Should I put additional blocks under the bath legs

[tpb1975]

Just had an extension done and the builder put in a bathroom. He mentioned early in the build that he would put two layers of flooring under the bath legs. In the end the legs are just on the floor, no doubled up boards.

I've got some 6x2, 4x2 and 18mm external ply hanging around. Is it worth putting any under the legs, or are the feet typically big enough on baths?

I was thinking 18mm external ply, as doesn't seem to compress as much as the wood. I can't screw it into the floor as the bath is already in place. So it would be a case of raising each leg, sliding a bit under then dropping again.

If it is standard to put something under the legs, if so typically what sort of dimensions? Or is it just not really necessary?

Thanks for any tips.

 

[Newboy]

What is the floor made of ?

 

[OwainDIYer]

I would deffo put some plank or something underneath to spread the load. Most flooring isn't up to very high point loads.

But as the builder said he would do this why aren;t you asking him back to do the job properly? (including retiling etc if necessary)

 

[tpb1975]

What is the floor made of ?

It's the new 22mm large sheets of water resistant flooring that they use now. In my last house I used to have a metal bath. It was just on legs on tongue n grove wood floor. Tried to take the bath out when doing a refurb. Two of us couldn't shift it. In the end I cut it in half with a grinder. Given the weight of that, I'm wondering if a fibre glass bath needs the load spread.

Wouldn't want to argue with the guys who got it in there in the first place

 

[Tipper]

It's not the weight of the bath that is the issue, it's the water that's in it!

 

[tpb1975]

Yeah at 1kg a litre of water, I guess you only need 80l to get the weight of a person.

I might put a 100x100mm 18mm Ply under each leg.

 

[Newboy]

Ideally a piece of 4x2 spanning across 2 joists

 

[Madrab]

The old tongue and groove floorboards @ 22+ mm thick is very tough and durable and are fine at handling high point loading. The new water resistant compressed chipboard isn't as durable especially in damp areas. Ideally a piece of your marine ply to spread the load of each leg for a bath full of water and a person in it, would be ideal.

If you still have snagging to go with the builders get them to do it?

 

[tpb1975]

As the bath is already in place, I'll probably use 18mm exterior ply for the legs closest to the wall. I can no longer get to the bolt at the top of the leg to bring it high enough. Might use 2x4 for the front legs or just more of the same exterior ply. Seems very strong, looks like it's made out of hard wood. Certainly looks less likely to compress with weight on it.

Unfortunately or fortunately the builder has gone. He built an extension and pretty much ballsed up every job on it. Initially I thought it was me but when I started pointing stuff out to building control, they mostly agreed. They pretty much said it's not the worse job but there are issues to be resolved.

Both the wife and myself are glad to see the back of him. Unfortunately I'm left with possibly thousands of pounds of repairs. Bit gutted, ruins a home (not just a house) in many ways.

 

[longdogs]

A bath should always have some kind of support under the legs to spread the load.

If you do two legs at a time the bath will probably just hang in position for you to slide some board under. But make sure they are re-tightened to the same level as it could cause leaks if the sealant is under pressure.

 

[Madrab]

As the bath is already in place, I'll probably use 18mm exterior ply for the legs closest to the wall. It Seems very strong, looks like it's made out of hard wood. Certainly looks less likely to compress with weight on it.

Your exterior ply, if it is exterior (hardwood or marine) should be stamped as such, (WBP) hardwood core and exterior, at 18mm that should be plenty fine for what you need it for.

 

[tpb1975]

Balls... I went to Travis Perkins and asked for an external ply. He took me to some ply so I just ordered it.

Looking at the label it's Structural Ply (for use in Walls, Floors & Roofs) Adhesive is MUF+PF. Requires treatment for external use. It's getting used as a bath panel to tile. I was thinking about putting a couple of diluted coats of PVA on it anyway. Will it be OK? If not, that's £30 down the tubes.

The builder used 18mm Plywood for the layboards in the loft. No markings on them but they look slightly different. He did say they were WBP. About 9 thinner layers and a darker exterior than what I've got. Problem with the stuff in the loft is it's almost always wet. He put down GRP stuff as a valley rather than lead but didn't put anything under it. So where this thin plastic makes contact with the breathable felt, which in turn makes contact with the layboard is always wet. I guess it's a really cold patch. Just had a look around the loft and it's still a little wet even at a relatively warm 4C. Guess it's just not warm enough to dry out.

 

[JacktheFitter]

All hilarious......... no need to place anything under your bath legs. The flooring itself spreads the load over existing floor joists., adding anything else would be pointless.

 

[longdogs]

All hilarious......... no need to place anything under your bath legs. The flooring itself spreads the load over existing floor joists., adding anything else would be pointless.

The chances are, it will be fine, but chipboard & water is not a good mix and I have seen bath legs poking through chipboard floors because the weight is on one point.

 

[Madrab]

All hilarious......... no need to place anything under your bath legs. The flooring itself spreads the load over existing floor joists., adding anything else would be pointless.

Have had to refit 3 baths up to now that were sat on the P5 chipboard without spread support due to flooring getting damp from the panel side and sagging due to the weight. One had to have sections replaced due to a foot breaking through 22mm chipboard when it was damp. A builder recently mentioned that lot of their new builds only use standard P5 everywhere rather than P5 PVC Wet Coat designed for wet areas, due to the costs.

Not every one has trouble of course, as it all depends on the flooring and sealing I guess but P5 can have issues with point loading if it gets damp.