Toilets, sinks and more

HondurasInternArchitect · Jul 21, 2011

So I am currently working as an intern architect for an environmental construction firm in Honduras. I was assigned to design an office addition to include a male and female bathroom, a conference room and a control room. This may sound simple, but being from the states I am not too familiar with the metric system or how they normally do construction here in Honduras.

I am wondering about proper venting for toilets, showers and sinks. I was told by the father of my boss here (he's from Canada) that for sinks you should include a T on the drain pipe and have a stand pipe (capped for pressure equalization) so you don't have the water hammer effect.

I am used to the states where the vent pipe from toilets is collected at each floor then put straight through the roof and out to the elements. Does it make sense for me to put a T on the drain pipe and have the stand pipe go all the way up, collect the other toilet vent pipes and out the building at the side at roof level?

If it is possible I would like to not penetrate the roof because the rainy season here is quite rediculous and I wouldn't want the bathroom to turn into a lake.

Any comments would be a great help, thanks.
Brook

LiQuId · Jul 24, 2011

You can combine individual vents to form a header or branch is is allowed but must be sized properly.

The T for water hammer your buddy was referring to Would be on the pressureized domestic water and not the drainage ( drainage PSI is typically not more than 3-5 psi at max ) this is called an Air chambe and Was the way to do it untill a few years ago when code decided that mechanical arrestiors worked better and as such you re not allowed to fabricate them anymore.

it is a fairly simple job by the sounds, you are taking a good step in doing homework.

LiQuId · Jul 24, 2011

depending on local codes there is nothing that says a vent cannot terminate on an outside wall, there are clearances that you must watch for

HondurasInternArchitect · Jul 26, 2011

Thanks for the help. In case you were curious there aren't many codes in Honduras per se. I studied how to design buildings and systems in the U.S. so I am stuck trying to do some things the right way and most are used to a quicker cheaper alternative.

That being said, if I wanted to do the water hammer problem solving technique do I just extend the hot and cold leads past where the faucet's are about 2' then cap it? I was told that if I did that it would equalize the pressure then flow back to where you were brushing your teeth or whatever.

HondurasInternArchitect · Jul 26, 2011

On a separate note, in regard to showers, where should the u trap be placed if at all?
It is common here to do the U trap for showers further along the line or possibly outside where it can be dug up and drained.
It doesn't make sense to me to vent a shower drain before you have the U trap.

LiQuId · Jul 28, 2011

P trap, installed under the shower pan. usually above the celing below.

Fabricated arrestors ( when we were allowed to make em ) were usually installed in the wall. instaed of terminating the domestic water run with a 90 to stub out of the wall a T was used and the top of the T would be a 1 foot minimum peice of pipe with a cap on it. it works because the air that gets trapped in the chamber is compressablle and will compress a little when the hammer occurs, if there was no chamber then the water hammer force must go somewhere as water is non compressablle and so the force would resonate through the pipes and the force would be re-directed by pipe deflection