(Newswire.net — November 13, 2021) —
In Toronto, the aging residential housing stock will force many homeowners to restore their sanitary sewer line or storm drain. This work, which is quite expensive, requires it to be carried out in accordance with the rules of the art using various techniques.
There are three main techniques for restoring a residential sewer line. The first is to excavate and replace the entire pipe or part of it with a new one. It is the most expensive technique.
The second method consists of inserting a sheath made of resin into the existing pipe. The sheath can be installed on a part or on the whole of the pipe. This last technique has the advantage of being carried out without excavation and without a permit from the city, which reduces costs and avoids having to redo the earthworks.
Finally, there is a third technique called “insertion”. It involves inserting a pipe into the damaged sewer line. “This technique, little used today, has the disadvantage of reducing the diameter of the pipe by about one inch and thus slightly reducing the efficiency of wastewater evacuation”, explain experts, Excavation representatives. AqualuxDP Toronto, a company specializing in sewer repair, among others. Since it is little used, the article will only cover the first two techniques mentioned.
Replacement by excavation
This method initially requires a permit from the municipality. It will be preferred if the pipe is deformed or damaged due to ground movements or the presence of tree roots. Before starting any work, turn off the water and then contact drain repair Toronto experts to find out if there are gas or other pipes in the soil to be dug.
A camera inspection is then carried out. A rigid cable at the end of which is a camera allows this work to be done.
The next step is to perform a leak test. This test is done with balloons and air. Some cities, such as Levis, require this test to be carried out with their own inspectors. Others, like Toronto, allow accredited companies to do the work. The results of these tests will determine the type of intervention to be done, depending on the severity of the damage to be repaired or the need for a pipe replacement.
Upgrading
If the sewer pipe needs to be replaced, it is mandatory to bring it up to standard. Now is the right time to take this opportunity to install a backflow preventer on the new sewer line as well as a storm drain to its right. This rain pipe will be connected to the city network or to a rainwater retention basin. It is also a good time to also check if it is necessary to replace the french drain around the house, or even install one when there is none.
Most of the time, the sewer line will be replaced by SDR-28 PVC pipe. For the storm sewer, it will be an SDR-35 pipe. Cast iron is still installed in some residences
Another particularity, in Laval, the installation of a backflow preventer is prohibited on the main connections. A very questionable regulation who would like to see it amended in order to introduce new technologies.
As for the storm drain, each municipality has its specific regulations. Some require the installation of a membrane around the drain, others require the installation of a chimney from the drain in order to facilitate cleaning.”
When examining the drain, there is often an accumulation of Iron ocher which can interfere with the proper functioning of the system. To correct this problem, it is possible to clean the drain using a pressurized water jet. But if it is too old, it will be better to change it completely.
In the event that the French drain needs to be changed, Experts advise to avoid the use of the sheathed drain, which can become clogged, and of the pipe sold commercially which has only three rows of holes. And since it will be necessary to excavate the entire perimeter of the house, you might as well take the opportunity to check the condition of the foundations, repair them if necessary, and waterproof them.
Replacement by sheathing
The second sewer repair technique is sheathing. This technique is not recommended if the pipe is too damaged. That sheathing is rarely a so-called structural technique. It cannot therefore replace a heavily damaged cast iron pipe. However, when appropriate, it is faster to perform, less expensive and durable (at least 25 years durability).
Aqualuxdp techniques or not, sheathing is done almost always in the same way. “At the start, we do an inspection by camera.. Next, the line is cleaned mechanically or with high water pressure (2,500 lbs) if the interior is very greasy. Then we go back to the camera to make sure the pipe is clean. “
Then comes the sheathing. First, a mandrel of the length necessary for the repair is laid out on a flat surface. Then, it is coated with a resin mixture. Each business has its own mix. It’s recommended to use three different resin recipes depending on the length of the pipe to be repaired. In the case of Drain expert, it is a mixture of epoxy and fiberglass. This mixture is then surrounded by a polyethylene in order to protect it.
The next step is to insert this mandrel into the sewer line using a winch. Once well spread in the pipe, we proceed to cooking. This operation consists of injecting steam into the mandrel in order to make it swell and allow the mixture to harden. It takes 45 minutes to an hour, depending on the length and size of the pipe. The final step is to remove the mandrel from the pipe. The liquid solution will then have rested firmly on the walls of the pipe while only reducing its diameter by one-eighth of an inch.
The sheathing offers several advantages: it resists the acids present in detergents unlike cast iron pipes, it completely blocks the development of the roots and it eliminates all joints since the resin mixture is directly supported by the walls.
In Montreal, sheathing is very popular, since during a pipe repair, it is the customer who is responsible for the costs up to the city’s main pipe, in the middle of the roadway. “If he had to excavate and replace his entire pipe, it would cost him $ 20,000 while the sheathing costs only about $ 7,000”, experts estimate, who however believes that the most durable solution of all. is the excavation and replacement of the pipe.
So, excavation-replacement or sheathing? It will often be the client’s budget that will determine the technique to be used.