Solving Water in the Basement

You're enjoying yourself at the company dinner party when the host pulls you aside to say your teen-age son is on the phone. When you pick up the line, John Jr. informs you that the water is really coming into the basement this time.

With the exception of an occasional problem with an underground spring, the source of 95 percent of all water in the basement problems is rain from the sky. The remaining percentage may be due to a high water table or sewer backups.

The primary cause of water in the basement is poor grading outside the house where the slope of the yard grade is toward the house. Detached or failed gutters and downspouts that do not divert water away from the walls of the house also contribute considerably to water problems.

The solution to water in the basement problems caused by poor grading is easy to understand, but may be costly to implement. But, a solution is necessary.

To identify the problem areas, walk around the house and look for any depressions in the soil. The common places are at downspouts and the walls close to the house, especially those adjacent to window wells, chimneys and concrete slabs or steps.

When you locate the depressions or low spots, you must remove the soft soils and then create a positive slope away from the house with a dense soil, such as clay. Then bring back the soft soil on top of the clay. Soft soils may include top soil, sod or mulch. These soils have very high air content and tend to hold water like a sponge. Typical top soil is approximately 40 percent air.

Also, be sure to remove any sand or stone away from the walls of the house, as water will filter through the sand or gravel, accumulate at the bottom and eventually find an opening in the masonry basement wall.

Regrading addresses the cause of the problem. If landscaping,

flower beds or concrete patios or walks have to be replaced, it may not be economically practical to regrade. A generally accepted solution is to install a drainage system with a sump pump in the basement/crawl space to receive water that enters the area. A sump pump will discharge water that enters. However, it does not address the cause of the problem. In addition, the water that enters still causes high humidity, which, in turn, affects your comfort level and may cause mold to develop.

In the majority of cases, regrading is less expensive than a drainage system and sump pump because only low areas have to be addressed. Regrading may cost $20 to $30 per linear foot if flower beds or shrubs do not inhibit work. And, in most cases, only a portion of the perimeter has to be addressed. Regrading costs may range from a few hundred dollars to address low areas or downspout extensions alone to $3,000 to $3,500 to regrade the perimeter for a house that is approximately 30' by 35'.

The drainage system, called a hydrostatic pressure relief system, typically goes around the perimeter of the basement. The cost is generally $25 to $35 per linear foot, plus $400 to $500 for the pump, crock, discharge piping and electric outlet. If your home has a 30' x 35' basement, the cost for a French drain may be $4,000 to $5,000.

Both procedures can be expensive, but these situations do occur in homes. The cost may not allow you to go to dinner parties with the most expensive dress or jacket, but you will have peace of mind in knowing that John. Jr. won't be ringing your host's phone to tell you he's ankle deep in water.

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The Cause and Solution to Your Condensation Problems

Condensation is caused when warm, moist air moves into a cooler air space or comes in contact with a cooler object. The warmer the air is, the more ability it has to hold water. The cooler the air is, the less ability it has to hold water (i.e., when warm, interior air comes in contact with a cold surface, such as a metal window frame or cold water pipe, the vapors in the air turn to liquid on the colder surface).

In an attic in the winter, moisture or ice may form on the roofing nails and the roof sheathing for the same reason.

Mold/fungus develops in bathrooms when vapors permeate through the surface of drywall or plaster and turn to moisture before it exits the other side of the wall material. This is due to the change in temperature between the living space (or warm side of the wall or ceiling) and the exterior (or cold side of the wall or ceiling).

On milder days or milder climates, it is less of a concern because the temperature differential between the inside and outside is not far apart. The solutions are ventilation, additional insulation, or stopping the permeation of vapors through the wall/ceiling material. In existing situations, access is typically difficult for proper ventilation or insulation. So the simplest approach would be to paint the wall and ceiling surfaces with a material that would significantly reduce or stop the permeability of vapors. Most enamels or hard-finish paints will do a good job controlling or reducing the amount of vapor which may pass through the wall/ceiling surfaces.

The best way to ventilate an attic:

The air in attics is warmer than the outside air in summer or winter. It is obvious how warm attics are in summer, but it may not be so obvious in the winter. Assuming the outside temperature is 35 degrees, the thermal loss from the house will raise the attic temperature 5-10 degrees, depending on insulation, wind, etc. Based on this information, the air in the attic will always be lighter than the outside air because it is warmer.

The best way to ventilate an attic would be with high-low ventilation because the only condition we can be sure of is that warmer air will be lighter and has a tendency to rise.

With high-low ventilation, the warmer air rises out of the high vents, preferably ridge vents, and this air is replaced by cooler air from low vents, typically soffit vents.

The amount of air and the speed it moves is dictated by the temperature difference between the attic space and the exterior. This is called thermal convection. When the ventilation is correct, mother nature will control the air changes based on the temperature differentials and mechanical help is unnecessary.

General criteria for improving attic ventilation:

1) For every 300 square feet (SF) of attic floor space, you need at least one (1) SF of clear air. If the clear air is not distributed 50% high and 50% low, you will need additional ventilation.

2) Louvers and vents are typically only 50-60% of their total measurement in clear air. Be sure to calculate this when you buy these appliances.

Note: If you cannot develop high-low ventilation, you will have to increase the horizontal or high ventilation by 100% or more, or approximately two (2) SF plus for every 300 SF of attic floor space.

Without a proper vapor barrier, it may be necessary to have considerably more ventilation.

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Installing Hardwood Floors

Hardwood flooring can be an excellent addition to any home. Often, installation of hardwood floors is done over linoleum tiles which themselves are over top of concrete or some other surface. Using the proper techniques and materials, this installation can be done effectively.

There are hardwood floors made that can go (almost) directly over concrete -- and that would include the installation over linoleum tiles. And while they probably work all right for one’s application, they do have some drawbacks. It’s important to know the difference between these floors before you plunk any money down.

First of all, you probably shouldn’t use conventional hardwood strip flooring for these areas. It’s not rated for below-grade installation. As you probably know, strip or plank flooring is made of solid wood about 13/16" thick. This thickness is its strength -- and in some ways its weakness. You can sand a solid wood floor several times when it becomes worn, and it should last 30 to 50 years if it receives even minimal upkeep. That’s the good part.

However, solid wood floors are somewhat vulnerable to humidity changes and moisture conditions in the areas in which they are installed. If the rooms to be covered with wood flooring are in the basement, this type of flooring would not be a good choice -- even if a plywood subfloor is installed first. Humidity in the air and moisture seeping up from the concrete floor below could cause the flooring to swell and buckle. And frankly, I would be concerned about the subfloor picking up moisture and swelling as I would about the flooring itself.

There are some pre-finished, glue-down laminated hardwood floors that are rated for below-grade installation, but these also need to go on a plywood subfloor. Laminated floors are made like plywood. A thin veneer of hardwood covers a cross-laminated sub-base, then the top surface receives several coatings of durable finish.

The "pre-finished’ feature is a big selling point to laminated floors. One doesn’t need to go through the mess or expense of renting sanding equipment or hiring out that aspect of the job.

However, on the down side, the veneer on laminated floors is thin and you can’t sand it if it gets worn. You’ve got to be observant when the surface is starting to wear. You can renew the finish several times, but sanding scratches and gouges is out of the question. Most laminated flooring is thin - 5/16 to 1/2 inch - and is glued, rather than nailed, to the subfloor.

The third choice is probably the best -- a "floating" floor. Floating floors were originally developed in Europe and have a good track record there. In fact, until recently, the only floating floors you could buy were imported.

Floating floors are another laminated product, although the top layer of veneer is usually thicker -- about 1/8" -- than the top layer on glue-down laminated floors. The "float" in floating floors comes from the installation procedure. You don’t nail or glue these floors down. You just glue the tongues and grooves together over a 1/8" thick foam pad. Baseboard around the perimeter of the room keeps the edges down, and the foam provides the floor with a little bit of "give."

Because the floor is not nailed or glued to anything, a floating floor is free to expand and contract as a unit with moisture changes in the room.

To be safe, lay a sheet of 6 mil plastic over your tile floors first, then the foam pad, then the flooring. The plastic will act as a vapor barrier and would help prevent moisture from reaching the flooring. Laminated flooring of all types is more stable than conventional solid wood strips -- in other words, it doesn’t take on or give up moisture as readily as does solid wood -- but it is still to your advantage to keep it from undergoing extreme cyclical humidity changes.

The bad news about floating floors: They’re not inexpensive. You can spend around five to eight dollars a square foot for the materials needed to install a floating floor.



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