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Mr. Handyman How To Guide

A Solution for Flooded Basements

Sump pumps help evacuate water

Mr. Handyman has been getting many, many calls concerning wet basements this month due to the incessant rains. Typically, water leaches through the foundation on the uphill side of the house-it seems all houses in Seattle are on hillsides. While this water may find its way to a floor drain or be otherwise cleaned up, there are a number of problems we see, caused by the dampness:

• Electrical danger to people, pets and electronic equipment
• Damage to things stored on the floor
• Mold and mildew due to the wetness
• Rotting of studs and plates in finished or partially finished rooms.

There are a number of solutions to basement water, ranging in complexity and cost. One of the most common and economical is a sump pump, which we discuss here in greater detail.

What is a sump system?
A sump pump system consists of four major parts: a ground-water collection system, a sump tank, a pump and an outlet drain. Here's how they work:

Ground water is collected by buried drain rock and/or drain tile from which it drains into the sump tank (or two sump tanks, in a large house) that is buried in the basement floor.

The sump tank, also called a "basin," "crock," or "sump pit," may be made of clay, tile, steel, concrete, fiberglass or polyethylene. Though they vary in size, standard tanks are about 18 inches in diameter and from 2 to 3 feet deep. Normally, a tank is located at the low point of the basement. Most tanks have a hole in each side for incoming drain tile and all have a sturdy cover. When ground water fills the tank to a given level, a float or some other switching device activates a pump. (Though much less common, some pumps are controlled manually.) Many pump manufacturers sell polypropylene or fiberglass tanks custom-fitted to their pumps.

Standard sump pumps are electric, powered by household current. There are two main types: submersible and pedestal. A submersible pump is completely concealed inside the tank. A pedestal model has a column that protrudes up through the tank's cover; the motor is mounted on the column, above the floor level. Both types draw water in through a filter trap (this should be cleaned periodically). They pump water out through a discharge pipe and/or hose. As soon as an automatic pump empties the tank to a certain level, it's motor turns off.

If it's connected to a sewer, the discharge pipe has a check valve and may have an anti-siphon device to prevent back-flow. Or the discharge pipe may simply connect to a hose that carries the water well away from the house. Codes in most areas dictate where the water must be discharged.

Sump pump buying options
You can buy a new sump pump through do-it-yourself retailers, plumbing wholesalers or waterproofing contractors. The prices range from about $60 to $500 or more, depending upon quality and features.

First decide between a pedestal and submersible pump. A submersible is out of sight and earshot, an important advantage if the basement is used as a primary living area. It's also much safer if there are children in the house.
But pedestal pumps are less expensive and last longer. Because submersibles sit in water a good deal of the time, they have a life span of from 5 to 15 years. Pedestals, on the other hand, may continue to operate for as long as 25 or 30 years. (Because a pump's life is closely related to the conditions and frequency of its use, most manufacturers offer limited 1-year warranties.) Pedestal pumps are also much easier to repair.

Automatic switches come in several types, including floats, diaphragms and mercury switches. It doesn't really matter which type you choose--but be sure to choose one of them. By the precepts of Murphy's Law, if you put in a pump with a manual control, you won't be home to turn it on the next time your basement begins to flood. An automatic switch can protect the pump, too. Most pumps burn out if they run "dry" for too long. An automatic switch prevents this from happening.

Price is directly connected to a unit's strength. Almost without exception, the least expensive models are also the weakest. A sump pump is measured by horsepower--pumps range from 1/6 to 1/2 HP.

But more important is the number of gallons per minute (GPM) or gallons per hour (GPH) a pump will move. This capacity is a factor of both the pump's efficiency and the "head" or "lift"--that is, the vertical distance from the bottom of the sump to the highest point of discharge. A pump may advertise "2400 GPH" but this may be measured at a 1-foot head. At a 5-foot head, that figure might drop to 2100 GPH and at 10-feet, 1800 GPH. Also note whether the pump is strong enough to pass small solids, such as leaves and twigs.
Materials that make up a pump also affect price. Look for parts and housings that won't corrode--cast bronze, alloy, stainless steel and epoxy-coated cast iron housings are favorable; avoid sheet metal. Polypropylene and related plastics are used in all grades of pumps.

Pay attention to the power cord's length, too. They come with 5, 10, 15, 20 and 25-foot-long power cords. Extension cords shouldn't be used with sump pumps.

Back-up sump pumps
You can also buy pumps that will operate even when the electrical power goes out--in a thunderstorm, major flood or brownout, for example. Most of these are intended to be auxiliary pumps--used in tandem with the primary pump, they kick-in if the main pump fails. One type runs on a rechargeable 12-volt battery. Another is hooked up to the house's water system and operates by water pressure.

Whether or not you need a backup really depends on your situation--the likelihood of a power or pump failure and the damage such a failure could cause. In some cases, an inexpensive high-water alarm will suffice. On the other hand, if you're going to lie in bed on a rainy night and wonder if your new sisal-wool carpet is under water, a backup may give you more than flood protection--it may give you peace of mind.

Mr. Handyman can help
Contact Mr. Handyman to discuss installing a sump pump in your basement before the next round of winter rains. We'd love to help you avoid the inconveniences of flooding.

 

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