Concrete hearth and brick base of removed chimney breast

[Peterpiper]

Good morning,

So ground floor chimney breast removed but concrete hearth and bricks below floor board haven't been removed. These appear to be supporting the joists so removal may lead to floor collapsing. Should I just place flooring on top after covering with DPM or do I need to take out the concrete and bricks and build flooring up? Many many thanks

 

[blup]

Sometimes the joists can rot where they sit on the constructional hearth in which case you can cut them back and sit them on appropriately protected sleeper walls (just blocks built up). Likewise if no signs of damps on hearth you can leave in place with a dpm over. But why not just dig it all out and extend the joists onto hangars where the fireplace was.

Blup

 

[Peterpiper]

Sometimes the joists can rot where they sit on the constructional hearth in which case you can cut them back and sit them on appropriately protected sleeper walls (just blocks built up). Likewise if no signs of damps on hearth you can leave in place with a dpm over. But why not just dig it all out and extend the joists onto hangars where the fireplace was.

Blup

Thank you blurp. I dug out the concrete and some of the brick work which was fairly easy as per picture. I'm now thinking of sistering the joists (never done anything like this before so excited and nervous lol) with c24 treated timber and I'll wrap ends with DPM and use M12 coach bolts with square washers on either side and the double edged middle fixing thingymabob in the middle.

Joist on one side are 4 X2 and other side 3 x2 small one is to accomodate an old gap pipe that is still active but capped above floor boards. Will get it capped below floorboards so it's not a trip hazard.



The floor boards at the moment are 130mm wide and 20mm thick. Struggling to find ones that match this size to fill the void. Any suggestion as to what I should use please?

Many many thanks in advance.


I want to do as much of the work myself as possible before handing over for new laminate, plaster and skirting by the pros.

 

[blup]

Buy wider boards and rip them down, a timber merchant should be able to do this and will supply as close to 20 mm thick boards as you can get, or plane down thicker ones. It will be cheaper to do both yourself if you have the tools

Blup