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jman2012
Jan 13, 2013, 06:29 PM
I am moving a bathroom on the concrete slab level of our split level house. I busted through the concrete and I dug the trench for the new drain pipe. The soil was a little on the soft side so I had to tamp it down quite a bit to get it nice and solid. Through the tamping and the initial trenching process, I need to build and grade the surface to lay the pipe in. Is QUIKRETE® All-Purpose Sand acceptable to use for this or do I need to use the fine play sand? The QUIKRETE® All-Purpose Sand is a coarse sand. I planned to put a bed of the sand (whichever one I can use) under and over the pipe. Also, what depth of sand is needed over the pipe before I change materials? When I change materials, should I use dirt or some sort of gravel. I live in northern Ohio, so the only thing I can get that is not frozen is QUIKRETE® All-Purpose Gravel (No. 1151) for the gravel. Is this acceptable to use?

I was originally going to tap into the existing cast iron pipe under the slab, however, I was a little concerned about the joint between the PVC and the cast iron. I have decided to replace the cast iron with PVC. The cast iron runs through a masonry wall into the basement. When I run the PVC through the masonary wall, does it need a sleeve? If so, what materials are acceptable for a sleeve? I will then connect the PVC the exposed cast iron so I would be able to easily maintain it if necessary.

QUIKRETE® All-Purpose Sand (No. 1152) is a washed, properly graded coarse sand with multi-purpose uses. Meets ASTM C 33 specifications. - QUIKRETE® - Sand - All-Purpose (http://www.quikrete.com/productlines/SandAllPurpose.asp)

QUIKRETE® All-Purpose Gravel (No. 1151) is a multi-use product for a variety of decorative and landscaping applications. Also for making concrete. - QUIKRETE® - Gravel - All-Purpose (http://www.quikrete.com/productlines/GravelAllPurpose.asp)

massplumber2008
Jan 14, 2013, 08:37 AM
All purpose sand is fine, and pea stone gravel is fine for the beddding and covering the top of the pipe. Cover to 1-2" above the pipe and then transition over to gravel or dirt.. whichever floats your boat as both are acceptable as long as there are no large stones/rocks.

Sleeve the PVC through the wall. A good sleeve is a larger PVC pipe, or a piece of cast iron pipe... anything like that will work. Fill the annular space (space between sleeve and pipe) with silicone sealant or hydraulic cement.

In terms of connection between PVC and cast iron, I may be able to save you some time and money and reassure you that we make transitions like this underground all the time with no issues whatsoever. The important factor here is to purchase the proper transition clamp. Here, the all rubber fernco clamps with 2 SS bands is actually approved in many states and work fine. Another, what I consider better alternative, is the shielded band clamp... see image. Just purchase the PVC x cast iron clamp and you should be fine!

Good luck!

Mark

jman2012
Jan 14, 2013, 07:54 PM
Thanks for the answers and reassurance with the connection between the PVC and cast iron. I was getting a little nervous with that approach as I was getting closer to implement. I will go with using the shielded band clamp, which will save a bunch of work and time.

Relative to the connection between the PVC and cast iron I had a few questions. I used the chain type soil pipe cutter to cut the cast iron. I used a miter saw to cut the PVC. I filed the cut on the cast iron to try to get it as true of a surface as possible for the joint. When I place the PVC up to the cast iron to see how true of a joint I have, there are some gaps no greater than 1/16th of an inch. Is this amount of spacing acceptable or does it need to be perfectly true? If so, any pointers or tools I could use on the cast iron that would enable me to get that perfectly true joint? Do I need to paint the filed surface to prevent any rusting? After I join the pipes with the shielded band clamp, do I need to do anything else with that joint other than covering it like I cover the rest of the pipe?

I will have a sink drain that will come up from the concrete floor. Does this drain pipe need any type of sleeve around it? For that matter, does toilet or shower drains need any sleeving or is it OK to pour the concrete around the PVC?

Thanks again for all your help on this project.

massplumber2008
Jan 14, 2013, 08:08 PM
Glad to help...

There are extra heavy cast iron pipes/fittings (marked XH on fittings) and service weight cast iron pipe/fittings (marked SV on fittings).. can make a difference in the clamp chosen here! See if you can find these marks on the hub of the fittings and let me know what you find. 1/16"th inch doesn't sound like much of an issue either way and no need to paint the filed end.

Cover the pipe/joint as the PVC pipe...no difference.

Schools differ on coming through the floor with pipe...can have no or some insulation. I use a pipe insulation or simple cardboard wrapped around the pipe (a few wraps)...can't hurt, but really not necessary as I see tons of pipes without insulation and they are fine decades later, OK?

With that being said, a toilet drain needs a sleeve around the drain pipe to acommodate the flange. The shower drain needs a minimum 6" hole around the drain in case you need to make any adjustments to the drain. I use a used coffee can for this.

Back to you...

Mark

jman2012
Jan 15, 2013, 06:57 PM
I was going to use the Fernco 4 in. No-Hub Cast Iron x 4 in. Sch 40 PVC, Steel and Extra Heavy Cast Iron Neoprene Rubber Shielded Coupling that I got at Home Depot. Fernco 4 in. No-Hub Cast Iron x 4 in. Sch 40 PVC, Steel and Extra Heavy Cast Iron Neoprene Rubber Shielded Coupling P3000-44 at The Home Depot (http://www.homedepot.com/buy/fernco-4-in-no-hub-cast-iron-x-4-in-sch-40-pvc-steel-and-extra-heavy-cast-iron-neoprene-rubber-shielded-coupling-p3000-44.html). Would I be better off using one from Charlotte Pipe? http://www.charlottepipe.com/Products/Assets/02A-Cast_Iron_List_Price/SDC-711.pdf Does it matter which one I use? The Charlotte pipe one looks to be a little more substantial than the Fernco.

Thanks for the advice on using either pipe insulation or cardboard. I’ll use the pipe insulation.

For the toilet drain, I have a 4” pipe. I was going to cut if flush with the floor and then use the Oatey 4 "Dia. PVC Flange that fits inside the 4” pipe.

Shop Oatey 4 "Dia. PVC Flange at Lowes.com (http://www.lowes.com/pd_253219-138-434953_0__?productId=3137591&Ntt=oatey+flange&pl=1&currentURL=%3FNtt%3Doatey%2Bflange&facetInfo=) Is this an OK approach?

For the shower, I was going to use a Mueller Streamline 2” PVC DWV Hub x Hub P-Trap. 3 in. PVC DWV Hub x Hub P-Trap-05230H at The Home Depot (http://www.homedepot.com/Plumbing-Pipes-Fittings-Valves-PVC-Pipe-Fittings-Fittings-Traps/h_d1/N-25ecodZ5yc1vZ25ecodZ25ecodZ25ecodZ25ecodZbux7/R-100163652/h_d2/ProductDisplay?catalogId=10053&langId=-1&keyword=Mueller&storeId=10051) (I could not find a link to the 2”). Is this a good one to use? The P-Trap is a two piece unit. Do I need to cement the two pieces together? The two pieces are really snug and I was not sure if they are designed to be not be cemented together. I planned to cement them together.

Regarding the 6” hole around the drain for the shower. Do I need to make the entire hole encased in cement or should the bottom be an aggregate? Should the entire P-Trap be located in the 6” hole so it would allow for any adjustments be made to the P-Trap. Or should the adjustments be made from the P-Trap using fittings? I am having a hard time visualizing how this or will work

massplumber2008
Jan 16, 2013, 07:25 PM
Use the Charlotte pipe one. In my opinion, the 4 band always beats the 2band clamp!

Oatey flange inside the pipe is a perfect approach!

Cement the 2" Ptrap together, for sure. This means that the shower rough in needs to be spot on, so check your measurements twice, OK?

Checking the measures at the shower drain (placement back to front and left to right)..need to be dead on. This means that you need to have the PTRAP placed so the riser out of the trap is correctly positioned within the 6" hole in relation to the shower base. The 6" hole is to accommodate the STRAINER from the shower, not the pipe/trap!