Underfloor Drain

[alanthomaswatson]

Morning

Planning out a garage conversion and trying to figure out drainage for an en suite.

The en suite will have a shower, toilet and sink. I assumed that we would have to pump the waste as the stack is 9m away but we actually have a 150mm void under the floor. All current outlets discharge through the floor and connect to the stack under the floor.

With 150mm over 9m, this gives a fall of 1:60 so seems to be doable?

Any thoughts/ advice?

Thanks

Alan

 

[muggles]

You're now allowing for the diameter of your pipe in your calculations. If you put a 50mm waste in, the max fall you can achieve is 100mm over the run. Worth noting though that Building Regs say the max run on a 50mm waste is four metres. Max run on 110mm waste is six metres. The recommended fall on either is 44mm per metre, with 18mm per metre as the minimum. I think a macerator pump is your only option here

 

[Hugh Jaleak]

Just realised, you your distance is further than the 6m allowed under the regs. Teach me to read things properly! Is there an option for a direct connection to the drain somewhere?

 

[John D v2.0]

there's no need to use the existing stack if it's so far away. Maybe pumping will work,, but I'd always prefer to go downhill anouther way if possible. You can connect direct to the drains without a ventilated stack if it's at ground level and the drains are not too deep. Or use an AAV if necessary, which would be better than a pump.

 

[alanthomaswatson]

Thanks all - never thought about the maximum waste run.

There is an option for a new drainage run but this would mean lifting up the newly block paved driveway for most of its length.

I don’t have any issue with a macerator as such, but as we’re connecting a shower and need to connect into the side of the macerator, this means the shower has to be raised? Not a deal breaker but would prefer a pretty much flat shower tray.

I was thinking of siting the macerator within an access hatch in the floor void under the toilet but can’t see a macerator unit that allows this (Saniflo’s instructions say specifically not to) other than a Sanicubic? No issue with this other than it’s a bit pricey! Can the waste drop straight up of the back of the toilet into this?

Ideas/suggestions most welcome.


Thanks again

Alan

 

[just pumps]

Thanks all - never thought about the maximum waste run.

There is an option for a new drainage run but this would mean lifting up the newly block paved driveway for most of its length.

I don’t have any issue with a macerator as such, but as we’re connecting a shower and need to connect into the side of the macerator, this means the shower has to be raised? Not a deal breaker but would prefer a pretty much flat shower tray.

I was thinking of siting the macerator within an access hatch in the floor void but can’t see a macerator unit that allows this (Saniflo’s instructions say specifically not to) other than a Sanicubic? No issue with this other than it’s a bit pricey! Can the waste drop straight up of the back of the toilet into this?

Ideas/suggestions most welcome.


Thanks again

Alan

Yes the waste does run straight from the pan to the cubic however believe me you wouldn`t use the cubic in your situation if you heard one before you brought it.
Congrats for reading the limits of the installation on Saniflo`s as so many people don`t and never site a macerator more than 50mm below the level of the pan. The current activation level on the Saniplus (my choice of model) is 130mm so shower tray can`t be flat to floor but people do build a raised floor giving the effect of a low level shower tray.

 

[Hot&Cold]

There is an option for a new drainage run but this would mean lifting up the newly block paved driveway for most of its length.

block paving V macerator.

Has a plumber/drain installer seen the job and quoted,there will be some building control involvement aswell. all good fun