covering a drain pipe in a cement floor

sv9779 · 04-10-2009, 10:37 AM

I'm doing a room addition and the wall I am taking out has a 3 inch cast iron (might be steel) pipe in it. This area will be the middle of my new living room. I'll need to cut the pipe off and cement over it to level up the floor. Any ideas on what to cover the pipe with or thoughts on an easy way to do this?

Grampa Bud · 04-10-2009, 12:01 PM

If it's just cast iron a 16-22 oz framing hammer and a strong arm will bust it up fairly quickly. Make sure it's not a vent for your sewer or the sewer itself first. If you can legally take it out once the floor area is clear keep busting concrete around the hole about an 1" bigger than the hole itself. Go down about two inches and keep busting the cast iron down to that level if possible. Take a big plug of insulation and stuff it at least 6" down the hole, mix and 10# bag of sackrete towards the dry side and smooth it out with the top of concrete.

If it is steel you will need a sawzall with a metal cutting blade. (A Lenox 10 tooth x 8-10" bimetal blade should do it) Lay the blade down flat on the concrete and try to cut the STEEL pipe off perfectly flush with the top of concrete. Then jamb a tight plug of insulation about 6" down the pipe and mix your concrete and smooth off level withtop of concrete.

majakdragon · 04-10-2009, 01:59 PM

Make sure you know what that pipe is for before cutting it off. 3" cast or steel sounds like a vent line. where does it go after coming out of the floor? If the house is 2 story, it may be the main drain for upstairs fixtures. If you do fill it in, make some sort of a stopper a few inches below the top of the pipe and then fill it in. It may connect to a tee under the flor and just "throwing" some cement into the pipe could clog a connecting pipe.

al's sewer · 04-10-2009, 03:10 PM

after you get the pipe below floor level I like to use an expandable plug and hydralic cement to finish to floor level.

wrangler · 04-10-2009, 09:42 PM

At the MINIMUM get a plumber in there to tell you what the pipe is for! You could end up with a nightmare if you cut the pipe with no knowledge of its purpose. As stated before, it might be part of the venting (which will affect your other plumbing) or even worse, the actual drain. It would NOT have been installed for no reason in the first place. In the end, it might be easier to make a decorative post around it than to just cut it off and fill it in.

sv9779 · 04-10-2009, 10:35 PM

Thanks guys' It is a single story house and it is a vent. It is the drain and vent for the kitchen sink. There is a washer drain about 5 feet away but it has it's own vent. Both of which will be moved to new plumbing drain lines. The only other drains for the two bathrooms are 30 feet away at the other end of the house. So I should be able to remove it without effecting any other drains.
Thanks for the help