Monday, April 7, 2014

The external sump pump could be the solution to your wet basement

The external sump pump.

Every new home built today is built with a sump pump, it is installed in the basement or crawlspace of the home. It is installed in a sump pit, this basically is an oversized plastic pail that is located below the concrete floor of the home.

There is another kind of sump pump, it is called an external sump pump. It is installed on the outside of your home. It is installed in what is called a sump well, the sump well is located 5 to 10 feet from the outside of the home.

The well usually is made from concrete, one of the most commonly used things to form a sump well are concrete well tiles. They are roughly 3 ft wide in diameter and about to 2.5 feet high, they are manufactured in a circle and they are designed to fit on top of one another. They are excellent at holding back the ground creating a perfect place to have access to an underground pump.

You install enough concrete pieces so that there is an unobstructed well that is deep enough that it is below the house sump pump, this should put the external pump below the footings as well.

Once you have the well tiles installed, you redirect the house weepers so that they run into the external sump well instead of first going into the sump pit inside. This will cause the sump well to fill with water. You then install a sump pump at the bottom of the sump well and pipe it up and out of the sump well away from the house.

The reason that you would do this instead of relying on just the interior sump pump is because the water volume around the house is so great that the internal sump pump can’t keep up and the foundation of the house is being saturated with water. Instead of allowing the water from the outside around the house into the internal sump pump, you move the water into the sump well outside. This allows the internal sump pump to only deal with the water that is directly underneath the house.

The sump well also has the ability to hold a fair bit more water then the internal sump pit. This is a safety system so that if and when the water is overwhelming for the pump at the bottom of the well it doesn’t overflow out of the well. It contains the water inside until the pump is able to move it.

External sump wells are usually installed as a retro fit to help finished homes that have high water volume problems ease the pressure around the foundation.

Rob Abbott
Operations Manager
Village Builders Inc.


  1. Sump Pumps generally range from 1/3 to 3/4 h.p. and are rated by their maximum pumping ability in GPH (gallons per hour). A sump pump with battery backup can run continuously for 6 to 12 hours before the battery looses it's charge. This is enough to bridge most power outages. If your electricity is out longer than that, a generator could keep it going indefinitely but you'll have to make sure the sump pump is on a circuit served by the generator.Details here

  2. Hi Rob. Love all the information from the blog. Very informative. Question in regards to external sump pump. We are building in area that has high water table. The builder has advised that we should install an external sump with a French drain before he starts on the footings and then the weeping tile would be installed after that. This is what he had to do with another home in the area after lengthy delays because of the groundwater and rain this spring. It seems a little redundant to me. I can see how it would help them dry out the area to do footings etc but not sure long term if that's something that's required. The French drain/external sump is apparently my cost and a significant one at that. Any insight would be appreciated. Jeremy.

  3. hi rob, any special needs for winter on SW ontario?

    1. In what way do you mean special needs?