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I just purchased a new shower tray and because this one sits almost flush with the floor, I need to cut a notch in a beam for the drain. Unfortunately I purchased it before lifting the floorboards and the drain lands exactly on a beam. The beams sre 80mm wide and 110mm deep. To fit the drain I would need to cut a notch 55mm deep and 140mm long, which would seriously weaken the beam.
How would I go about adding some strengtheners to the beam? Is my required notch just too big and ill advised? I can't position the shower any other way as I don't have the space and I don't want to raise the shower as the idea was to have an almost walk in shower.
One more question for plumbers. If you plumb with PEX what do you do when you exit a dry wall and the pipe needs to be visible like for a toilet? Walking around the DIY shops here in France I haven't seen anything that looks like it would do the job and be aesthetically pleasing.
Post edited at 19:33
In reply to Phil Payne:
Don't do it.
Your joists / beams ,sound a bit light in the depth department as it is.
Although ,are you sure you're seeing the full depth of the beam.
Beams may have beam fill between ,and could be deeper than you are seeing.
Can you see the plasterboard/ plaster from the ceiling below?
Don't do it.
Your joists / beams ,sound a bit light in the depth department as it is.
Although ,are you sure you're seeing the full depth of the beam.
Beams may have beam fill between ,and could be deeper than you are seeing.
Can you see the plasterboard/ plaster from the ceiling below?
Post edited at 19:39
In reply to andymac:
I probably should call them joists and not beams as that is what they are. I'm sure that I'm seeing the whole joist as there is a suspened ceiling below it. It's an old house and the joists are 45cm apart to make up for the smaller joist size that I have.
My plan was to double up the joists either side and then add a cross piece to support the notched joist. It's too late to take the tray back and get one with a drain in a better position as I got the last model that was on clearance sale and sold as seen with no option to return it.
I probably should call them joists and not beams as that is what they are. I'm sure that I'm seeing the whole joist as there is a suspened ceiling below it. It's an old house and the joists are 45cm apart to make up for the smaller joist size that I have.
My plan was to double up the joists either side and then add a cross piece to support the notched joist. It's too late to take the tray back and get one with a drain in a better position as I got the last model that was on clearance sale and sold as seen with no option to return it.
In reply to Phil Payne:
There are lots of metal joist hangers in the DIY shops. When I decked my garden , I found these very handy, (with just a few modifications) , they could be adapted to be strengtheners, as well as supports. ( however, I guess you cannot access the bottom of the beam?)
http://www.screwfix.com/c/building-joinery/builders-metalwork/cat850192
> I just purchased a new shower tray and because this one sits almost flush with the floor, I need to cut a notch in a beam for the drain. Unfortunately I purchased it before lifting the floorboards and the drain lands exactly on a beam. The beams sre 80mm wide and 110mm deep. To fit the drain I would need to cut a notch 55mm deep and 140mm long, which would seriously weaken the beam.
There are lots of metal joist hangers in the DIY shops. When I decked my garden , I found these very handy, (with just a few modifications) , they could be adapted to be strengtheners, as well as supports. ( however, I guess you cannot access the bottom of the beam?)
http://www.screwfix.com/c/building-joinery/builders-metalwork/cat850192
In reply to Phil Payne: Hi mate you shoudnt cut a notch more than one sixth of the overall depth and not in the middle or third way of the length ,classes as structurally unsound.
In reply to Jim C:
That's exactly what I was thinking of using. There's enough space for me to put a hanger on the joist either side and then run a supporting beam directly under the notch. I have about 150mm below the joists to the suspended ceiling below.
That's exactly what I was thinking of using. There's enough space for me to put a hanger on the joist either side and then run a supporting beam directly under the notch. I have about 150mm below the joists to the suspended ceiling below.
In reply to Phil Payne: I would bolt a section of metal angle or flat bar to the beam on both sides to support the area around the notch. I am no building inspector but this should be as strong as the original joist.
HTH Davey
HTH Davey
In reply to blackcat:
I had a read of the regulations, but there must be some sort of solution to this as it must be quite common in renovation projects. It's my first time renovating a house and I think I might have taken on too much.
Already had to completely rewire the house, which wasn't planned and now discovered that all the plumbing is dodgy, so have to rip everything out and start again.
I had a read of the regulations, but there must be some sort of solution to this as it must be quite common in renovation projects. It's my first time renovating a house and I think I might have taken on too much.
Already had to completely rewire the house, which wasn't planned and now discovered that all the plumbing is dodgy, so have to rip everything out and start again.
In reply to Phil Payne:
Can you turn the tray around perhaps and miss the beam ?
Or raise the tray above floor height?
Or buy another tray with different dimensions so you miss the beam?
Or move it in its position so you miss the beam.
You cannot cut the beam by that amount as previous posters have mentioned , as it would be too weak to carry a load.
Can you turn the tray around perhaps and miss the beam ?
Or raise the tray above floor height?
Or buy another tray with different dimensions so you miss the beam?
Or move it in its position so you miss the beam.
You cannot cut the beam by that amount as previous posters have mentioned , as it would be too weak to carry a load.
In reply to Phil Payne:
Have you got scope to bring the shower out from the wall slightly ,so the waste falls between the beams.
Or could you rotate the tray 90 degrees and be inventive with your waste pipe?
Sounds like you have got the right waste .nuflow?
Edit .Sorry Rich.
Have you got scope to bring the shower out from the wall slightly ,so the waste falls between the beams.
Or could you rotate the tray 90 degrees and be inventive with your waste pipe?
Sounds like you have got the right waste .nuflow?
Edit .Sorry Rich.
Post edited at 20:01
In reply to andymac:
The waste is 450mm from both edges, so turning it 90 degrees wouldn't help. Moving it out from the wall doesn't work as I would still need a notch 40mm deep and 40mm wide for the drain and would massively complicate the rest of the shower installation and look weird.
The shower tray was €350 and I can't take it back, so determined to make it work somehow. Just hoping for someone to suggest a better way to do it than my current plan.
The waste is 450mm from both edges, so turning it 90 degrees wouldn't help. Moving it out from the wall doesn't work as I would still need a notch 40mm deep and 40mm wide for the drain and would massively complicate the rest of the shower installation and look weird.
The shower tray was €350 and I can't take it back, so determined to make it work somehow. Just hoping for someone to suggest a better way to do it than my current plan.
In reply to Phil Payne:
No idea if it would meet regulations as such but I would buy 2x1m lengths of 50x25mm steel U channel and bolt through both sides of the steel and the original beam so the load at that point will be shared between the remaining beam and the steel.
Another option would be steel plate that you bolt to the sides with the same cut out for the trap.
No idea if it would meet regulations as such but I would buy 2x1m lengths of 50x25mm steel U channel and bolt through both sides of the steel and the original beam so the load at that point will be shared between the remaining beam and the steel.
Another option would be steel plate that you bolt to the sides with the same cut out for the trap.
In reply to stewieb:
It's my house and nobody is going to come inspecting so I don't really need it to conform, I just need it to work and not fall apart anytime soon. I plan to live in it and not rent it or sell it on, so not trying to hide something to make a quick profit.
It's my house and nobody is going to come inspecting so I don't really need it to conform, I just need it to work and not fall apart anytime soon. I plan to live in it and not rent it or sell it on, so not trying to hide something to make a quick profit.
In reply to Phil Payne:
Is this first floor or ground floor? I'm very surprised that the joists are so small in either case!
Don't bother trying to trim out the joists, it's a hell of a lot of work just for a shower tray. And definitely don't try to notch!
Common practice is to sit it on a plinth of 4"x2" timber then tile from floor to tray.
Is this first floor or ground floor? I'm very surprised that the joists are so small in either case!
Don't bother trying to trim out the joists, it's a hell of a lot of work just for a shower tray. And definitely don't try to notch!
Common practice is to sit it on a plinth of 4"x2" timber then tile from floor to tray.
In reply to Phil Payne:
If it was me ,and there was space beneath ( you mention a suspended ceiling ) ,I would try and get at least a 3x2 under the existing beams.
3x2 would only have to be about 1 m long ,and would run at right angles to the beams .
Fix at each end using a decent joist hanger ( with screws)
How far away from a wall head are you with your shower position?
If it was me ,and there was space beneath ( you mention a suspended ceiling ) ,I would try and get at least a 3x2 under the existing beams.
3x2 would only have to be about 1 m long ,and would run at right angles to the beams .
Fix at each end using a decent joist hanger ( with screws)
How far away from a wall head are you with your shower position?
Presumably you are clear on one side of the joist?
Patch the joist with a new piece of wood on the clear side. Dimension of the splint should be equivalent to the joist (marginally smaller to fit is ok).
Try to get as much length as possible in ideally a couple of feet at least each side of the joint. Tack together with full length 6mm or thicker screws in a zigzag pattern 1/3 from the top, 1/3 from the bottom every 100mm - you'll benefit from drilling pilot holes. If one side of the notch is close to a wall use a joist hanger on the end of the splint.
Patch the joist with a new piece of wood on the clear side. Dimension of the splint should be equivalent to the joist (marginally smaller to fit is ok).
Try to get as much length as possible in ideally a couple of feet at least each side of the joint. Tack together with full length 6mm or thicker screws in a zigzag pattern 1/3 from the top, 1/3 from the bottom every 100mm - you'll benefit from drilling pilot holes. If one side of the notch is close to a wall use a joist hanger on the end of the splint.
In reply to Phil Payne:
What happened to the original ceiling below it? I'd have thought you should be seeing that from above, not a suspended ceiling even further down.
That doesn't sound wide to me, modern joists are generally at 400mm c/c, so what you have is thick, shallow joists at wider centres than modern ones. Unfortunately, it's the depth that gives you the strength, not the width.
What you'd normally do in these circumstances is called bridling a joist. It's pretty much as you describe: beef up the joists on either side and span across, with each exposed face the cut joist (ie. where your outlet wants to be) fixed onto these new cross members.
If I were you, I'd raise the tray and forget the idea of notching. And next time, do the prep work first to see what you're dealing with, then buy the correct tray to suit the site conditions
Good luck...but don't simply notch the joist 55mm and hope it'll be alright.
> I probably should call them joists and not beams as that is what they are. I'm sure that I'm seeing the whole joist as there is a suspened ceiling below it.
What happened to the original ceiling below it? I'd have thought you should be seeing that from above, not a suspended ceiling even further down.
> It's an old house and the joists are 45cm apart to make up for the smaller joist size that I have.
That doesn't sound wide to me, modern joists are generally at 400mm c/c, so what you have is thick, shallow joists at wider centres than modern ones. Unfortunately, it's the depth that gives you the strength, not the width.
> My plan was to double up the joists either side and then add a cross piece to support the notched joist.
What you'd normally do in these circumstances is called bridling a joist. It's pretty much as you describe: beef up the joists on either side and span across, with each exposed face the cut joist (ie. where your outlet wants to be) fixed onto these new cross members.
If I were you, I'd raise the tray and forget the idea of notching. And next time, do the prep work first to see what you're dealing with, then buy the correct tray to suit the site conditions
Good luck...but don't simply notch the joist 55mm and hope it'll be alright.
In reply to mwr72:
Several people have mentioned this, but from my experience of renovating old French properties I would guess that the joists are hardwood.
This and the close centres (40 or 45cm) usually does the trick in stopping the upper floor landing on the floor below
It does however mean that notching, or even drilling through for pipes / conduit is never really an easy option as there just isn't the same volume of timber as with a nice chunky 170mm softwood joist.
> Is this first floor or ground floor? I'm very surprised that the joists are so small in either case!
Several people have mentioned this, but from my experience of renovating old French properties I would guess that the joists are hardwood.
This and the close centres (40 or 45cm) usually does the trick in stopping the upper floor landing on the floor below
It does however mean that notching, or even drilling through for pipes / conduit is never really an easy option as there just isn't the same volume of timber as with a nice chunky 170mm softwood joist.
In reply to andymac:
No idea what you mean by wall head, but the shower tray is 1200x900 and is going to be flush to the outside wall and about 60mm (dry wall thickness) from the internal supporting wall.
There's definitely enough space to get a support under the joist, probably a 3x2 would fit, hung off the joists either side. This was my first plan, together with some additional steel bolted to the joist to strengthen it. I probably need a picture to explain it better, but I'm not at the house now, so can't just go and take one.
No idea what you mean by wall head, but the shower tray is 1200x900 and is going to be flush to the outside wall and about 60mm (dry wall thickness) from the internal supporting wall.
There's definitely enough space to get a support under the joist, probably a 3x2 would fit, hung off the joists either side. This was my first plan, together with some additional steel bolted to the joist to strengthen it. I probably need a picture to explain it better, but I'm not at the house now, so can't just go and take one.
In reply to mwr72:
Not sure about the OP, but in my bathroom, I was height restricted, and whilst raising it would have helped my flow angle, the ceiling sloped down and stopped me raising it. If there is no restriction in height, that then is a good solution.
> Common practice is to sit it on a plinth of 4"x2" timber then tile from floor to tray.
Not sure about the OP, but in my bathroom, I was height restricted, and whilst raising it would have helped my flow angle, the ceiling sloped down and stopped me raising it. If there is no restriction in height, that then is a good solution.
In reply to Fraser:
You're completely right about the prior planning. I did have a quick measure before buying they tray as that was a worry. Stupidly I forgot to take into account the width of the dry wall that I'm putting in. Doh!
I am however just going to press on and cut a notch out and then go over the top with strengthening all around the notch. I've already delayed doing anything for a week while I try to come up with another solution, but I'm running out of time as I have someone coming in 3 weeks to fit a new septic tank and the plumbing has to be ready before then.
You're completely right about the prior planning. I did have a quick measure before buying they tray as that was a worry. Stupidly I forgot to take into account the width of the dry wall that I'm putting in. Doh!
I am however just going to press on and cut a notch out and then go over the top with strengthening all around the notch. I've already delayed doing anything for a week while I try to come up with another solution, but I'm running out of time as I have someone coming in 3 weeks to fit a new septic tank and the plumbing has to be ready before then.
In reply to Phil Payne:
Heh, hindsight is always 20-20! As a compromise, you could consider raising it only an inch or so and reduce the depth of the notch, but still strengthened however you choose to do so.
Heh, hindsight is always 20-20! As a compromise, you could consider raising it only an inch or so and reduce the depth of the notch, but still strengthened however you choose to do so.
In reply to Phil Payne:
If you have the headroom then why not save yourself a headache and sit it on a plinth?
>
> I am however just going to press on and cut a notch out and then go over the top with strengthening all around the notch.
If you have the headroom then why not save yourself a headache and sit it on a plinth?
In reply to mwr72:
Because I bought a really nice low profile granite effect tray to create a walk in shower that's flush with the floor.
Because I bought a really nice low profile granite effect tray to create a walk in shower that's flush with the floor.
In reply to Phil Payne:
put a picture up on here of the joists and what you want to do,then we can give you some help
put a picture up on here of the joists and what you want to do,then we can give you some help
In reply to windjammer:
I'd love to employ a plumber, but of all the ones we had come round to give us a quote, only one actually gave us a quote, which was extortionate and he wasn't really a plumber, more of a handyman.
I'd love to employ a plumber, but of all the ones we had come round to give us a quote, only one actually gave us a quote, which was extortionate and he wasn't really a plumber, more of a handyman.
In reply to Phil Payne:Phil you have bought a nice tray but wrong type for your floor detail.get advice of a local builder if you can before you do something that could not saying would but could end up costing you even more cash.
In reply to Phil Payne:
I would cut out the section that is in the way as far back as you need to go and then using a new piece of timber fit it into the gap at right angles. Nail it to the joists either side and on the cut section. So effectively making a square in which the drain can go down. And the joist that has been cut is now supported by the 2 joists on either side of it.
I would cut out the section that is in the way as far back as you need to go and then using a new piece of timber fit it into the gap at right angles. Nail it to the joists either side and on the cut section. So effectively making a square in which the drain can go down. And the joist that has been cut is now supported by the 2 joists on either side of it.
In reply to blackcat:
What do you mean by that? The old shower was supported by a 8 inch concrete thing that weighed about 150kg. I'm certainly not worried that the joists won't take the weight of my new shower tray, which is somewhere around 75kg.
Thinking about it a but more, I might get away with a slightly smaller notch that doesn't go across the entire width of the joist and is only 75mm long instead of 140mm by being a but more creative with the routing.
What do you mean by that? The old shower was supported by a 8 inch concrete thing that weighed about 150kg. I'm certainly not worried that the joists won't take the weight of my new shower tray, which is somewhere around 75kg.
Thinking about it a but more, I might get away with a slightly smaller notch that doesn't go across the entire width of the joist and is only 75mm long instead of 140mm by being a but more creative with the routing.
In reply to Phil Payne:
I don't know about buildings but I do know about structural engineering.
Just to reinforce what's already been said, the strength of a beam in bending, which is what beams do, is proportional to the third power of it's depth. That means that if you reduce the depth by half you reduce the strength by a factor of 8. Probably not a good idea.
If you really want to go for it get a couple of substantial steel plates, maybe 5 mm thick and 150mm longer than the cut out at each end and bolt them on either side of the beam drilling right through the beam so each bolt hollds both plates and the beam together. You'd probably want to have about six bolts along the length, three near the top of the plate and three near the bottom in a zig zag.
Good luck.
I don't know about buildings but I do know about structural engineering.
Just to reinforce what's already been said, the strength of a beam in bending, which is what beams do, is proportional to the third power of it's depth. That means that if you reduce the depth by half you reduce the strength by a factor of 8. Probably not a good idea.
If you really want to go for it get a couple of substantial steel plates, maybe 5 mm thick and 150mm longer than the cut out at each end and bolt them on either side of the beam drilling right through the beam so each bolt hollds both plates and the beam together. You'd probably want to have about six bolts along the length, three near the top of the plate and three near the bottom in a zig zag.
Good luck.
In reply to Phil Payne:
Sounds like very typical floor joist size and spacing for old French houses to me - and a typical 'challenge' to overcome when renovating old French houses! These French floors are also frequently a bit more bouncy than you'd be used to! How near to a wall supporting one end of the joists is the notch (this is probably what someone earlier meant by as wall head)? As others have said, beefing up adjacent joists and running a support under the notch and across into joist hangers on adjacent joists should work.
For the PEX installation you can either switch to copper pipe (connectors with solder joint to pipe on one end, screw on connection for PEX fitting on other end) or you can also get metal plate fittings which screw onto the drywall with a PEX connection on the back, leaving a neat male thread against the wall, you then use one of the braided silver 'flexies' to connect to your toilet. The twin ones with two connections perfectly spaced for standard bath/shower hot/cold connections are useful (if expensive).
Sounds like very typical floor joist size and spacing for old French houses to me - and a typical 'challenge' to overcome when renovating old French houses! These French floors are also frequently a bit more bouncy than you'd be used to! How near to a wall supporting one end of the joists is the notch (this is probably what someone earlier meant by as wall head)? As others have said, beefing up adjacent joists and running a support under the notch and across into joist hangers on adjacent joists should work.
For the PEX installation you can either switch to copper pipe (connectors with solder joint to pipe on one end, screw on connection for PEX fitting on other end) or you can also get metal plate fittings which screw onto the drywall with a PEX connection on the back, leaving a neat male thread against the wall, you then use one of the braided silver 'flexies' to connect to your toilet. The twin ones with two connections perfectly spaced for standard bath/shower hot/cold connections are useful (if expensive).
In reply to Phil Payne:
If you're doubling up on joists by bolting a new one to the side of the existing one, then you're supposed to use one of those evil toothed washers inbetween the joists for each bolt location. They seem to make a big difference in the solidity (I've done my kitchen ceiling joists that way) following advice from a friendly civil engineer with access to joist size calculation software ).
What about the waste pipe, are you going to have to cut any more joists?
You will find this useful:-
http://www.dfpni.gov.uk/d.pdf
If you're doubling up on joists by bolting a new one to the side of the existing one, then you're supposed to use one of those evil toothed washers inbetween the joists for each bolt location. They seem to make a big difference in the solidity (I've done my kitchen ceiling joists that way) following advice from a friendly civil engineer with access to joist size calculation software ).
What about the waste pipe, are you going to have to cut any more joists?
You will find this useful:-
http://www.dfpni.gov.uk/d.pdf
In reply to Toerag:
I found a solution. I'm just going to slide the shower tray into the wall by 5cm and then tile down to it. Hopefully it won't look too rubbish and I don't think anyone would notice that the shower tray is 115cm long and not 120cm.
I found a solution. I'm just going to slide the shower tray into the wall by 5cm and then tile down to it. Hopefully it won't look too rubbish and I don't think anyone would notice that the shower tray is 115cm long and not 120cm.
In reply to Phil Payne:
Drop a new joist (or two) in close to the cut one but clearing the drain. Or double up the two joists either side of the cut one then frame around the cut. Or if there is plenty of space under the cut joist drop in a deeper joist so the cut is less severe. There are loads of reasonable options if it doesn't have to comply with regs.
jk
> It's my house and nobody is going to come inspecting so I don't really need it to conform, I just need it to work and not fall apart anytime soon. I plan to live in it and not rent it or sell it on, so not trying to hide something to make a quick profit.
Drop a new joist (or two) in close to the cut one but clearing the drain. Or double up the two joists either side of the cut one then frame around the cut. Or if there is plenty of space under the cut joist drop in a deeper joist so the cut is less severe. There are loads of reasonable options if it doesn't have to comply with regs.
jk
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