Level out floor with plywood, any advices regarding what screws to use and gaps to screw them on?

Hello,

With advice from another thread I've decided to plywood the old floorboard before putting any LVP or laminate down, I was going to go with Vinyl but the so I've already bought 9mm plywood( 7 of them) so it's too late to back up from this project now, laminate or LVP I thought I'll just use them to even out the floor.

I've never done this before so it seems the general advice online is to drives screws 10cm apart on edges and 15cm gaps elsewhere on the ply.

1. I decided to use 25mm screws as thickness of floorboard+plywood is about 27mm. is this good? or should I get 30mm and make sure not to drill in to any pipes or wires .

2. Should I use 3mm or 4mm screws? or even thicker?

3. Should I use longer screws to go through over joists where they are or just forget joists and only screw it to the floorboards?

4. If I do go through joists then should I drill pilot holes first?

Thanks

Screw on 150mm centres, 10mm along edges, 4 x 25mm. Main thing is to ensure that you don't jack the plywood up off the sub floor (stand on the floor right next to where you are screwing and screw down at the highest speed possible in one go) and you leave the heads flushed (if you don't flush it first time, back the screw out and redrive it a couple of millimetres away from the original hole)

JobAndKnock said:

Screw on 150mm centres, 10mm along edges, 4 x 25mm. Main thing is to ensure that you don't jack the plywood up off the sub floor (stand on the floor right next to where you are screwing and screw down at the highest speed possible in one go) and you leave the heads flushed (if you don't flush it first time, back the screw out and redrivevit a couple of millimetres away from the original hole)

Click to expand...

Cheers mate

Use decent screws as it helps a lot

https://www.screwfix.com/p/goldscre...k-multipurpose-screws-4-x-20mm-200-pack/11192

these are decent and a great price

dazlight said:

Use decent screws as it helps a lot

https://www.screwfix.com/p/goldscre...k-multipurpose-screws-4-x-20mm-200-pack/11192

these are decent and a great price

Click to expand...

Do I need to use TurboGold ones which seem to have more grip ? double the price




or just regular Goldscrew in your link will do?

Turbo would be better if you don’t mind paying the extra