OSB vs. Marine Ply for flooring?

The difference in price between marine ply and OSB is huge. Marine ply is about 2.5 times the price.

I need about 30 sheets to cover all the floors of our three-bed semi, upstairs and downstairs.

We will then lay a mixture of semi solid and tile floors.

I am aware that, for the tiling areas, the wood underfloor needs one screw every eight inches. I will also run the central heating system for a while before laying the floor. Finally, I will use levelling compound, if necessary, and lay the tiles using flexible adhesive.

What I want to know is, can I do this using OSB?

Thanks.

D.

The simple answer is yes, OSB can be tiled over. You can check out Louisiana Pacific's website for more info on OSB. Where OSB is being tiled over I would use a scews at 150mm (6") spacings. If you were worried about movement in a bathroom/ ensuite floor you could run a bead of Gunoprene or Dap panel adhesive along the joists before screwing down the panels, although the glue is messy. You refer to "marine ply" in your message I presume you mean standard WBP (weather and boil proof) plywood which is roughly €35 per 8'x 4' sheet, marine ply on the other hand is 2 or three times this and would be an overkill for this application and a waste of good timber........

Carpenter,

Thanks for that.

For the record, best price I can get for 31 sheets of OSB is €660.

Best price for marine ply is €1600.

Both include VAT and delivery.

I too thought that marine ply was overkill, which was why I made a few enquiries.

Another question...........

I am using solid oak framed internal doors with oak laminated MDF panels. They look fantastic (Shaker pattern) and feel solid and heavy.

I am also using 6" solid oak skirting. It is flat with just a micro bevel on the upper edge. It's expensive, €3 a foot, but I'll only be buying it once! ;-)

My problem is the door frames. If I go solid oak, they cost a small fortune. If I go MDF oak laminated, they are much cheaper. But, they are only available in two widths 131mm and 108mm. Unfortunately, our house has door frames of varying widths. Six are 108mm and one is 131mm. But, four are wider.

We intend to cover the oak in satin varnish, so everything will be visible. What are my options? It is Heiton Buckley who can only provide the readymade frames in two sizes. Is there anyone who can provide them in wider fittings?

It seems a bit odd that frames are not available in a greater range of sizes.

Thanks.

D.

Dinarius,

Can i ask you a quick question..

I am using solid oak framed internal doors with oak laminated MDF panels. They look fantastic (Shaker pattern) and feel solid and heavy.

Click to expand...

Where did you source your doors and what price are they standing you?

I intend to put in oak doors in my house and have gone with white deal frames which will then have an oak slip, oak door stop & achitrave put on to cover the frame.

laragh said:

Where did you source your doors and what price are they standing you.

Click to expand...

Heiton Buckley, Robinhood Industrial Estate.

€103.31 plus VAT.

D.

In relation to your query regarding door frame sizes, they come in two standard sizes to suit either blockwork or timber stud walls, as follows:

Blockwork is 100mm thick (4"), add 12mm or 15mm each face for render and skimcoat, adds up to 125-130mm

Timber studs are 75mm thick, add on 12mm or 15mm each face for plasterboard and skimcoat, adds up to 100- 105mm.

You could buy some planed oak slips to fix on the visible edge of the frame, setting back from the edge by a few millimetres to create a shadowline. When stained and varnished no one will be any the wiser. This is done all the time in older buildings and restoration work where wall thicknesses and door surrounds vary. If you had access to a table saw and thicknesser you could buy a couple of lengths of 4x 2 oak, rip down to size and thickness to the dimensions you need, wouldn't cost much, just a little bit of work.

Back to the question - which is better ?

3/4 ply or OSB, it is to used to floor on top of 9x2 joists.

Ply is a superior product to OSB in my honest opinion (thus the higher cost) but OSB may be more than sufficient for the application you require, unless you anticipate a lot of traffic on the floor before you tile it; in which case I'd use ply as OSB will break up if heavily trafficked.

Hello

Thanks for the reply - I need 50 sheets of 8x4. I think I will go for the 3/4 ply - its 25 euro a sheet and osb is around 18. Do you think nail gunning (paslode) it down would be OK - or do I need to screw it down.

If tiling over this I would glue and nail down or else screw fix only. Nail heads can "pop" due to timber shrinkage and the lack of a thread on the shank. (ok the Paslode have a annular shank, but this is not as effective as a screw thread for keeping timber in place.) Just my view, others may disagree...

Why not use tounge and grove chipboard flooring sheets.They are 8x2foot in size and cost about €8 per sheet.these boards are much better for flooring as the tounge and groove makes sure they dont move.you can lay timber floors on them and for tiling all you need is 6mm ply screw fixed every 6inch.I use this on all our projects and have never had a problem.marine ply is too expensive and osb is from experience a "cheap job "..