and want to patch the wall flat.

The current flooring is laminate with timber flooring underneath. I want to remove the laminate and then sand and polish the timber floor. The house is on stumps.

But this part near the heater is concrete which is at the same level as the timber flooring. I could see the ground underneath.

What is the best way to lay the timber board at this part where there is concrete?

Thanks in advance.

[EricL]

Hello @ksashok 

Welcome to the Bunnings Workshop community. It's sensational to have you join us, and thanks for sharing your question about your flooring.

Thank you very much for sharing those photos of your fireplace. I suggest breaking the concrete floor apart in order to install timber flooring in that section. However, before you begin, I suggest doing a bit of an investigation to see if the concrete is thin or is a solid block of concrete. Once you find out you'll be able to get the right tools to break it apart.

Let me call on our experienced members @Dave-1 and @Nailbag for their recommendations.

If you need further assistance, please let us know.

Eric

[Nailbag]

Hi @ksashok 

I would hire a a pneumatic hammer drill with a stop rotation function which is used for chiselling, like a mini jack-hammer. Use a wide chisel to take the top layer of the concrete pad away so it lower than the floor boards. The slab is thick enough a reinforced so that there isn't any chance of collapsing with the small amount you need to remove.

Pack under the hole cavity with rubble and fill the top gap with concrete. Doesn't have to be pretty just sound.

Then lightly fill the seal with a levelling compound so that it brings the level of the slab to the exact level of the floorboards allowing you to then continue the laminate flooring.

Nailbag

[Dave-1]

Good Morning @ksashok 

Im thinking of removing the concrete plug/slab so you can build a frame to support new boards in that area. I dont know if it would be possible to only take some of the height of the concrete, I suspect not but you could have a try. then you could use the leveler as @Nailbag has suggested and lay the new timbers on the lowered surface. I think a new under frame section to support the new floorboards will be easier.

That gas pipe, is it a live pipe and capped? I would be cautious while breaking up the concrete with it. Have just had a last look at your photos, does the brick pillars for the old fireplace continue through to the underside of the concrete slab? I would invistigate that first as it will change how you break up the slab and support the rear of the fireplace.

Dave

[ksashok]

Thank you @Dave-1 and @Nailbag @for your help. I’m thinking to put hybrid flooring on top instead of polishing the timber. 

could you suggest on how to manage this concrete section? Can the hybrid flooring be done directly on top of the concrete by levelling? Or is there a better option? 

thanks a lot for your help. 

[EricL]

Hello @ksashok 

I suggest following @Nailbag's recommendation and re-level the concrete section as it is not level to the existing floor area. The gap can be filled with timber panels that are the same thickness as your existing flooring. You can then lay the hybrid flooring over the existing floor.  

Eric

[Nailbag]

Hi @ksashok 

I used self-levelling compound in the area under the timber frame after I also had to chisel out large section of a top level concrete bed. Then I screamed the compound smooth to the top of the old tiles and then laid the floating floor straight over. The boards used had a decent rubberised underlay.

Nailbag

[ksashok]

Hi @Nailbag 

Thanks a lot for the detailed explanation. The concrete is around 10cm thickness. So I think it might be difficult to scape only a portion of it. 

Like @Dave-1  mentioned, could I remove the concrete completely and use a timber frame to join the existing frame with something like a pryda-joist-hanger-to-suit-35-x-90mm ? And then add structaflor-19-x-3600-x-600mm-general-purpose-yellowtongue  on top of it to be at the same level as the timber? 

[ksashok]

Hi @Dave-1 ,

The gas pipe is live and capped. The plumber removed and capped the gas line.

To answer your other question, I had a look under the brick pillars and it goes all the to the ground underneath the fireplace.

So I assume it would be safe to remove the concrete slab? 

I have the ozito-1500w-5j-rotary-hammer-drill-kit-rhd-1550  which I could use to remove the concrete, but I'm worried on removing near the fireplace as I could damage the bricks. Is there any specific tool to make a cut on the concrete and then I could use the rotary hammer drill ?

[Dave-1]

Good Afternoon @ksashok 

The hanger you mention would be ok, tho I was thinking of more attaching timber to the side of the existing supports to create a ledge. The hangers would probarlly be more of a correct way to go.

I would be thinking of a concrete cutting saw (hiring one) and cutting across the front between the brick pillars. That way you would lessen the chance of a crack being transfered from the slab to the brickwork. The concrete may not be too thick and hopefully a few hits with a pound hammer or a sledge hammer will crack it nicely.  Slow and steady is how I would procede until you have that air gap cut.

I havnt had a lot of success with any small powered hammers. No harm in trying. but the cuts would be my first step.

Dave