Choosing the Right Sump Pump Size for Your Basement

A sump pump

A sump pump is many homeowners' first layer of protection against leaks and moisture in the basement. Although sump pumps are generally simple to maintain, it can be difficult for homeowners to choose the right size pump.

Everyone has different needs. Some live in homes where the foundation is below the water table, and some live in areas that are particularly dry. A sump pump is not chosen based on the size of your home or basement, but based on the amount of moisture it will manage.

The horsepower of the motor is more important than its size. The strength of its motor, not its size, determines how powerful the sump pump is. You should decide which sump pump to buy based on horsepower.


Most sump pumps are sold based on the basis of the motor's power, not how big or small they are. The power of a sump pump is measured in horsepower (hp). They are usually sold in increments out of 1-whole, such as .5-horsepower, .33-horsepower, or .25-horsepower.


A .25-hp sump pump is a great deal weaker than a .5-hp pump, and a little weaker than a .33-hp sump pump. Although problems with a pump being too strong are rare, a .25-hp pump might be ideal for homeowners on a budget who do not think that a large pump is necessary for their home.


A .33-hp sump pump is standard. If your home had a sump pump installed when you bought it, chances are that it is this model.


A .5-hp sump pump removes at least 3,000 gallons of water per hour. It is one of the most powerful motors that is widely available. Although it is certainly possible to find pumps that are even stronger, there is rarely a need for the average homeowner to have a sump pump that is stronger than .5-hp. If you are still having drainage issues with a .5-hp sump pump, the problem is likely with your sump pit and not with the pump itself.

Which One Is Right for You

How much horsepower you need in your pump is based on several factors. Determine how much of your drainage system will be connected to the pump, how deep the groundwater is, how deep your basement is, and whether your foundation is below the water table. If you're unsure about any aspect of your home's drainage system, there is nothing wrong with calling in a technician for a consultation.