Buying guide for best sump pumps

A good sump pump will keep groundwater and floodwater from weakening the structure of your home. It will also allow you to maximize the use of below-ground spaces. However, choosing the right pump can be a bit of a challenge.

That's where BestReviews can offer invaluable help. We have the facilities to carry out testing that just isn't practical for you to do yourself. We discuss issues and features with trade professionals, and we review customer feedback, too.

We build a complete picture of performance and value. To ensure we're absolutely unbiased, we never take free manufacturer samples. Instead, we spend our own money and buy the same products you would. That way, you know our findings are an accurate reflection of the way each model should perform in your home.

Our five finalists offer a variety of solutions. Some are general-purpose pumps that are useful in the event of flooding. Others are designed to be installed permanently. We're happy to back each one with our independent recommendation.

If you'd like to know more about the parameters we looked at, please read the following sump pump shopping guide.

If you want to turn a damp basement into a useful storage or living space, a sump pump is a must-have piece of equipment.

Sump pump types

There is a wide variety of water pumps on the market. If you're specifically looking for a sump pump, you have three choices: manual, pedestal, and submersible.

Manual sump pump

This type of water pump comes in two forms. Either one can get you out of trouble, but neither is really practical as a full-time sump pump.

• Fully manual (hand-operated for emergency solution)

• Electric with manual activation (similar to submersible models minus automatic activation)

Pedestal sump pump

This type of water pump sits above the water line and is usually triggered by a float valve that hangs underneath. As the water level rises, the float valve rises with it and turns on the pump. If you only have space for a narrow sump pit or the pit needs to be shallow, a pedestal pump is a good solution.This type of pump runs unattended, so it’s a better option for a full-time sump pump.

Pros:

• Accessible; easy to maintain and repair.

• High-quality models last a long time

• Smaller sump pit required

Cons:

• Exposed motor

• Louder than submersible pumps

• Must keep children and pets away

Submersible sump pump

This type of water pump is designed to fit inside a sump pit. When the pit fills with water, either a float or a pressure switch activates the pump. Submersibles are quiet and mostly hidden; if you want to get the most use out of your basement, these features are particularly attractive. Submersible sump pumps are the most popular type. From here on out, that is the type we will focus on.

Pros:

• Out of sight

• Quiet

• Sealed (unaffected by dust, dirt)

• Many options
   

Cons:

• Less accessible for maintenance

• Breakdowns may go unnoticed

• Can be more expensive

Sump pump specifications

There are two major factors you need to consider before choosing a sump pump.

• Pumping Volume: Can the pump move the required volume of water the necessary height to clear the basement?

• Motor Power: Does the pump’s motor have sufficient power, without straining, to work day in and day out?

Pumping volume

Submersible sump pumps are specified by flow rate, measured in gallons per minute (gpm) or gallons per hour (gph), with the latter being more common.

Entry-level models start at 2,000 gph. The best pumps can exceed 4,000 gph.

However, these figures can be deceptive because they are for horizontal pumping. If you’re pumping water out of your basement and above ground, that water has to go uphill at some point, and this requires more effort from the pump. In that case, the volume drops, as in this example.

• 2,500 gph at zero feet (horizontal)

• 2,000 gpm at 10 feet of elevation

• 1,200 gpm at 15 feet of elevation
   

It's important to think about your entire installation before buying. If your sump pump doesn’t have a large enough pumping volume, you'll be left with standing water, which defeats the purpose. This is one situation in which bigger is invariably better. You’ll never pump “too much” volume. Once your sump pit is empty, the pump switches itself off.

Motor power

Reliability is one of the most important aspects of a permanently installed sump pump. If the motor is under constant strain, it won’t last long. For this reason, manufacturers err on the side of caution and provide much more powerful motors than you might expect to find in a device of this size. On quality sump pumps, motors with 1/3 or 1/2 horsepower are common, and that is what we recommend.

Most submersible sump pumps run off standard 110-volt household electricity, but there are some that don't. Check before you buy.

Other sump pump considerations

• Battery-Powered Backup Pump: If the power goes out, the sump pump stops working and your basement can flood. You can avoid this with a battery-powered backup pump, a secondary unit that sits beside the main pump. While slightly less powerful, high-quality models should still move enough water to prevent a disaster in your basement.

• Cast-Iron Casings: Casings are either cast iron or thermoplastic. In the past, cheap plastic covers were often criticized for their lack of durability. Modern materials are much better. Professionals we consulted still prefer cast iron as a sign of quality, but there is no longer a major long-term performance difference.

• Alarm: Some backup systems include an alarm – a visual alert – so you can tell that it's running on battery power. Separate high-water-level alarms are available if you choose to install a manual sump pump.

• Filters: You can help prevent clogging with filters. These should be cleaned when you do your regular maintenance on the pump. The ability to pass solids reduces the chances of a blockage. Sizes vary, so it's a good idea to check before you buy.

Sump pump prices

• Products called "submersible sump pumps" start at around $50. While these models will do a good job of clearing a flooded area or draining a pool, they aren’t really intended for constant use.

• A good, entry-level, permanently installed plastic sump pump starts at around $65.

• A good, permanently installed cast-iron sump pump costs around $165.

• A plastic battery-backup sump pump costs around $170.

• A cast-iron battery-backup sump pump costs from $250 to $550, depending on its specifications.

Tips

• A sump pump with a battery backup will continue to work in the event of a power outage. Running time depends on battery size and how often the pump is activated. It's unlikely to be less than 12 hours and could be as long as a couple days.

• Check your sump pump every three or four months, particularly before winter. The last thing you want during a thunderstorm or blizzard is to discover your pump isn’t working!

• If you can hear your sump pump running, but the water level is still rising, check two things:

  • Is the outlet pipe blocked or iced up?

  • Is there an air lock or blockage in the outlet valve?
     

If you have modest do-it-yourself skills, both are relatively easy to clear. If in any doubt, call a qualified professional.

• If the pump is running but there's no water, the float or pressure switch that activates it could be clogged. This is a problem with some cheaper sump pumps. High-quality models have better casings to prevent this situation. Regular maintenance is a sensible preventative measure.

Concrete is porous. If water gets into your foundation and freezes, it will expand. This weakens the structure and can also cause the building to lean or twist or internal walls to crack or separate. Plumbing and sewage pipes can also be damaged.

FAQ

Q. Do I need a sump pump?

A. Not everyone needs a sump pump, but figures from the American Society of Home Inspectors show that over 60% of homes are at risk from excess moisture. Groundwater can eventually damage concrete or cement foundations. If your basement floods, it can cause thousands of dollars worth of damage. Mold on basement walls is a good indicator that water levels are too high. A sump pump can be an efficient, low-cost solution to this kind of problem.

There is another factor: a sump pump may be required for some homeowner insurance. Consult your broker or check your policy details.

Q. How long will my sump pump last?

A. That depends on the quality of the pump you buy and the amount of work it has to do. Experts tell us that a good pump can last up to a decade. The pump’s working life will be extended by following the regular maintenance program suggested by the manufacturer.

Q. Are sump pumps noisy?

A. Cheap sump pumps can vibrate, causing an annoying buzz, but in general, your sump pump should be quiet. A sump pit cover can help reduce the sound of the water being pumped. If you own a good-quality pump and it still makes noise, there could be another cause.

• Water running through discharge lines (outflow pipes) can be noisy. The path should be as straight as possible. If bends are necessary, use two 45° joints rather than one 90° joint.

• If the discharge line isn’t properly connected to the pump, it can vibrate and cause noise.