Another over-enthusiastic DIYer here reaching out to the pros’ for help! Currently mid-renovation of a 110 year old house. I’ve added a rear extension with a concrete floor that joins to an existing suspended timber floor which is made of 18mm boards sat on walls/brick pillars. I’ve replaced a quite a few rotten boards/joists near the new concrete and plan to put 18mm ply to match the existing board in these areas. Surprisingly, the rest of the floor is fairly level with a max deflection of about 8mm in a couple of corners and the hallway. The better half has chosen a Coretec LVT click herringbone design and I’m looking to prep the rest of the floor. My plan is as follows: - Belt sand the rest of the original boards to remove cupping - Screw 5.5mm SP101 at 150mm centres (100mm at edge) to new ply and old boards (can’t go 9mm as the bifold transition is too low) - Ardex feather between all boards - Use some sort of screed or latex to bring the concrete up to level and feather into ply Where I’m getting stuck is: 1) Should I raise the low spots of the floor by taking up the old boards up and shimming joists or just feathering the low areas into the rest of the floor with screed once the 5.5mm is down? (Are there self levelling screed that you can feather to nothing?) 2) What screed/latex is best for on top of the concrete? 3) Where else have I screwed up in my plan? I know I’m probably an idiot for taking all this on but any/all help is appreciated!
Get a damp test done and change the click to a stick down. Not hearing great things about the click herringbone
I’ve been round that argument many times with the wife and completely lost! She wants the ‘v-grooved’ planks so it looks like real wood (which isn’t an option due to large dogs) and Coretec seems the best of the LVT click systems.
8mm deflection is way too much for any click system, go with a glue down most of which have a V groove, you need a Rh% test on the concrete but it will probably need a surface dpm or moisture suppressant, Ardex NA can go to 0mm and is moisture tolerant so would be my choice here for a self levelling compound if you’re coming up 6mm then 3mm screed, surface dpm then the last 2.5mm/3mm screed to finish. Sent from my iPhone using Tapatalk
Thank you. Ardex NA seems to say minimum of 3mm on the tub but I’ll take your word for it would you also use the Ardex NA on top of the plywood to level out the 8mm corners?
