Hi all, thanks for a great forum. Was hoping to pick the collective brain on my downstairs refurb. Have taken down a wall to open up the kitchen and create a kitchen diner. There was a about a 2 inch difference in level between the two rooms but the builder had to replace all the joists and was going to level up. Which he did, kinda.. Total area is about 45 sqm. The builder put in new joists, 150mm across sleeper walls (max span about 1m) with insulation and UFH running between and then topped up with 20-30mm screed and finished with 18mm WBP ply. I let this dry out for about a month with dehumidifier running and tested with a pin type moisture meter - ply readings were around 10%. Whilst the two rooms are closer, levels are over the place with about 20mm diff from high point and not flat at all. Putting down Quick-step LVT click in. Having lost faith in my builder, I decided to tackle it myself by putting down Mapei Ultraplan renovation screed. Prepared the ply by cleaning it, filling joints and any cracks with Mapei Planiprep skimcoat and primed with Mapei Eco Prim T. My only help so far is a 9 month pregnant wife so no way I could have done the whole area in one go. I started with the first 60% of the space which I in turn divided in 3 sections and did each (so I have 2 joints already). Average depth probably around 12mm. Took me close to 20 bags .. End results are actually pretty good, 1-2mm dips across the 2m spirit level. I'm dreading finishing the rest which is on average deeper, is there any way to save on both cost and effort? I've heard about mixing in aggregates to reduce the amount of SLC or just mix up some sand and cement to fill up first and then top off with the renovation screed - is that viable options or do I just need to bite the bullet? Apologies for long winded question, couple of pics attached. Thanks in advance Dan
The builders put down the ply but had left it open to dry out first. We were away at the time so couldn't check how or moisture levels but probably about a week or so open before ply went over. Then another 3-4 weeks with heater and dehumidifier.
The screed will time months before dry so would of been best to miss the plywood out and put a liquid dpm down
Great, due to possible moisture from underneath? The missus is about to give birth any week now so need to get a kitchen in, so for the renovation screed already down, will have to suck and see I guess. Should I just take up the ply at the rest of the area and let that dry out a bit longer then perhaps. When dry, anyway of reducing the amount of renovation screed needed or just go ahead with a full swimming pool of SLC?
