Interior French Drains
Fixing a wet basement is a simple procedure that is generally completed in a day or two. The process is a clear one: Jackhammer around the perimeter, lay down some crushed stone, install a drain, and cement over the top. Find the lowest spot, and install a reliable cast-iron sump pump. Drain the system out of the home. Seems simple, yes?
It is simple. But bear in mind that there are many sump pump installers in the industry, and the level of quality among the different installations varies enormously. Take a look at the different components of a sump pump installation to learn more about the line between an effective sump pump drainage installation and a wet basement.
The Perimeter Drain
Interior perimeter drainage systems install along the inside wall of the foundation, usually underneath the floor. They have two goals: to intercept water as it enters through the wall/floor joint, and to collect water that may run from the basement walls.
Because interior French drains sit on top of the footing and not underneath several feet of soil, they're more resistant to clogs. However, if the installer simply installs a round PVC pipe along the exterior, your system has three weaknesses:
- Round PVC pipe is much more likely to clog than other drainage designs.
- This pipe will be very large and will require more labor, materials, and cost to you to install along the edge.
- Because PVC pipe lacks a wall flange to run alongside the wall and collect water, your installation will require a large open gap to run along the entire perimeter of the basement.
These three weaknesses combine for further problems. The gap along the edge of round PVC pipe installations not only allow humidity and odors to seep out- it also collects dust, dirt, and debris from the basement floor. This debris will further clog the pipe, which means that it will need to be serviced more often. Additionally, you will generally find out that your system has failed when the basement floods- a situation you definitely don't want!
The answer is to use a drainage system that is not round but is shaped specifically to be clog-resistant and space-efficient. Innovative new French drain products are on the market now that are designed to sit underneath the floor along the footing, collecting water without ever clogging. With some drains, a special wall flange will run up the walls along the side to collect water running down from the foundation walls with no need for a large gap along the edge to collect debris. Simply put- it's the best of every world.
A monolithic foundation consists of a two-piece foundation instead of a 3-piece one. With a monolithic foundation, the floor and footing are poured at the same time. Essentially what you have is a floor with thick edges, and those thick edges serve as the foundation footing.
In this case, it's not a good idea to jackhammer the floor, as the footing would be damaged. Instead, install a baseboard system that is permanently epoxied permanently to the floor to channel water from the floor/wall joint and walls to your basement sump pump.
Click to read more about sump pumps and basement drainage systems.