80 yr old home..advice on rebuild of entire plumbing system... snake main lines?

[TOTOtalitarian]

Gents
I have an 80 yr old home in southern calif... built in 1929.
All copper lines installed.
I had all new drain lines from all sinks and tub, shower replaced with ABS down to the main 4 inch line.
Most of the drain lines were pretty clogged.
The question is what suggestion do you have for the cast iron 4 inch main line.
I am asking the plumber to snake the remaining with a wide cutter.
Are there any particulars I should request he do beside this ?
My goal is to not have to hassle plumbing clogs for years to come..... I am having two Toto Drake toilets installed.
What am I missing?

Thanks for any advice you may give

 

[Basement_Lurker]

While cast iron really is a premium piping material to use, the problem with it is that over time it will build up pipe scale. I assume that replacing the main is not an option, so even if they do use the proper attachment, the inside of the pipe will always be rough, and there is the possibility that sections of the pipe have deteriorated enough that cabling it will destroy what's left...

 

[Sponsor]

 

[hj]

One problem with snaking the line, if it is NOT plugged, is that all the debris which is scraped off will just lie in the bottom of the pipe, because there will NOT be enough water flow to flush it out as it is dislodged, and it will be too "heavy" to flush away with normal usage. I seldom advise snaking lines as a "preventive measure", that being one, of several, reasons.

 

[TOTOtalitarian]

Not trying to second guess you ....

Thanks , your points totally make sense,......as my goal is to try to get this entire system to be as close to " trouble free" as possible, ....
If I have them use 3" cutter or smaller and insure that a water hose full blast is used to provide plenty of water flow to flush out the gunk ?....
Does that make sense ? or ?? it is 80 yrs old cast iron and I respect your opinions.
I just know that the 2.5 inch lines were pretty clogged .

Thanks

 

[Jerome2877]

Have a camera run through the line to determine the best action to take. A jetter will clean the pipe if there is build up but this is not as common on the larger pipe as they have more volume running through them. Augering a main that has no solid blockage won't do much except possibly damage the pipe.

 

[TOTOtalitarian]

Ok, here is the latest..... after installation of all the new drain lines to the original cast iron 4 inch main, we had a blockage...... I opted to have the plumber replace all of the cast iron main line under the house with ABS. All of the main line under the house was replaced up to about 2 ft from the front of the house ......we assumed all would be great, but, we still have a blockage.... I have asked the plumber to replace 25 more feet outside the house up to the concrete sidewalk. (we wont replace the sewer line from under the sidewalk to the city main) There will be around 15 ft from that sidewalk to the main...... Does anyone have any suggestions for the last 15 ft that wont be replaced ? I have asked that on Friday, the plumber snake/cut the last length of original pipe left......... Any thoughts, things to look out for ? Thank you all for your guidance.

 

[Jerome2877]

Well not that it was a bad idea to replace 80 year old cast under the house but I would bet that the problem was outside the whole time. If a camera had been run down the line you would know the condition of the entire pipe and could then decide on a course of action. This is always the first step we take before just replacing pipe.

Are you responsible for the last 15 feet under the sidewalk? Normally this would be city property and it would be their problem, however some places are different and consider you responsible up to the main.

 

[hj]

You seem to be nickle and diming the repairs and trying to sneak up on a problem. I would find out WHAT and WHERE the problem is FIRST, and then fix it whatever it takes. But NOT change "this section" and if you still have a problem, replace "the next section", then wait to see if the problem goes away. Doesn't the plumber know HOW to unplug a line without replacing it?