Perimeter drains can protect your home from water damage, and keep your basement and belongings safe and secure. They give homeowners peace of mind, especially when there is a big rainfall or snowstorm but, perimeter drains do come without their own set of problems.
What is a perimeter drain?
A perimeter drain or exterior drain tile system, is a drainage system that is designed to prevent water from seeping into your basement. It carries the water accumulated from heavy rainfall or melting snow, away from your foundation, keeping your basement or crawl space dry.
Problems with perimeter drains
The first step of having a perimeter drain installed is excavation of the perimeter of your home. This means that any sidewalks, walkways, patios, flower beds or bushes that line outside of your house will need to removed so that a trench can be dug. This excavation requires a lot of work. If you have any pavers, or concrete sidewalks, they will need to be demolished, hauled off site, and disposed of. Once the perimeter drain is installed, whatever hardscaping you want replaced will need to be redone.
When excavating the trench, the trench must be as deep as the foundation or crawl space. The deeper the trench, the wider the working area (for the safety of the contractor), and the more soil needs to be excavated. All of these factors increase labor, and time spent on the job. This is why it is recommended that drainage is installed before getting any landscaping done, such as patios and flowers beds getting placed.
Working area around home
When installing a perimeter drain system, the working area around your home needs to be at least 10-20’. To ensure that the trench is getting dug deep enough, machines need to be used, and when machines are used to dig, the area around them needs to accommodate them moving around. As well, the soil that is being excavated needs a place to sit while the pipe is being installed. If there is not enough room for a machine and the soil, the excavated soil will need to be put somewhere else. This means that another machine (or wheelbarrows) will haul the soil from the perimeter (side, back or front) of the yard, to the front yard or the street. Once the perimeter drain system is installed, the excavated soil will then have to be hauled all the way back to the backyard or side yard to fill in the trench. This is a messy way to do things, and adds more labor, machines, and time to get your trench built.
Perimeter drain outlet
Your perimeter drain needs a proper outlet, or discharge station, for the water that the pipe is carrying away from your house, to end up in. All of the pipe around your house should tie into a sump. A sump is a large 3-4’ diameter concrete container that sits flush to the ground. There are inlet pipes, and outlet pipes that connect to the sump, and the outlet pipes carry the water to either a storm drain, ditch, rock pit or pond. If your drainage system ends up going to a city ditch that is far away from your yard, you may end up needing to have a trench line going all the way to the ditch, which adds labor, material costs and time to your perimeter drain project.
Adding drainage after your landscaping is complete
Anytime a project is done where there is existing landscaping, it makes it hard to do an installation, because anything that is in the way will need to be addressed before the installation can begin. If there are any walkways or concrete sidewalks, they need to be removed and disposed of before a new system can be put in. This can be less than ideal if your hardscape project is only a couple years old.
The most common problem with a perimeter drain is the drain getting clogged from dirt and debris. The clogged soil can damage your perimeter drain pipes, and the water will have nowhere to do. This excess of water can cause problems like seepage and cracking, due to the pressure it is putting on your home’s foundation.
These problems may seem stressful, but proper planning and timelines ( like having your drainage system installed before landscaping) can allow your project to go quicker and smoother, and will allow you to have the peace of mind that your property is safe a little sooner.