I am in a 50 year old house with iron pipe drainage. While investigating the pipe through the vent pipe connection of the washer drain we noticed the pipe to be badly corroded thereby essentially reducing the pipe diameter. We have experienced increasing overflow from the washer drain pipe when the washer dumps. I believe the best approach would be to replace the piping with PVC. I am just wanting to confirm all the watchouts in doing so. It is a pier and beam structure. I have not crawled under the house as of yet to see how big a job this is. I am assuming I can hack saw the pipe here and there and remove. Then replace with PVC using the same design and then boot it somether back towards the middle of the house. My main concern is fitting the new pipe into the existing locations. A proper diagram would be great and I do appreaciate your time and help.

Here is what Tom said a few years ago. He may have an update but it looks good to me. https://www.askmehelpdesk.com/plumbing/cutting-cast-iron-pipe-10190.html You can buy these products in most home centers. Welcome to Fernco, Inc. (http://www.fernco.com/)

Hi rcarly:

You sound like you have a good handle on this... but cutting the old stuff with a hacksaw could be pretty hard... thinking you should either purchase or rent a sawzall with bi-metal 8/10 teeth/inch blades (see pic.). Should make the cutting a lot easier... just be careful.

Ballenger said it... can use ferncos or metal banded clamps (I prefer the banded clamps... if you can find them the four band husky clamps are the absolute best)... see other pic. (ballenger posted on ferncos).

Hope that helps reduce some of the labor... ;) Keep us updated... Mark

While investigating the pipe through the vent pipe connection of the washer drain we noticed the pipe to be badly corroded thereby essentially reducing the pipe diameter. Are you saying that you went on the roof and looked down the vent, or are you confusing vent with washer stand pipe. What is it you wish to replace? Everything from the main to the roof or just the washer trap and standpipe? Let me know, Tom

If you are to replace all the piping, stay 2" pvc pipe all the way--->>> 2" drain, 2" vent, 2" p-trap, 2" dandy cleanout (I install just above the trap inline with vent (not standpipe)) and a 2" standpipe out of the trap that is between 18 an 30 inches tall. See pics. Below

You should basically just be copying what is there... but with guildelines I presented above. Let us know if you need more... Good day.