6mm plywood OR hardboard.

[skodaman007]

Hi all.Sorry 2 questions.

1.is 6mm plywood better than 6mm hardboard to give a decent base to carpets.

2.does the plywood need to be treated with water before fitting.

I will be useing 25mm annunual nails very often.

PS, this will be fitted over existing hardboard.the existing hardboard has cut and lifted in patches many times for trades folk.so in rather poor condition in many places.

Many Thanks.

 

[crazydaze]

Uplift the old hardboard and fit the 6mm ply.

 

[JohnD]

1 yes but pull up the old stuff like crazydaze says

2 no

3 decide where the pipes and cables are, before you start nailing, and chalk onto the floor

 

[skodaman007]

Thank you 2 for replys.

After looking at the existing hardboard closer it appears the damage is only confined to one place.

I would like to replace the damaged hardboard with hard board and then cover all the hardboard with 6mm ply,am i asking for trouble doing this overboard.

Thank you.

 

[crazydaze]

You are wasting your time, ply is the better levelling product, better to either repair the small area with hard board and forget ply or uplift all the hard board and replace with new 6mm ply, that's how a professional would tackle the job.

 

[Symptoms]

skoda - reconsider those 25mm annular nails. Check the thickness of your floorboards, add the thickness of your hardboard and your nails should be equal to or less than that measurement. Do this and you WILL NOT hit any pipes of cables lurking below. So use 20mm annulars if in doubt or stick with the 25s if you know there's nothing below.

 

[dazlight]

Also when fixing the plywood. You want a nail every 6 inches all over and on the joints every 4 inches.
Make sure the floor boards are solid before you start so you don't have any creaking. If the floorboards are cupped are bad condition then maybe use 9mm ply mate

 

[kjacko]

can i hijack slightly and add to the OP and ask;
i have an abundance of 25mm self-tapping bugelhead screws. Can i use these to secure my 6mm ply to my already pretty level bathroom floorboards?
Rather than buying nails, yes i know screwing will take longer, but they are sitting there doing nothing.
Floor (25mm) + ply (6mm) = 31mm
Screws = 25mm
So, even when countersunk they shouldn't poke through the bottom of the floorboards.

Any foreseeable issues with this please?

 

[crazydaze]

The length and risk is personal preference, how level the screw heads will be and how you level the finished areas needs consideration

 

[kjacko]

Well....the screw idea didn't work, so need to either buy different screws or get some nails. My compressor is elsewhere so my air nailer is out of the question.
So what's best to use, 20mm annular nails (quicker and no doubt cheaper) or screws (to avoid any creaking)?

 

[crazydaze]

Screws

 

[kjacko]

any particular ones, obviously a max of 25mm to be safe.

Will these do?
http://www.screwfix.com/p/screw-tite-prodrive-csk-4-x-25mm-pack-of-200/58439

 

[crazydaze]

Yep they would be fine

 

[JohnD]

if you're just using it to give a flat smooth surface for carpets, it doesn't need much. Tacks or big staples will do. Lots along the edges and joins.

the heads will be lost in the underlay so no need to countersink if they're only little. Some people tape over tacks and staples if they're going to lay vinyl.

 

[kjacko]

Right, thanks. Sice realising my floorboards are 18mm and thus making 25mm screws too long, i'll be buying these tonight instead.
http://www.screwfix.com/p/turbogold-countersunk-screws-3-5-x-20mm-pack-of-200/16558