Home Page link

shared plumbing trench

Home| Search | About
Login Password
Register Now! Lost Password?

Building Construction - Building Construction Industry Discussions. 

Bookmark this page:  YahooMyWeb Yahoo!  Google Google  Windows Live Favorites Windows Live  del.icio.us del.icio.us  digg digg  Add to Netscape Netscape
Subject Author Date
shared plumbing trench EricY 04-19-2007
If you were  Registered and logged in, you could reply and use other advanced thread options
Posted by EricY on April 19, 2007, 10:10 am
I have a detached garage that serves as my woodworking shop. My latest
project involves installing thermal solar collectors on the shop roof and
piping the hot water back to the house provide heat for the domestic water
heater.

Part of this project will involve a 40' trench from the shop to the house
for the solar heating pipes - hot supply and cold return. Currently the
shop does not have any plumbing. I was thinking that while I've got the
trench open I could run a water line from the house to the shop and and a
sewer line for a utility sink.

Altogether the trench would have:

2 insulated pipes for the solar heating system
1 cold water line to the shop from the house
1 sewer line from the shop to the house

I should add that the floor of the shop is slightly above grade and the
pipes will be run to the house basement, the floor of which is about 5 or 6
feet below grade. I only want to install one utility sink in the shop; no
toilet.

My questions:

1) Is this shared trench a massive code violation in the US? (located in
VA)
2) What is the smallest sewer/drain line that can be installed in such a
scenario? I have an ideal location to tie into the house's sewer via a 3"
tee
3) IIRC the drop for a sewer line should be 1/4" per foot - is this about
right?

Thanks for any help you can provide!

Eric



Posted by marson on April 19, 2007, 10:48 pm
wrote:
> I have a detached garage that serves as my woodworking shop. My latest
> project involves installing thermal solar collectors on the shop roof and
> piping the hot water back to the house provide heat for the domestic water
> heater.
>
> Part of this project will involve a 40' trench from the shop to the house
> for the solar heating pipes - hot supply and cold return. Currently the
> shop does not have any plumbing. I was thinking that while I've got the
> trench open I could run a water line from the house to the shop and and a
> sewer line for a utility sink.
>
> Altogether the trench would have:
>
> 2 insulated pipes for the solar heating system
> 1 cold water line to the shop from the house
> 1 sewer line from the shop to the house
>
> I should add that the floor of the shop is slightly above grade and the
> pipes will be run to the house basement, the floor of which is about 5 or 6
> feet below grade. I only want to install one utility sink in the shop; no
> toilet.
>
> My questions:
>
> 1) Is this shared trench a massive code violation in the US? (located in
> VA)
> 2) What is the smallest sewer/drain line that can be installed in such a
> scenario? I have an ideal location to tie into the house's sewer via a 3"
> tee
> 3) IIRC the drop for a sewer line should be 1/4" per foot - is this about
> right?
>
> Thanks for any help you can provide!
>
> Eric

Eric, since noone else is answering, I'll take a stab at it. I'll
warn you, I'm no expert, but have picked up some things as a
contractor working with excavation subs.

A shared trench is not a code violation. water and sewer is regularly
run in the same trench. I believe they have to be three feet apart.
I doubt if your solar hot water lines would be governed by code.

Don't know the answer to number 2. Seems like would be governed by
plumbing code as it applies to the plumbing in your shop. (My current
project has a forced main, and that has a 1 1/4" sewer line!)

I believe the slope in a buried sewer line can be as little as 1%.
Don't quote me on that either. I know it is less than 1/4 per foot
though. Course that is the slope from the house to a city sewer.
Yours is a different situation.

Do you have a building department you can call? That would be the
best place to get some answers.


Posted by Dave on April 19, 2007, 11:46 pm
>I have a detached garage that serves as my woodworking shop. My latest
>project involves installing thermal solar collectors on the shop roof and
>piping the hot water back to the house provide heat for the domestic water
>heater.
>
> Part of this project will involve a 40' trench from the shop to the house
> for the solar heating pipes - hot supply and cold return. Currently the
> shop does not have any plumbing. I was thinking that while I've got the
> trench open I could run a water line from the house to the shop and and a
> sewer line for a utility sink.
>
> Altogether the trench would have:
>
> 2 insulated pipes for the solar heating system
> 1 cold water line to the shop from the house
> 1 sewer line from the shop to the house
>
> I should add that the floor of the shop is slightly above grade and the
> pipes will be run to the house basement, the floor of which is about 5 or
> 6 feet below grade. I only want to install one utility sink in the shop;
> no toilet.
>
> My questions:
>
> 1) Is this shared trench a massive code violation in the US? (located in
> VA)

There is no U.S.-wide plumbing code that I'm aware of. Particular to VA,
not sure.

> 2) What is the smallest sewer/drain line that can be installed in such a
> scenario? I have an ideal location to tie into the house's sewer via a 3"
> tee

Standard drain pipe is 4". Don't use DWV underground.

> 3) IIRC the drop for a sewer line should be 1/4" per foot - is this about
> right?

That will drain the liquids in the line without leaving too much sediment
behind.
--
Dave

Apathy and denial are close cousins



Posted by DT on April 20, 2007, 9:45 am

>1) Is this shared trench a massive code violation in the US?

Perfectly OK. Be sure and follow your city's code for burial depth if it is a
freezing area.

>2) What is the smallest sewer/drain line that can be installed in such a
>scenario? I have an ideal location to tie into the house's sewer via a 3"
>tee

It's really just a lateral for a single fixture. I wouldn't use anything less
than 2", although since it is a separate building, I bet code would require
that it be a main, 3". Be sure and add a vent in the garage for the sink,
especially with such a long run. Under the sink you will have a trap, then tee
in on the house side of it and run 2" through the roof.


>3) IIRC the drop for a sewer line should be 1/4" per foot...

That's correct.

One other thing: be sure and slope all lines back towards the house so you can
drain them if necessary.

--
Dennis


Posted by EricY on April 20, 2007, 12:56 pm

>
>>1) Is this shared trench a massive code violation in the US?
>
> Perfectly OK. Be sure and follow your city's code for burial depth if it
> is a
> freezing area.
>
>>2) What is the smallest sewer/drain line that can be installed in such a
>>scenario? I have an ideal location to tie into the house's sewer via a 3"
>>tee
>
> It's really just a lateral for a single fixture. I wouldn't use anything
> less
> than 2", although since it is a separate building, I bet code would
> require
> that it be a main, 3". Be sure and add a vent in the garage for the sink,
> especially with such a long run. Under the sink you will have a trap, then
> tee
> in on the house side of it and run 2" through the roof.
>
>
>>3) IIRC the drop for a sewer line should be 1/4" per foot...
>
> That's correct.
>
> One other thing: be sure and slope all lines back towards the house so you
> can
> drain them if necessary.
>
> --
> Dennis
>

Thanks to everyone for your responses and assistance. It sounds like my
approach is feasible enough to talk to the local building officials.

Thanks again,

Eric



Similar ThreadsPosted
Water trailer for dust control, fire control, cement saw, asphalt roller, trench jetting, etc June 27, 2007, 8:22 am
New plumbing site April 11, 2007, 11:36 am
Plumbing and venting costs July 31, 2006, 4:52 pm
No more sweating--plumbing question August 11, 2006, 2:33 am
Simple Plumbing question September 28, 2006, 11:04 am
Plumbing rough-in before roofer? April 13, 2007, 12:41 pm
Propane plumbing questions March 18, 2008, 4:22 am
Plumbing question: Y connector on vertical drain December 20, 2006, 8:15 am
kitchen remodle dishwasher plumbing advice March 9, 2007, 4:54 pm
Plumbing Question: Shower Escutcheon Removal September 25, 2007, 1:09 pm

Contact Us | Privacy Policy

XML SitemapXML Sitemap