To ply or not to ply bathroom floor for vinyl sheet

[JP_]

I have 18mm green chipboard on my bathroom floor. Only 2 joins (room is 2.3m wide) and all pretty flat and smooth. Friend (a plumber and bathroom fitter) said that I just need to tape over the joins to avoid risk of lines appearing in vinyl sheet.

Previously, floor fitters have suggested putting ply down.

Just been quoted £60 for vinyl, £40 to fit, plus £80 if i want to ply.

Do I need ply? One suggestion was that if the floor needed to come up, it's easier to remove the ply than tear glued vinyl off chipboard (could cause damage). So that makes some sense.

How is ply fitted normally? Tempted to do this part myself if I'm going to save some of that £80. Is is screwed? I guess not glued, as that would then have the same problem when removing ...

 

[stem]

Having had to take up my bathroom floor to access some pipework previously, I was then reluctant to fit ply which would make access to the floorboards difficult, especially as it would have gone underneath the WC pan and sink pedestal. So I fitted hardboard instead. I found this easier to cut it and fit it around the WC / sink pedestal / pipes and as it is semi flexible made it easier for installation. I just tacked down two of the edges that were at right angles to each other to allow the other edges to move for expansion without creating bulges. Then if I did need to take up part of it, it can be cut with a sharp knife. Been down for 10 years now without any issues, although I suppose a lot will depend upon how flat the subfloor is to start with.

 

[JP_]

that makes sense, almost. Doesn't the hardboard have edges in the room like the floorboards? Or is this more about not going straight onto the floor?
Floor is flat, so that is not a problem.

 

[foxhole]

No need for anything on the floor , vinyl is easily removed from chipboard without damage.

 

[JP_]

Cheers, that is good to know!

 

[stem]

@foxhole is right. I missed that you said that you had chipboard down.

Covering with ply is normally only proposed when there are floor boards (or uneven floors) to prevent the vinyl showing up the lines between the floor boards as they move against each other.

Regarding the edges "in the room like the floorboards" the hardboard / plywood join would be positioned in the centre of a floorboard so the two parts wouldn't move independently of each other. But it doesn't matter in your case. As you have chipboard down all you need to do is make sure that any joins between the chipboard are secure.

 

[JP_]

Great. Next question ... when should I put the skirting board down?
I know normally first, but the basin vanity unit will go in on top of the floor, so unless I put the unit it, add skirting, then remove it again, I'm going to have to do the skirting after.

Is it best I put the unit in for the skirting then remove?

 

[crazydaze]

For Vinyl Sheet, you only need to fit 4mm pre-wet hardboard, you don't need to ply.

It would be recommended to fit the skirtings first then hardboard, then fit the vinyl.

You can lay over the chipboard with no prep but as a profesional, this would leave an installer or retailer liable if you were unhappy with any ridge showing through the vinyl by way of a lump or visual showing through the vinyl. (if you hold a piece of vinyl to a light, youll see it's quite see-through and it is this trait that means lines and markings.discolouration or pre-existing flooring that it is laid over can show through after installation).