Poll - What’s your preferred material for subfloor?

[Munzy]

Really interested in your thoughts on the best subfloor to go in bedrooms/hallways/landings on upper floors over the top of joists. Finished floor will be carpet over the top.

There are so many opinions and preferences on this one so thought I’d go with the majority!

I’m assuming 18mm thickness for each of the options.

 

[Ian H]

I used the P5 2400x600 t&g boards but wish I had used full sheets of ply like my Grandad did at our last house.

That’s in a loft conversion.

 

[Munzy]

I used the P5 2400x600 t&g boards but wish I had used full sheets of ply like my Grandad did at our last house.

That’s in a loft conversion.

Why would you use the full sheets over the T&G?

 

[Ian H]

They creak. I had them down loose for a bit while the roof was being done then fixed them properly after insulating the walls and floor.

My Grandad used a decent 18mm ply and they were silent.

Next time I need a carpet I plan to replace them. Although I only screwed them, didn’t glue them.

 

[JohnD]

chipboard, vom vom.

If your wife is strong enough to carry 8x4 ply up the ladder, it's preferable. You can also tighten the screws a bit more without the heads sinking in.

 

[Deleted member 174758]

They creak......

.....I only screwed them, didn’t glue them.

I think that's where your issue is. They are far, far better when glued. How did you set the tongues into the grooves? Did you use a hammer and puller bar or something heavier? What centres are your screws on?

 

[Ian H]

I screwed 3 across each board and my joists are at 400 centres so 21 screws in each.

I tapped them in using an offcut with the groove on. While they were loose they were much quieter.

 

[Deleted member 174758]

I've tended to use a sledge hammer and a piece of 4 x 2 CLS to get a tight joint, but then we always glue our joints with D4 PVA which means there is an issue with hydraulic resistance due to the the glue. We also glue to the joists. AFAIK this is the recommended method of fixing to avoid creaks