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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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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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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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