Plumbing best practise

rampantbunny

Hi. Starting first fix plumbing over the xmas period. Just wondering if there are any best practices that should be followed in relation to running waste pipes from showers, baths, sinks.

Plumber has suggested that all wastes can be joined into one before exiting house, as it's highly unlikely that bath and shower will be used at same time, or sink.
Makes sense, but I don't want to be using shower and listening to sink burbling if that's even a concern (I've been in some houses before and heard this).

aujopimur

You need a better plumber.

rampantbunny

aujopimur wrote: »

You need a better plumber.

OK. Reading between the line, separate runs for all wastes?

aujopimur

rampantbunny wrote: »

OK. Reading between the line, separate runs for all wastes?

Yes.

corkgsxr

Depends.

Run them into a 4 inch and then out.

Or sink and bath into a 2" or sink and shower.

But not more than 2


But more than likely he's running them all in 11/2 which is too small.

rampantbunny

corkgsxr wrote: »

Depends.

Run them into a 4 inch and then out.

Or sink and bath into a 2" or sink and shower.

But not more than 2


But more than likely he's running them all in 11/2 which is too small.

If they can be combined into one pipe, I take it that cross-talk between the pipes is not an issue. By cross-talk I mean noise/gurgling (or even odors) etc. between pipes.
And the issue is volume?

Dtp1979

rampantbunny wrote: »

If they can be combined into one pipe, I take it that cross-talk between the pipes is not an issue. By cross-talk I mean noise/gurgling (or even odors) etc. between pipes.
And the issue is volume?

2" would be the minimum. I'd also fit air inlet valves on the line

corkgsxr

rampantbunny wrote: »

If they can be combined into one pipe, I take it that cross-talk between the pipes is not an issue. By cross-talk I mean noise/gurgling (or even odors) etc. between pipes.
And the issue is volume?

Yep.

What that is is the pipe running full flow and sucking the traps out of the other outlets.

If the main run is bigger it won't happen.

Calahonda52

corkgsxr wrote: »

Yep.

What that is is the pipe running full flow and sucking the traps out of the other outlets.

If the main run is bigger it won't happen.

vs

corkgsxr wrote: »

Depends.

Run them into a 4 inch and then out.

Or sink and bath into a 2" or sink and shower.

But not more than 2


But more than likely he's running them all in 11/2 which is too small.

Make up your mind time here I think, smaller or bigger?:D


OP
Joining them all up inside, without adequate provision for avoiding the traps being sucked out is just lazy bad plumbing
I suspect u meant bigger:D

rampantbunny

Calahonda52 wrote: »

vs



Make up your mind time here I think, smaller or bigger?:D


OP
Joining them all up inside, without adequate provision for avoiding the traps being sucked out is just lazy bad plumbing
I suspect u meant bigger:D

Sorry Calahonda...not sure who you're addressing?
I've taken it from the above posts that plumber should either:

1. run separate wastes for all to outside
2. run separate wastes for all into a 4" pipe, then to outside
3. run sink/bath together in one, or sink/shower in one waste pipe max

FWIW; in one bathroom I've already a 4" duct for taking waste water away, but only because I didn't want to see multiple white waste pipes exiting the house. Almost accidental. Will see if I can get more 4 inch pipes into others.

Are collars/joiners readily available for running 1.5" wastes into the side of 4" pipes?
Local hardware is a small outfit and don't have a very wide range of fittings.

Dtp1979

Op here's the the best practice on order
1. Run wastes out seperatley
2. Run in a 4" pipe and join into it. Use air inlet valves too
3. Same as above using 2" pipe. Not as good as 4"
4. Join into 1 1/2. This method is bad practice.

corkgsxr

Calahonda52 wrote: »

vs



Make up your mind time here I think, smaller or bigger?:D


OP
Joining them all up inside, without adequate provision for avoiding the traps being sucked out is just lazy bad plumbing
I suspect u meant bigger:D

I gave 2 options.

One where you run a 11/4 and 11/2 into a 2 inch pipe. In which case the main run is bigger

Or where you run a 11/4 and 11/2 into a 4 inch pipe. In which case the main run is bigger.

I'd Deem them acceptable.

corkgsxr

rampantbunny wrote: »

Sorry Calahonda...not sure who you're addressing?
I've taken it from the above posts that plumber should either:

1. run separate wastes for all to outside
2. run separate wastes for all into a 4" pipe, then to outside
3. run sink/bath together in one, or sink/shower in one waste pipe max

FWIW; in one bathroom I've already a 4" duct for taking waste water away, but only because I didn't want to see multiple white waste pipes exiting the house. Almost accidental. Will see if I can get more 4 inch pipes into others.

Are collars/joiners readily available for running 1.5" wastes into the side of 4" pipes?
Local hardware is a small outfit and don't have a very wide range of fittings.

Yes it's called a strap boss. Just make sure it's the glued type. One sort have a rubber seal which will shrink over time and start leaking.

Irish Steve

As it's not been mentioned so far, the most important thing for me would be to have as few as possible 90 degree bends under floors in any pipe size that's under 4 inch, as they can be a nightmare to clean if they become blocked. Keep the pipe run lengths of smaller bore pipes as short as possible, especially on kitchen sinks or wash hand basins and bathroom sinks.

Avoid joining any pipes where one of the contributors to the lines is a pumped outlet like a washing machine or dish washer, if the pipe blocks downstream from the join, there's a risk of the pump causing flow back up the line to the other source, which can cause problems if it's not a large capacity.

If possible, avoid the standpipe type outlet for washing machines or dishwashers, if possible, go for the type of connection that has a hose clip holding the outlet pipe on to the discharge pipe, to avoid the risk of an overflow if the pipe becomes blocked, though an air vent may be needed for a "closed" pipe.

Joining smaller bore pipes to a 4" can be a problem on upper floors, depending on the joist directions and the pipe directions, as the smaller bore pipe may not end up even close to floor level, which can cause huge problems with the eventual height of shower trays or baths. The only solution to that issue is to join to the 4" where it is running between the joists, or where it's running vertically through the joists or outside of the building, if the 4" is running horizontally above the joist line from a WC, it will be unusable for a shower or bath on that floor. (Don't ask how I found that one out!!)