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Jeff in Texas
replacing clay sewer pipes

I am seeking advice on replaceing my 50+year old clay sewer pipes. My plumber offered to do it for only $2800.00. I would perfer to save the money and do it myself.

The distance from the house to the city tie-in is approximately 30 feet. Home Depot has 10 foot, 4" PVC pipe for $8.50. A ditch witch rents for about $100.00. The permit is $40.00. I am estimating about $100.00 for other items.

Can anyone offer advice on what I should expect. I always try to expect the unexpected.

Timothy Miller
Re: replacing clay sewer pipes

Hi, how deep is the currant pipe? Are you going to hand dig to expose the pipe and how good of digging is your soil? Tree roots and other pipes may be in you way..

Re: replacing clay sewer pipes

If you choose to do this work there are several things to coinsider when doing this type of job. You should check with the city to find out what their requirements are for sewer line replacement. The city may require an additional excavation or encroachment permit to dig in the city right of way and an inspection of the installation. The city will be able provide their sewer lateral trench detail showing their pipe bedding and installation requirements. You should also consider trench safety equipment any time that you are working in a trench.
If you choose to hire someone to do this job, I would reccommend that you get a bid from at least three different contractors, I think that you will see a big price difference between the bids.
The city may also be able to recommend some contractors that perfome this work at reasonable prices.

Re: replacing clay sewer pipes

I agree with the safety part of it. Any trench deeper than 4' can collapse. So be careful.

Also, you will have to connect from your old pipe to the new pipe. The requires a Ferno (an elastomeric coupling). It looks like a big black rubber coupling fitting with two (2) radiator clamps at either end to tighten down for connection. Since sewer is not a pressurized system, this works. SOme underground plumbing codes require a Husky Band. This band has a metal shielding and can have four (4) of the radiator clamps on it.

Make sure the grade is correct. 4" = 1/8" per 1" slope.

Good luck. Process of elimination.

Re: replacing clay sewer pipes


You didn't mention what problems you are having now that you would want to replace the clay pipe (constant clogging, roots in pipes, etc.)---clay pipe is usually 5" in diameter for residential sewer lines.

This means that 6" PVC (plastic) sewer line is widely used & will connect to the clay pipe near the property line so you don't have to go into the middle of the street to tie into the city main.

SDR-35 ASTM-D-3034 at 6" with built-in neophrene gasket seals on both ends is widely used---comes in 14' sections & costs approx. $1 to $2/foot.--pipe is 3/8" thick & thus can take a roto rooter without any problem should the need arise.

Pipe, elbows & street els widely available at local pipe supply houses in your area; consult the Yellow Pages under "Pipe" or "Pipe, Plastic"---none of the big box stores carry these items, they would be much more expenive if they did.

Googe "SDR-35""sewer pipe" for more sites.

SDR-35 can be cut with a circular saw with a metal-cutting blade, can be welded with standard PVC cement & couplings are available.

Clay pipe can be cut with a circular saw with a masonry-cutting blade---make sure you maintain at least a 1/8" pitch towards the city sewer main at all times.

This would enable you to tie into the old work, perhaps at the half way point, allowing you to dig no deeper than a 4' trench---this stuff is excellent for sewer lines--- will last for 100 years---I love it!


Re: replacing clay sewer pipes

A few more tips:

  1. When you go to get the permit, have a sketch showing the locations of your house, the street, any trees, your property lines, and what you plan to do. Include measurements of distances between things.
  2. Install a two-way cleanout next to the house where the pipe comes out. This is probably required by code, but even if it isn't it's a good idea as it will allow servicing of the pipe to the street without having to enter the house.
  3. Lay pipe with the writing up so the inspector can see it.
  4. Where the branch line connects to the sewer main can be quite deep. Be careful about possibility of a trench cave-in, which can be deadly. Shoring may be necessary.

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