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mooney10
Apr 2, 2008, 05:25 PM
I'm installing a shower in the basement in an older house, it has a p trap about 3 feet strait down under the shower! Should I put a p trap directly under the shower? Or would this cause burping with 2 p traps in the line?

massplumber2008
Apr 2, 2008, 05:39 PM
Hi Mooney:

Hey... 3 feet is pushing it... BUT... you cannot connect any drain using 2 ptraps... no exceptions to this! So stick with what you have at this point and connect riser to shower drain. Is drain off center of shower... or directly under?

What kind of shower? Describe as much as you can. Is there a pre-molded shower floor... or a custom pan? Let me know... few tricks go with each type... Mark

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mooney10
Apr 2, 2008, 06:07 PM
Thanks for the Quick Answer, the Drain is off center about 12", The Pan is A Kohler fiberglass 36X60 so had to move the drain 12" it was originally set up for a 36x36 . It is a cast iron riser.

massplumber2008
Apr 2, 2008, 06:19 PM
Mooney:

Unless you want to dig down three feet, you want to dig down a foot or so... cut the cast iron riser (will not be easy...talk to me about this if going to do it yourself).. and OFFSET the drain using PVC pipe and (2) 45 degree fittings into the new pvc drain assembly of the fiberglass pan. Use a 2" PVC x 2" cast iron shielded coupling (code approved) to make the transition between 2" cast iron and 2" PVC pipe (available at all plumbing supply houses).

Also want to set that fiberglass shower pan into a bed of perlited gypsum structolite mortar or a modified thinset mortar bed to reduce sqeeeks/motion at pan. Also, talk to me if planning to do yourself.

Let me know what you think... Mark

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mooney10
Apr 2, 2008, 06:38 PM
I already cut the pipe and have the shielded coupling, but I bought 2 90s should I go with the 45s? Also I plan to set the pan myself.

massplumber2008
Apr 2, 2008, 06:43 PM
Yes... you need to purchase (2) 45s. Code frowns on 90s... ;)

If planning pan... check out this site:

How to Build a Shower Pan (http://www.hoagy.org/house/HowToBuildShowerPan.html)

Get back to us if need more... Mark

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mooney10
Apr 2, 2008, 06:47 PM
Thank you for all of your help! You have been Great source of Information! Thanks again.

I will follow all of your advice

mooney10
Apr 2, 2008, 06:59 PM
Mark
I'm going to set the fiberglass pan myself, so I should set it in a base of thinset morter,how thick shoul it be?

massplumber2008
Apr 2, 2008, 07:20 PM
Hey Mooney:

Look at shower base... will see outer perimeter and base itself. At base, want between 2-4 inches of MODIFIED thinset mortar (sold in buckets at home supply) or structolite, and then push down tight to floor so that base is level from front to back and from side to side (dry fit this... i.e. practice this.. then when understand floor, base, and corners of walls... set in mortar for best result). Look at base... add 1 inch more than you think you need... then let dry overnight before stepping into/on shower floor... that should do it.

Let us know what you think... anytime... Mark