Cutting My Basement Floor - Plumbing - DIY Home Improvement | DIYChatroom

Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Plumbing


Thread Tools Display Modes
Old 04-19-2010, 01:11 PM   #1
Join Date: Apr 2010
Posts: 1
Rewards Points: 10

cutting my basement floor

hi, new here and need some advice.
i need to replace all my cast iron sewer lines under my basement floor.
my question is, will cutting my floor basically in two or pieces wise?
is this going to cause me problems years later, with shifting and getting
uneven ?
could it be done with leaving sections together. like small bridges, if you know
what i mean.

thanks, jeffm


jeffm2 is offline   Reply With Quote
Old 04-19-2010, 01:29 PM   #2
Join Date: Jan 2008
Location: Alabama
Posts: 608
Rewards Points: 500

As an educated guess, if there were pressures that were going to cause shifting and unevenness, I doubt "small bridges" would make a difference.

Having never done anything like this myself, if I was doing it as a DIY project, I would try to first cut a skinny trench just to open the concrete. Then, where I wanted the final openings, cut only the 1st 1" or so, and use a sledge hammer to bust open the rest of the concreate. That way, you'll have some subterainian rough edges for the new concrete to bite to tie it all back together, yet still have a strait looking cut on the surface.


HooKooDooKu is offline   Reply With Quote
Old 04-19-2010, 09:45 PM   #3
Join Date: Feb 2010
Location: Michigan
Posts: 451
Rewards Points: 352

what makes you think all the ci pipe has to be replaced? Have you thought about just replacing the failed section?
plumberinlaw is offline   Reply With Quote
Old 04-20-2010, 06:00 AM   #4
DIY staff

Join Date: Sep 2009
Location: Kane county,Illinois
Posts: 25,728
Rewards Points: 7,174

A circular saw with a diamond blade will make the cuts--they don't need to go all the way through the slab.--Concrete cutting machines are available to rent also.

Rent an electric jack hammer to break out the concrete.

Forget the 'bridge' idea--You could not get the gravel under the 'bridges' after your new drains are installed.
oh'mike is offline   Reply With Quote
Old 04-20-2010, 08:23 AM   #5
Join Date: Nov 2007
Location: Nashua, NH, USA
Posts: 7,971
Rewards Points: 1,548

If the floor wanted to get uneven then leaving bridges will not keep it together.

I suggest the straightforward approach, cutting a strip above the path of the drain pipe.

I think that it is preferable to jackhammer both edges of the trench compared with jackhammering just one line and sledgehammering out to the desired trench width. The latter is more likely to result in undercutting where the concrete patch may fall down a little as opposed to sit atop or be locked into the sides of the trench.

While the trench is open, check for (rare) signs of the floor wanting to get uneven such as underground water flows (called underground springs if large) and consequent undermining of the floor slab. In extreme cases the sewer pipe can be suspended to maintain pitch using hangers embedded in the poured concrete patch covering the trench.

Been there done that.
The good conscientious technician or serviceperson will carry extra oils and lubricants in case the new pump did not come with oil or the oil was accidentally spilled, so the service call can be completed without an extra visit.

Last edited by AllanJ; 04-20-2010 at 08:31 AM.
AllanJ is offline   Reply With Quote
Old 04-23-2010, 01:46 PM   #6
Join Date: Apr 2010
Location: Maine
Posts: 15
Rewards Points: 10

Cutting basement floor

If your basement floor hasn't cracked and shifted already it's not going to just by cutting a strip out of it. I would hire a professional concrete cutting company. The basement floor is probably around 4 inches thick. That's a lot of cutting, dust, and jack-hammering for a DIY kind of project. Not to mention the silica in the cement dust is very bad for you. A professional Sawing company will cut completely through the concrete making you a trench where you need it and the concrete can be taken out in rectangular pieces. They will use water so there is no dust and have saws that run on compressed air, so no fumes from a motor. They will have it cut very quickly and save you a lot of time and hard work.

Patching the trenches back in after can be done with redi-mix concrete from a Concrete company or bag mix like quikcrete. This depends on how much you need to do and how you want it to look after. The redi-mix will match closer to what you have there now after it dries.


Creteexpert is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Seal Peel and Stick Tiles? Echo1 Flooring 21 06-22-2012 09:07 PM
Basement floor advice gbwillner Building & Construction 13 03-17-2009 12:04 AM
Carpet in the basement Packer Backer Flooring 16 11-03-2008 11:19 PM
Paint(?) on basement floor dissolves with water Jaybone Painting 3 08-25-2008 11:51 PM
Basement Floor Finishing, Advise Needed dbbyleo Flooring 5 04-25-2008 11:32 AM

Top of Page | View New Posts


Search Engine Friendly URLs by vBSEO 3.6.1