Plumbing question?

[Ned Flanders]

I have to install a utility sink in my unheated garage (I don't think I have ever seen it below freezing) for my wife's new business... the floor of the garage is a foot lower than the first floor of the house (built on slab).

My unfinished utility room is on the opposite side of the wall. The utility room has the stack on the far side, and incoming cold water and hot water tank.

I plan on running PEX from the hot and cold lines (copper) to two frost free taps over the tub (probably not necessary but may as well so they can be weatherized if needed).

For the drain i believe my best option is to use a under sink sump pump with a 8 foot header then less than a two foot run to an existing 2" drain pipe with a vent behind it that runs right into the stack a few feet further.

The pump I bought also needs venting and that is right there as well (or I can use a cheater?).

I am leaning towards taking the drain and vent into the wall to the warm side right after the check valve so that any leaks at the check valve would be into the garage. With the water that will always be in the pipe there should not be any chance of freezing in the check valve.

The only place it might freeze would be in the pump tank, but I could always wrap it with heat tape if needed?

Your thoughts would be appreciated.

[trader4]

The problem with that is you wind up with two seperate taps above the sink instead of a hot and cold that feeds into a central spigot for the sink, no? Unless there is a frostproof two into one, which there may be. I don't know how the sink is going to be used, but the fact that it's for a business suggests that it's going to get some real use and having it work like a real sink where you can mix the hot and cold may be essential.

Not sure what that means. If the check valve is in the garage, then it can freeze. You might want to consider running the drain into the utility space in the basement and putting the pump there. That takes freezing out of the equation for the pump system. The only thing that could freeze would be the sink trap. It does introduce the problem of a pump failure resulting in water on the basement floor. How much of an issue that is depends on where the water would go, if it's just cement floor, etc. You could place one of the $10 water alarms you can buy at HD next to the pump. Or perhaps have an overflow pan, like for a WH, that then flows to a sump pump pit, french drain, etc.

[hrhofmann]

He says everything is on a slab.

[Ned Flanders]

My plan was to use hose connections (like you would for a washing machine) to supply the taps on the sink. She is going to need the ability to set the temp and control the flow from a single valve like you would find in most commercial settings. These could be disconnected to weatherize if the temperature was going to be concern.

I think this is a chance I might have to take because i would have to raise the sink almost 15" to allow the sink to drain into the utility room and into a sump. My house does not have a basement or even a crawl space and do not want to jackhammer into my slab as this area has lots of going on inside the slab such as heat ducts and water supply lines.

Like i said it is unlikely it will get cold enough to freeze but I can add measures to make sure it doesn't happen, such as heat tape etc. With it inside the garage the chance of the water causing too much damage is minimal and the same can not be said for having the sump, check valve, and a 7' head inside the house.

Thank you, some good things to consider.

[DerbyDad03]

Somebody has to ask...

A business? In your garage?

Any zoning/insurance issues that you need to address?

DIY plumbing for a business in a residential neighborhood raises some flags, that's all.

[Ned Flanders]

The type of business is legal for a home here and I don't anticipate any insurance issues but I am dealing with that the week so I will find out then.

My wife is a certified dog groomer so she needs place to wash the dogs.

As a jack of all trades crossed with a bit of a perfectionist, I just like to over plan my projects.

[dpb]

On 3/6/2013 1:04 PM, Ned Flanders wrote: ...

...

Our initial utility room in the TN house was on slab garage floor below house floor level, too....

I built false floor and raised it up to same height -- in that house the roofline was flat over both house/garage so ceiling height was the same; the builder just did it on the cheap initially...in that case it was full width of double garage so cut off a third or so as storage then also put a removable hatch in the floor and was able to put stuff that was very rarely used down there as well.

Perhaps you could do the same/similar and avoid the sump as well as need for check valves and all that folderol...

If she's going to work out there, might as well insulate and add a branch off the heat as well...

Just a thought based on past experience.

[DerbyDad03]

I hope you're stepping up and getting her one of these:

She deserves it!

[The Daring Dufas]

Um, that's so his wife can wash dogs, not herself, right? O_o

TDD

[hrhofmann]

great ideas!!!

[clare]

No problem, in most cases, if there is no commercial traffic. I've operated my business out of the house for 20 some years with the full blessing of the city - not even a business licence required.

[Ned Flanders]

Great ideas, but a sub floor is out of the question as we have decided to make all of her equipment (other than the sink) movable so that in a pinch we can still use the space as a garage. The sink is going in where my tool bench once was, my SUV still uses the far side and when needed her car will have to be able to be stuffed into the garage.

I do however plan on changing out the garage doors to insulated doors and I already have heat running above into the bonus room, so dropping heat into the garage will be very easy.

[chaniarts]

check on the building code for that. a duct into the garage that leads back to the main house might be a bad idea (vapors, fire, etc).

[Ned Flanders]

Yes thanks, I actually thought about that earlier today. I am sure it will not be allowed and in addition to the possibility of vapors it also would not be good for the efficiency of the furnace as there is no cold air return.

I will just go with my original plan of electrical heat.