[andybwells]

Couple things:

Am I crazy ....(Obviously)... or didn't this get answered by a bot earlier? Pretty good info, if I recall. Did they get brought to the train station?

Also, great and thorough explanation of the whole process, Mr. Fortyone.

You're not crazy Mr. Fortyone. That info was excellent and luckily I had a chance to read it. The bot or whatever was called "Drain Target Team" and I wish it was not deleted.

Andy W.

 

[andybwells]

Are you wondering why we wrap the pipes?

Fundamentally, because it’s required by Building Codes and it’s best practice.

Why is it required by Code?

Well, because it’s best practice. 😳

Why’s it best practice?

Well, anytime you have dissimilar materials with widely varying coefficients of expansion, those materials should be isolated to mitigate possible damage to one or the other material.

PVC, ABS, all plastics, expand and contract a great deal with temperature change. Drain pipes can have liquids anywhere from 40 degree well water to 140 degree dishwasher water going through them.

All that expansion and contraction happening in direct contact with a material that expands and contracts a few thousandths of an inch over 100 degrees, is not a good combination. Damage to the piping can occur.

I wrap mine with foam sill sealer. It comes in an 8” or 6” roll, and it gets taped around all the pipe that will be in contact with the concrete. So that’s from below the slab in the dirt, to a couple inches above the slab. It’ll get trimmed down after the slab is poured.

Seven,

That's good info. In addition, I spoke to a previous plumber. He pointed me in the direction of DWV Schedule 40. Some contractors will cut 4"-6" sections of the larger DWV schedule 40 as a drain sleeve, and use a link seal or other material as a packing to fill the space between the sleeve and drain pipe.

The Bot called Drain Targer Team that posted first on this thread (then was deleted by Contractor Talk) suggested drain sleeves also.

3M tuck and wrap strip, when used as a packing material between pipe and sleeve, provides a layer of fire protection if needed.

From what little research I have conducted this application is mostly used in foundation walls or footings.

I am leaning in the direction of a neoprene rubber or foam rolls with a removable strip at the top.

"Fastflex is a closed-cell polyethylene foam joint filler that is supplied with a convenient tear-off strip. When the tear–off strip is removed, it creates a void for the sealant in order to prevent surface cracking. Fastflex is available in continuous lengths in wall thicknesses of 3/8” and ½” and widths from 1” through 8”. " (WhiteCap.com).

I would like a clean and sealed edge around the pipe after the concrete is poured.

Andy w.