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Floor drain

Youstina

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Joined
Jul 15, 2022
Messages
15
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I'm in the process of building my home. Is it a good idea to have a floor drain in the bathroom or not, because it is not common here in US to have it and I would like to know if it has more cons or pros.
 
@ ~ @

Youstina, ...a floor drain is atypical in a residential
application in the U.S.......If you decide to install one,
the P-Trap will need to be monitored to ensure
that the trap seal is kept intact [ e.g. - a maintenance
issue ].


@ ~ @
 
I have inspected a fair amount of homes having floor drains in a bathroom. A trap primer was always installed. Trap primer serve the purpose to maintain a water seal in the trap to avoid sewage smell within the room or house however in my area we typically have hard water and if this water is not treated by means of a water softener or similar then the trap primers tend to become clogged and not perform its function.
 
I have inspected a fair amount of homes having floor drains in a bathroom. A trap primer was always installed.
Did the bathroom floor slope to the drain? I have never seen a residential bathroom with a floor drain. I have seen laundry pans with drains on second floors.
 
There are certain layouts/designs that make a floor drain advantageous. The pro is it can keep a house from flooding, con is it requires a primer and maintenance, as described by others.
 
You may be able to use one of these instead of a trap primer....

1002.4.1.4 Barrier-type trap seal protection device.
A barrier-type trap seal protection device shall protect
the floor drain trap seal from evaporation. Barrier-type
floor drain trap seal protection devices shall conform
to ASSE 1072. The devices shall be installed in accordance
with the manufacturer’s instructions.
 
I have inspected a fair amount of homes having floor drains in a bathroom. A trap primer was always installed. Trap primer serve the purpose to maintain a water seal in the trap to avoid sewage smell within the room or house however in my area we typically have hard water and if this water is not treated by means of a water softener or similar then the trap primers tend to become clogged and not perform its function.
Legitimate question..if trap primers don’t work well in your area, do local building officials bar floor drains from being installed in bathrooms?
 
Mineral oil. Definitely not vegetable oil, as e Hilton kindly reminded me.
My CBO is against any type of oil in a trap due to flammability concerns. He said that if someone installs a floor drain in a bathroom, since it is used everyday, the occupant can pour water in the drain every so often..or put a floor drain cover.
 
In my own house, I have to have a floor drain (slab at grade). I also need a drain for a thermosiphon pressure valve. The plumbers concocted a system where both are upstream of a trap that's charged by the (second storey) washing machine.
 
My CBO is against any type of oil in a trap due to flammability concerns. He said that if someone installs a floor drain in a bathroom, since it is used everyday, the occupant can pour water in the drain every so often..or put a floor drain cover.
THAT IS if the trap primer doesn't work.
 
the occupant can pour water in the drain every so often..or put a floor drain cover.
Yeah, when the trap goes dry and the house smells like sh… and nobody remembers what to do.

Good idea … put a cover on the drain … keep the water from draining out.

WV … not picking on you, but those are both stupid ideas, clearly proposed by someone with no common sense. Someone with a nimby attitude.
 
Yeah, when the trap goes dry and the house smells like sh… and nobody remembers what to do.

Good idea … put a cover on the drain … keep the water from draining out.

WV … not picking on you, but those are both stupid ideas, clearly proposed by someone with no common sense. Someone with a nimby attitude.
Simply quoting the CBO, wasn't my idea. You said it, not me lol
 
I understand that in Europe, some people construct the shower floor to be the ENTIRE BATHROOM so that any mishap would not damage the area below the bathroom.

Takes care of keeping the trap's water seal

What do you think?
 
We have seventeen traps that could dry out. I have to remember to run water in six of them because they seldom get wet. There’s nothing unusual about our home. If we had a floor drain there would just be seven to remember. The point is that a trap primer is not required. There is a built in reminder. If you have a wife it comes with enunciation.
 
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