hammerandnails

Cheers Conor

Nice one, thanks. What ratio mortar mix is recommended?

Hi all, I'm replacing some door linings in a 1960s property which is mainly made up of clinker blocks, some of which are quite brittle. When I removed a door lining (held in place by cut nails) a big chunk of one of the blocks came away with it (lesson learnt!). I have some questions on how best to put this right: 1) What is the best way to repair this? 2) Should it be patched up before or after the new door linings go in? Doorlinings will be fit by a professional chippy. 3) Can it be filled with bonding when it gets re-plastered? Thanks! (pics attached)

So, having just spent the majority of the bank holiday ensuring the entire area is deflection free I'm now confident that the floor is rock solid. Taking into consideration ease of installation, floor height build-up, thermal conductivity, and structural properties, I'm leaning heavily towards the NoMorePly boards. Is there anything I might be overlooking here? Only downside is the cost (~£300 more expensive than the ply + backerboard).

Hi Nick, Thanks again for the extensive reply, I appreciate it. Quick question about the Karndean - if the "subfloor deck board" is the 22mm plywood, surely I wouldn't need another layer over this, and could fix the Karndean straight to it? Cheers

Cheers, Nick. Having spoken to my tiler, his recommendation is as follows, with justification in brackets: 1. Plywood deck 22mm (rather than chipboard because the tile adhesive for the backer board adheres better apparently) 2. 6mm Hardie Backer fixed to plywood with adhesive and screws (better finished tile adhesion to the backerboard rather than plywood which tends to "suck" the adhesion out of the tile apparently). 3. Tile on top of backerboard Alternative and simpler option would of course going with a floor like Karndean!

I've had a look online and plywood's conductivity is around 0.13mK whereas this NoMorePly stuff is 0.172mK. Despite it being cement-based, this doesn't seem like a huge difference to me (or am I wrong here?) - especially when compared to a proper anhydrite screed which is more like 2.2mK.

I’m not entirely sure what’s causing the slight deflection to be honest. My builder is confident that once the floor deck is on (likely to be 22mm) it will remove it anyway. Yes, the pug screed is level with the joists now. Thanks for your advice with the flooring, I’ll chat to my tiler about it.

https://nomoreply.co.uk/tg4-floorboard/ This is the product I’m talking about - it is a structural 22mm floor that can span up to 600mm. Board ends apparently don’t even need to end on a joist.

Correct, currently nothing over it as we decide what deck to go with. I’m also leaning more towards the NoMorePly floor as it is structural. I will speak to the tiler to confirm but he says he has filed onto it before.

The t+g floor is there to act as the structural deck that the UFH company specifies. They don’t say what it needs to be exactly, only that it needs to be a “structural deck” of some sort (they give plywood as an example). The NoMorePly floor is structural.

What I meant is that with some options it involves screwing additional backerboard down once the subfloor is screwed down, therefore the joists will not be visible and the risk of hitting an underfloor heating pipe will increase.

We did consider this, however with our current door and ceiling heights we wanted to minimise floor build-up as much as possible. The pipe and screed on top of the insulation have already been laid so I’m reluctant to rip all that out and pay for a new system!

Yes, all options involve gluing and screwing to joists, as well as glueing the tongue/grooves.

100mm of PIR underneath the screed. Sorry should have mentioned that! The void beneath is a good 800mm with plenty of air flow too.