Monthly Archives: April 2010

Starting on the new sewer lines

It feels like we are nearing the end of a long journey. Early this year, we started with the basement sewer project by finding the old sewer lines, inspecting them, and deciphering how they worked.

We took the old sewer stack down, began to think long and hard about a new sewer layout, and finally came up with a good solution. We trenched for the new sewer lines, removed the old vitrified clay pipe, and cleaned out the grease trap.

And finally, (imaging the drum beat) everything is place to install the new cast iron soil pipe (CISP) sanitary and storm sewer. Boy, have we been waiting for this day!

It started early in the morning with the delivery of the CISP and accessories. I looked at the pile of cast iron laying in the back yard and knew that I had we had the work cut out for us over the next couple of days. Don’t think that I am mad enough to attempt the installation myself. I had professional help from Mariusz, Peter and Chris.


As with the trenching, we started the installation in the front of the basement. We removed the old check valve, which I had left in place ‘til now and connected with a non-shear coupling to the existing six inch sewer, which was coming into the building from the street.

I never would have thought that hauling around cast iron piping could be so much fun.


Raking, and no end in sight

No, not in the yard but in the basement – on the foundation walls.

Because the landscape around the house does not drain away from the building everywhere, the foundation wall had wet spots. The previous owner “solved” the problem by covering the limestone rubble foundation with cement parging, effectively trapping the moisture in the wall.

Trapping moisture in a masonry wall is always a very bad idea. Our plan is to solve the drainage problem around the house, insulate and waterproof the foundation wall from the outside, but let it breathe and dry out to the inside.

Great, except we first have to remove the parging, which was for most part a pretty painful job.

parging-removal-01 parging-removal-02

I am eternally grateful to Cathy and many of our friends who chipped away for days, until all parging was gone.

Are you hoping it goes uphill from here? Not yet, because next I have to rake out the old foundation joints so that I can repoint them. This is almost as painful as the parging job (forgive the upbeat description).

I began with the grinder, removing any cement residue and sections of hard mortar. After that I raked out all loose mortar to a depth of two to three inches at times. Last but not least I will need to wash out the joints before I’ll be ready for repointing.

I did not realize how long our foundation wall is, until I started this job! The really scary thing is that I may have to do the same job again on the outside of the foundation wall.


Grease trap cleaning

We have this big, old, ugly masonry grease trap in the basement portion of the back porch. Over the past century it received all of the waste water from the kitchens. It also received roof runoff from the downspout. Both roof runoff and kitchen waste water exited the grease trap through the main sewer.


When we took a first look at the grease trap early last year, we found a big old stinking, gooey, gunky mess with big and small chunks of grease floating everywhere. Now a year later, it still is stinky, greasy, gooey and gunky. But now it’s time to do something about it – it’s time to clean the mess. Yum!

I got myself a small paint bucket, perforated it with small slots, screwed it onto a long stick and started scooping the all that deliciousness out of the basin. Once I had most of the goo removed, I dropped a small sump pump into the pit. That worked only for a short while, because the small floating gunk clogged the sump pump screen.

Fair enough. I went to the equipment rental place around the corner and got myself a small trash pump, which got the job done, and the basin was finally empty in no time. I now could remove the old incoming sewer lines and part of the rotten brick work.


We eventually will remove the grease trap and a sump pit for the footing drains that will take its place. But that has to wait until we get to the porch rebuild. For now, I need to have the storm sewer line temporarily terminate in the basin so that it can pick up the roof runoff.

We also will temporarily terminate the footing drains in the old basin, until we install the new sump pit.


Trenching for new sewer lines

With the spread footings excavated, we now can finalize how exactly to route the sewer lines through the basement. But first we need to remove the old vitrified clay tile sewer, which we traced and exposed a while ago.

We start with the excavation for the new sewer at the connection to the existing sewer, i.e. where the existing sewer comes into the building. The elevation of the existing sewer is something we cannot change, and is thus the logical starting point.

While trenching through the basement, we make sure that the bottom of the trench steadily rises at a slope of about 2% (or about a ¼ inch over 1 foot). The slope is needed for proper waste water flow out of the building. Paying attention to and finishing the trench invert with the correct slope will make the upcoming sewer installation a whole lot easier.

Trenching for the main lines (storm and sanitary) is straightforward. Figuring out the trenching for the check valve and all basement plumbing is like shooting from the hip. It is difficult to finalize until we have all the tees, wyes, bends, and vents actually laid out.

I gave it my best bet and hoped most of it would fit the plumbing, although we may need to excavate some more during the sewer installation.


Spread footings

I am still stuck in the basement, and will be for a while. We have figured out the new sewer layout and know the scope of structural work needed for the green roof. Now it’s time to bring the shovel out of retirement.

We start with the excavation for the spread footings, which will accommodate steel pipe columns to manage the extra load of the planned green roof.

The spread footings take up some space, each four by four feet to be exact. We have to snake the sewer lines in between the existing and new footings from one side of the basement to the other.

By excavating the four by four patches first, we can determine the exact run for the new sewer lines and make sure they won’t end up under the footing.