Cutting 50mm holes in joists

[Taylortwocities]

Hope you can help/reassure me.

I need to run a drain from new shower area and the (40mm) waste will need to go through three joists to get to where the soil stack is located.

The joists measure 7½" x 1¾". The joists sit on a steel. See pic
I need to cut something like 50mm holes to run the waste. The holes would be about be near the top of the first joist and the last one would be near the centre - to allow a proper fall for the water.

Would I need to provide additional support for the joist (I'm thinking about lengths of 2x4 bolted to the bottom of the joist under each hole).
SHould I run the pipe near the end of the joists (ie over the steel?)

Thanks for your advice.



View media item 43196

 

[crashndie]

dont cut that much out mate i wont go deeper than 25mm, id use a foot pack on the shower tray and rn the waste on the skirting board then to you stack with a strap on boss

 

[noseall]

One of the reasons people have a shower tray is it makes access to bathe easy.
Then some thoughtless and lazy fitter comes along and raises it off the floor three inches!

Have you thought about dropping the waste into the room below then boxing it in along side that steel beam?

As the above poster has stated, you really can not consider cutting that amount out of 7.5" joists.

Raised shower trays look awful and should be confined to cheap hotel rooms.

 

[crashndie]

its not a case of lazy fitters its a case fitting them with in building regs rather than chopping 3/4 of a joist out 3" is hardly an accessible problem now is it ? i mean if you cant step up 3" how do get up the stairs to a bathroom

 

[big-all]

what is the span and centers if it less than somewhere about 8ft you may be ok

 

[mointainwalker]

3" is hardly an accessible problem now is it

No, but it looks bloody horrible.

 

[Nige F]

SHould I run the pipe near the end of the joists (ie over the steel?)

[]

Yes , and could you drill a 45mm hole , plus what big - all said

 

[Taylortwocities]

Thanks for the input to date.

Some updates. The three joists concerned are 14" and 18" apart. Span is 12ft.

Re the shower area. It is not a shower tray its a wet deck. One of these
http://www.vesta-bathroomsonline.co.uk/novellini-wet-floor-kit-4-1500-x-900-nwfkit4-820-p.asp
The drain trap will be set level with the top of the joist so the 40mm drain pipe will run basically from just below the top of the joist down to wherever the plumber can get a strap on boss on the soil pipe.

So, I am hoping that I'll be OK to cut those holes in the joists above the steel. The wall in the picture above the steel is just stud, and not load-bearing.

Thanks again for your guidance.

 

[SimonH2]

3" is hardly an accessible problem now is it ? i mean if you cant step up 3" how do get up the stairs to a bathroom

It is for a lot of people, and they get up and down stairs with the stairlift.

There's what looks like good money for some outfits who sell low-entry shower cubicles. The house I bought had a stairlift (weighed in nicely with the amount of ally in it ) and a shower cubicle that has less than a 2" lip to it. The invoice etc were in the pack of documents I got, and it cost the previous owner (an elderly widow) £6 1/2k

Actually, while I hesitate to suggest it, the shower cubicle is fitted with a Phlexiflow pump. This allows the use of 1/2" pipe for the drain as it sucks (rather noisily) the water from the trap. Also flipping expensive for what it is.