Water Intrusion - Basic Waterproofing

Basic Waterproofing for Basements

by Nick Gromico and Ethan Ward

Water Damage Concerns

Basements are typically the area of a structure most at risk for water damage because they are located below grade and surrounded by soil.  Soil releases water it has absorbed during rain or when snow melts, and the water can end up in the basement through leaks or cracks.  Water can even migrate through solid concrete walls via capillary action, which is a phenomenon whereby liquid spontaneously rises in a narrow space, such as a thin tube, or via porous materials.  Wet basements can cause problems that include peeling paint, toxic mold contamination, building rot, foundation collapse, and termite damage.  Even interior air quality can be affected if naturally occurring gasses released by the soil are being transmitted into the basement. 
Properly waterproofing a basement will lessen the risk of damage caused by moisture or water.  Homeowners will want to be aware of what they can do to keep their basements dry and safe from damage.  Inspectors can also benefit from being aware of these basic strategies for preventing leaks and floods.
Prevent water entry by diverting it away from the foundation.

Preventing water from entering the basement by ensuring it is diverted away from the foundation is of primary concern.  Poor roof drainage and surface runoff due to gutter defects and improper site grading may be the most common causes of wet basements.  Addressing these issues will go a long way toward ensuring that water does not penetrate the basement.

Here are some measures to divert water away from the foundation:

• Install and maintain gutters and downspouts so that they route all rainwater and snow melt far enough away from the foundation of the building to ensure that pooling does not occur near the walls of the structure.  At least 10 feet from the building is best, and at the point where water leaves the downspout, it should be able to flow freely away from the foundation instead of back toward it, and should not be collecting in pools.
  
• The finish grade should be sloped away from the building for 10 to 15 feet.  Low spots that may lead to water pooling should be evened out to prevent the possibility of standing water near the foundation.
  
• Shallow ditches called swales should be used in conditions where one or more sides of the building face an upward slope.  A swale should slope away from the building for 10 to 15 feet, at which point it can empty into another swale that directs water around to the downhill-side of the building, leading it away from the foundation.

 

Repair all cracks and holes.

If leaks or seepage is occurring in the basement's interior, water and moisture are most likely entering through small cracks or holes.  The cracks or holes could be the result of several things.  Poor workmanship during the original build may be making itself apparent in the form of cracks or holes.  Water pressure from the outside may be building up, forcing water through walls.  The house may have settled, causing cracks in the floor or walls.  Repairing all cracks and small holes will help prevent leaks and floods.

Here are some steps to take if you suspect that water is entering the basement through cracks or holes:

• Identify areas where water may be entering through cracks or holes by checking for moisture, leaking or discoloration.  Every square inch of the basement should be examined, especially in cases where leaking or flooding has not been obvious, but moisture buildup is readily apparent.
  
• A mixture of epoxy and latex cement can be used to fill small hairline cracks and holes.  This is a waterproof formula that can help ensure that moisture and water do not penetrate basement walls.  It is effective primarily for very small cracks and holes.
  
• Any cracks larger than about 1/8-inch should be filled with mortar made from one part cement and two parts fine sand, with just enough water to make a fairly stiff mortar.  It should be pressed firmly into all parts of the larger cracks and holes to be sure that no air bubbles or pockets remain.  As long as water is not being forced through basement walls due to outside pressure, the application of mortar with a standard trowel will be sufficient if special care is taken to fill all cracks completely.
  
• If water is being forced through by outside pressure, a slightly different method of patching with mortar can be used.  Surface areas of walls or floors with cracks should first be chiseled out a bit at the mouth of the crack and all along its length.  Using a chipping chisel and hammer or a cold chisel, cut a dovetail groove along the mouth of each crack to be filled, and then apply the mortar thoroughly.  The dovetail groove, once filled, should be strong enough to resist the force of pressure that was pushing water through the crack.

Apply sodium-silicate sealant to the walls and floor.
Once all runoff has been thoroughly diverted away from the foundation, and all cracks and holes have been repaired and no leaking is occurring, a waterproof sealant can be applied as a final measure. 

Sodium silicate is a water-based mixture that will actually penetrate the substrate by up to 4 inches.  Concrete, concrete block and masonry have lime as a natural component of their composition, which reacts with the sodium silicate to produce a solid, crystalline structure which fills in all the microscopic cracks, holes and pores of the substrate.  No water vapor or gas will be able penetrate via capillary action because the concrete and masonry have now become harder and denser from the sodium silicate. 

Here are some steps and tips for its application:

• Special care should be taken when applying sodium silicate.  It is an alkaline substance and, as such, can burn skin and eyes if it comes into contact with them.  Inhalation can also cause irritation to the respiratory tract.
  
• Sodium silicate must be applied only to bare concrete, concrete block or masonry that has been cleaned thoroughly and is free of any dirt, oil, adhesives, paint and grease.  This will ensure that it penetrates the substrate properly and fills in all microscopic cracks.  It can be applied using a garden sprayer, roller or brush to a surface that has first been lightly dampened with a mop or brush.  Apply two to three coats to the concrete, waiting 10 to 20 minutes between each application.  Concrete block and masonry will take three to four coats, with the same 10 to 20 minutes between applications.  Any excess should then be wiped away.  Sodium silicate should not be over-applied or it will not be completely absorbed by the substrate, leaving a white residue.
  
• Paint can then be applied without fear of water vapor getting trapped between the paint and the wall, which could eventually cause blistering and peeling.  Adhesives for tile or floor covering can also be used more effectively, once the substrate has been sealed.

Diverting water away from foundations so that it does not collect outside basement walls and floors is a key element in preventing flooding and water damage.  Ensuring that any water that does end up near basement exteriors cannot enter through holes or cracks is also important, and sealing with a waterproof compound will help prevent water vapor or gas from penetrating, as well.  By following these procedures, the risk of water-related issues in basement interiors can be greatly reduced, protecting the building from damage such as foundation rotting, mold growth, and peeling paint, as well as improving the interior air quality by blocking the transmission of gasses from the soil outside. 

From Basic Waterproofing for Basements - InterNACHI http://www.nachi.org/waterproofing-basements.htm#ixzz2tJg2dCKw

Space Heaters

Energy-Efficient Space Heaters

by Nick Gromicko and Ethan Ward

Why use space heaters?

Small, portable space heaters are often used when the main heating system is inadequate, or when it would be too costly to operateor install central heating. They can also be useful to supplement adequate central heating in certain instances, such as heating one room that will be primarily occupied while lowering the thermostat on the central system so that heat is not wasted in unoccupied rooms. In some cases, it is possible to lower total heating costs by up to 10%, as well as reduce CO2emissions by up to 800 pounds, by using space heaters in this manner.

Different Types of Space Heaters

Understanding some of the differences between the types of space heaters and how they work can be helpful when deciding what the most efficient and effective options are for a given situation. Below are descriptions of some of the main types of heaters available:

• coil-based convection heaters: This type of heater uses a fan to push air into a room that has been heated internally by passing through hot metal coils. These heaters utilize a safety mesh in order to ensure that nothing in the room will come into contact with the internal heating elements.
• ceramic-element heaters: This type is generally considered safer to operate than a coil-based unit. Since the ceramic core is larger than heating coils, these units can operate at a lower temperature while providing an equivalent amount of heat that spreads over a farther area. This type of heater is also able to maintain a higher temperature for a longer period of time compared to a coil-based unit, which makes it more efficient.
• oil-filled radiators:These heaters are highly efficient and operate silentlybecause they do not use a fan. Instead, they use fluid contained in a permanently sealed radiator apparatus, which does not ever need to be refilled. The oil is heated within the unit, and the heat from the oil then radiates into the room. Once heated, the oil will continue to graduallyrelease warmth into the room even when the internal heating element is turned off.
  
• halogen lamp heaters: Energy-efficient halogen bulbs are used in these types of space heaters to provide instant warmth at the touch of a button. They are made safe by employing safety grilles and cool cabinets, and can be especially appropriate in areas where small children or pets are of concern.
  

Estimating the Cost of Operation

The operational costs of space heaters depend on the type of heater in use, as well as the room it is being used to heat. "Kilowatts x Rate x Time = Cost" is a useful formula, in general,to determine how much a heater will cost to run. Here is how the formual breaks down:

• kilowatts: the setting of the heater. Divide watts by 1,000 to get kilowatts per hour;
• rate: the cost of electricity per kilowatt-hour, which can be determined for an area by contacting the local utility company; and
• time: the amount of time the heater is in use.
  

For example, a 1,500-watt space heater running for 10 hours at a rate of $0.10 per kilowatt-hour will cost $1.50. Using the formula:

Kilowatts x Rate x Time = Cost,

the usage can be figured as:

(1,500w ÷ 1,000) x $0.10 kWh x 10 hours = $1.50.

Space Heater Safety

Since space heaters can generate extreme temperatures at the surface, they have the potential to be dangerousand even cause injury. Although they are safe when operated correctly, it is estimated that 25,000 residential fires and 300 deaths are associated with the use of space heaters every year. When using a portable space heater, following these safety precautions, as well as any guidelines recommended by the manufacturer of the unit, can lessen the risk of accident or injury.

• Use only the type of fuel or energy intended for use with the specific device. The use of gasoline in a kerosene heater, for example, would be very dangerous.
• Never attempt to repair or replace parts in a heater yourself. This should always be handled by a qualified service center, since the results of repairing a malfunctioning unit could be dangerous.
• Use of extension cords for the power supply should be avoided. A cord marked 14 or 12 AWG can be used if absolutely necessary.
• Do not use space heaters in wet or moist areas, such as in a bathroom.
• Always keep heaters level and on the floor. If a heater has been placed on furniture and it falls off, or if a table it has been placed on collapses, the damage to the unit could result in a fire or shock hazard. Some units contain a tip-over switch which automatically shuts the power off if the unit is knocked over, but even these should be situated in such a way that they will not be at risk of falling over.
• If the surface of the unit has a high operating temperature, there should be a guard around the heating element to keep people, pets and combustibles a safe distance away from it.
• The unit should have an indicator light to signal when it is plugged in or turned on.
• Be sure to install the correct size unit for the space to be heated. Too large or small of a unit may actually decrease energy efficiency, or could cause pollutants.

Other Factors to Consider

When considering the use of a space heater, especially for the purpose of improved energy efficiency, there are several final factors to consider. Space heaters will only impact energy efficiency in a positive way if they allow for the home's main thermostats to be turned down.If a space heater is used simply in addition to central heat without lowering the central thermostat, it will only add to energy bills.

Here are some other things to take into consideration when deciding whether a space heater will be right for a given situation, and which type of space heater will work best.

• What area of the building will the heater be used in? Be sure to select an appropriate unit for the area, and carefully consider whether this area will really benefit from use of a portable heater to begin with. For example, heating a room thatis generally too cold but not often used anyway would simply suck energy without much return on savings.
• Space heaters that include a thermostat are more efficient than models that do not.
• If the unit doesn't have a thermostat, utilize the different settings onit for maximum efficiency. Once a heater has adequately heated a room at full power, turn the setting lower to maintain current levels, rather than adding more heat toan already warmed room.
• Select a heater with appropriate safety features for the application. For example, a heater that achieves extremely hot surface temperatures may not be a good choice in an area where small children are present.
• The surface temperature of the heater can also be an issue in areas where combustibles might be found in close proximity to the unit.
• Some units that use a fan can be noisy, which may be an issue in certain circumstances, and should be taken into account during the selection process.

Space heaters can be effective energy-savers under the right circumstances, and different types of units will perform better in different situations. Knowing a bit about acceptable applications, as well as the properties of different designs, can be helpful in deciding if the use of a space heater will be a good choice for a home.

Inspect Before You Sell

Sellers' Pre-Listing Inspections

Eventually, a buyer is going to conduct an inspection. You may as well know what they are going to find by getting there first.

Having an inspection performed ahead of time helps in many other ways, such as:

• It allows you to see your home through the eyes of a critical and neutral third party.
• It alerts you to immediate safety issues before agents and visitors tour your home.
• It may alert you to items of immediate concern, such as radon gas or active termite infestation.
• It permits you to make repairs ahead of time so that ...
• Defects won't become negotiating stumbling blocks later.
• There is no delay in obtaining the Use and Occupancy Permit.
• You have the time to get reasonably priced contractors or make the repairs yourself, if qualified.
• It helps you to price your home realistically.
• It may relieve prospects' concerns and suspicions.
• It may encourage the buyer to waive his inspection contingency.
• It reduces your liability by adding professional supporting documentation to your disclosure statement.
  

Never hire an inspector who is not a member of InterNACHI, which provides the most trusted and rigorous training for inspectors in the industry.

Copies of the inspection report, along with receipts for any repairs, should be made available to potential buyers.