Floor loading for bath

[Marineboy]

I'm about to install a bath in the bathroom in our Victorian house - I removed the old grotty one several years back to replace with a shower cubicle, and I am only now getting round to putting one back. This involves knocking down a stud wall so will give me a considerably larger room.

We are looking at a mid-size roll top bath, capacity 190l. It will go 20mm or so away from the side wall, its length perpendicular to the joists. These are 170 x 60 at 410 centres, overlaid with 22mm floorboards.

2 questions - will the floor support the weight of the bath? And, should I replace the floorboards under the ball feet with a sheet of ply?

Cheers.

 

[Brandlin]

I'll leave the structural advice for others with more expertise.

However the thing to remember is that 190l of water weights 190kg... so 2 big blokes. I'm pretty sure you've never worried about the floor loading if you say had a few friends round and three people stood in the same room talking to each other?

170 deep for a floor joist does seem a little light? whats the span? As to ply/ floorboards, a tongued and grooved floorboard properly installed is going to be just as strong as ply, probably stronger. Why butcher the integrity of the floorboards to install a patch?

Also, every time your wife gets in the bath you'll be thinking... "thats my wife, with 2 big blokes, in the bath".

 

[MikeG.]

If the joists are spanning from where the wall is (ie the wall upstairs that the bath is near is directly above the wall that supports the joists), and assuming the joists aren't weakened, then yep, that's a seriously strong floor. If the floorboards are OK then they won't need replacing or reinforcing, but you could rest the bath on a spreader, such as a piece of 4x1 laid on top of the existing floorboards, just to be absolutely certain. Obviously that only applies if you are having a bath panel.

 

[owen]

Depends on the span of the joists?
Unless I've missed that part?

 

[Marineboy]

Thanks all for those prompt replies. Yes Mike, the wall is the side wall of the house, and the span is 2400mm. The bath is supported on claw feet so a spreader on top of the boards is not an option, but as the boards are slightly uneven I think I will drop in a piece of ply even though it is not needed for strength.

 

[Trainee neophyte]

Thanks all for those prompt replies. Yes Mike, the wall is the side wall of the house, and the span is 2400mm. The bath is supported on claw feet so a spreader on top of the boards is not an option, but as the boards are slightly uneven I think I will drop in a piece of ply even though it is not needed for strength.

You could make a feature of the spreader - put the bath on a plinth for extra sumptuousness:

Of course, those two big blokes may bang their heads on the ceiling getting in and out with your wife. As it were...

 

[Marineboy]

That’s nice - but unfortunately I don’t have the room for that.

 

[MikeK]

My sister and her husband learned the hard way to present all of the information when asking for advice. They were remodeling the master bedroom in the 100-year old farm house, which included adding a bath to the small en suite that had only a sink, toilet, and shower. The previous owners of the house added the en suite during their remodeling adventure.

My sister's advisors said the wooden floor and joists would easily take the load of the bath, but they were thinking about a modern bath with a continuous base around the perimeter. Had she told them she was installing an old iron claw-foot bath, I'm confident they would have advised her differently. The bath was installed parallel to the flooring joists and perpendicular to the six-inch wide pine flooring.

The two feet adjacent to the wall were close to a joist. The two feet on the other side, towards the middle of the bathroom, were between two joists. The flooring did not hold the point loads of the two feet in the middle of the bathroom and punched through the pine flooring the first time she used it. In addition to the nearly full tub spilling a lot of water when it tilted, the incident also cracked the hot and cold water pipes, which resulted in her bathroom resembling a U-boat that had been hit.

The cleanup and repairs were expensive, and in the end she got rid of the claw-foot bathtub and installed a modern tub.

 

[Phil Pascoe]

I had a 1200mm corner bath in my old house and I put the feet in steel channels spanning the joists - the joists were more than capable, but the flooring wasn't. This maybe isn't the best of solutions when everything is visible, though.

 

[Marineboy]

My sister and her husband learned the hard to present all of the information when asking for advice. They were remodeling the master bedroom in the 100-year old farm house, which included adding a bath to the small en suite that had only a sink, toilet, and shower. The previous owners of the house added the en suite during their remodeling adventure.

My sister's advisors said the wooden floor and joists would easily take the load of the bath, but they were thinking about a modern bath with a continuous base around the perimeter. Had she told them she was installing an old iron claw-foot bath, I'm confident they would have advised her differently. The bath was installed parallel to the flooring joists and perpendicular to the six-inch wide pine flooring.

The two feet adjacent to the wall were close to a joist. The two feet on the other side, towards the middle of the bathroom, were between two joists. The flooring did not hold the point loads of the two feet in the middle of the bathroom and punched through the pine flooring the first time she used it. In addition to the nearly full tub spilling a lot of water when it tilted, the incident also cracked the hot and cold water pipes, which resulted in her bathroom resembling a U-boat that had been hit.

The cleanup and repairs were expensive, and in the end she got rid of the claw-foot bathtub and installed a modern tub.

That would have been a shock!