Preventing Water Damage in your Home

Originally published at NACHI.ORG

Water may be essential to life, but, as a destructive force, water can diminish the value of your home or building. Homes as well as commercial buildings can suffer water damage that results in increased maintenance costs, a decrease in the value of the property, lowered productivity, and potential liability associated with a decline in indoor air quality. The best way to protect against this potential loss is to ensure that the building components which enclose the structure, known as the building envelope, are water-resistant. Also, you will want to ensure that manufacturing processes, if present, do not allow excess water to accumulate. Finally, make sure that the plumbing and ventilation systems, which can be quite complicated in buildings, operate efficiently and are well-maintained. This article provides some basic steps for identifying and eliminating potentially damaging excess moisture.

Identify and Repair All Leaks and Cracks

The following are common building-related sources of water intrusion:

• windows and doors: Check for leaks around your windows, storefront systems and doors.
• roof: Improper drainage systems and roof sloping reduce roof life and become a primary source of moisture intrusion. Leaks are also common around vents for exhaust or plumbing, rooftop air-conditioning units, or other specialized equipment.
• foundation and exterior walls: Seal any cracks and holes in exterior walls, joints and foundations. These often develop as a naturally occurring byproduct of differential soil settlement.
• plumbing: Check for leaking plumbing fixtures, dripping pipes (including fire sprinkler systems), clogged drains (both interior and exterior), defective water drainage systems and damaged manufacturing equipment.
• ventilation, heating and air conditioning (HVAC) systems: Numerous types, some very sophisticated, are a crucial component to maintaining a healthy, comfortable work environment. They are comprised of a number of components (including chilled water piping and condensation drains) that can directly contribute to excessive moisture in the work environment. In addition, in humid climates, one of the functions of the system is to reduce the ambient air moisture level (relative humidity) throughout the building. An improperly operating HVAC system will not perform this function.

Prevent Water Intrusion Through Good Inspection and Maintenance Programs

Hire a qualified InterNACHI inspector to perform an inspection of the following elements of your building to ensure that they remain in good condition:

• flashings and sealants: Flashing, which is typically a thin metal strip found around doors, windows and roofs, are designed to prevent water intrusion in spaces where two building materials come together. Sealants and caulking are specifically applied to prevent moisture intrusion at building joints. Both must be maintained and in good condition.
• vents: All vents should have appropriate hoods, exhaust to the exterior, and be in good working order.
• Review the use of manufacturing equipment that may include water for processing or cooling. Ensure wastewater drains adequately away, with no spillage. Check for condensation around hot or cold materials or heat-transfer equipment.
• HVAC systems are much more complicated in commercial buildings. Check for leakage in supply and return water lines, pumps, air handlers and other components. Drain lines should be clean and clear of obstructions. Ductwork should be insulated to prevent condensation on exterior surfaces.
• humidity: Except in specialized facilities, the relative humidity in your building should be between 30% and 50%. Condensation on windows, wet stains on walls and ceilings, and musty smells are signs that relative humidity may be high. If you are concerned about the humidity level in your building, consult with a mechanical engineer, contractor or air-conditioning repair company to determine if your HVAC system is properly sized and in good working order. A mechanical engineer should be consulted when renovations to interior spaces take place.
• moist areas: Regularly clean off, then dry all surfaces where moisture frequently collects.
• expansion joints: Expansion joints are materials between bricks, pipes and other building materials that absorb movement. If expansion joints are not in good condition, water intrusion can occur.

Protection From Water Damage

• interior finish materials: Replace drywall, plaster, carpet and stained or water-damaged ceiling tiles. These are not only good evidence of a moisture intrusion problem, but can lead to deterioration of the work environment, if they remain over time.
• exterior walls: Exterior walls are generally comprised of a number of materials combined into a wall assembly. When properly designed and constructed, the assembly is the first line of defense between water and the interior of your building. It is essential that they be maintained properly (including regular refinishing and/or resealing with the correct materials).
• storage areas: Storage areas should be kept clean.  Allow air to circulate to prevent potential moisture accumulation.

Act Quickly if  Water Intrusion Occurs

Label shut-off valves so that the water supply can be easily closed in the event of a plumbing leak. If water intrusion does occur, you can minimize the damage by addressing the problem quickly and thoroughly. Immediately remove standing water and all moist materials, and consult with a building professional. Should your building become damaged by a catastrophic event, such as fire, flood or storm, take appropriate action to prevent further water damage, once it is safe to do so. This may include boarding up damaged windows, covering a damaged roof with plastic sheeting, and/or removing wet materials and supplies. Fast action on your part will help minimize the time and expense for repairs, resulting in a faster recovery.

We invite you to check out our last blog article about attic insulation.

Inspecting ICFs and Termites

by Nick Gromicko and Ethan Ward
Originally published at NACHI.ORG

Insulating concrete forms (ICFs) are rigid, plastic foam forms that hold foundation and structural concrete in place while it cures, and then stay in place afterward to provide insulation. ICFs provide some advantages over more traditional construction materials and methods, including improved durability, and protection from fire and natural disasters, as well as added energy efficiency.  However, a major problem associated with ICFs is termite infestation.  Because of this, some states where termite infestation is common have banned ICFs from underground use for basements and foundations.  Inspectors who examine foundations in regions where termites are a known problem can benefit from understanding the difficulties of identifying infestations in ICFs.  Consumers planning a new build will want to be aware of strategies for preventing such problems.

Termite Types

There are three main kinds of termites found in North America:  dampwood, drywood and subterranean.  Dampwood termites are found mostly in the Pacific Northwest and coastal British Columbia.  These pests attack decaying wood and can usually be controlled by removing their moisture source, unlike drywood termites, which do not require a significant moisture supply. 

Drywood termites are often found in the southernmost parts of the continent, including Hawaii and Mexico.  They can fly directly into buildings and begin colonies in dry wood.  The use of treated wood is generally effective for controlling infestations of this type.  Dampwood and drywood termites are not the biggest concerns in relation to ICFs.

Subterranean termites are the real worry with ICFs, and they cause the most damage to building structures.  These termites live in the soil in order to avoid being affected by extreme temperatures while maintaining access to essential moisture.  They attack any source of cellulose within foraging distance of their colony, such as dry wood.  In addition to wood, they feed on cardboard, paper and fiberboard that are in contact with or close to the ground.

The Formosan termite, which is a type of subterranean termite, is the most aggressive and destructive.  Although typically smaller than most other species, its colonies can cause damage faster than other termites due to the sheer numbers they travel in.

Damage to Structures

It may seem strange that termites could be a concern for structures that are, by definition, mostly concrete, since they would not seem to provide an obvious food source for the bugs.  The confusion often comes up because it is assumed that termites need direct access to their food in order to begin causing damage.  However, the resourceful subterranean termites have found ways to actually use ICFs to their advantage when looking for food.

When a source of food is not directly in contact with the soil, subterranean termites will build tunnels to get to it.  The tunnels, called shelter tubes, can go through cracks in concrete foundations and slabs, as well as through spaces around utility pipes. 

The problem with ICFs is that, while the EPS insulation on the outside does not provide the termites with a source of food, the termites can tunnel through it to their food sources virtually undetected.  In one of many reported cases, there were no outward signs of infestation.  Meanwhile, termites had tunneled inside the EPS all the way to the roof and were feasting.  By the time the wood components of the house had begun to show signs of infestation, significant damage had already been done.  The cover that EPS insulation on the outside of ICFs provides for termites, allowing them to tunnel toward food undetected, is the main concern in states that have restricted the use of ICFs.

Protecting ICFs from Termite Infestation

Solutions for protecting ICF structures from termites have been implemented successfully throughout the U.S., and it is not difficult to adapt or modify existing means of control to work compatibly with ICFs.  The following are some means for preventing and controlling termite problems that have been used successfully with ICFs.

Depending on the locality, some of these strategies may be required by code for ICFs that extend below ground.

• Waterproofing and barrier systems, such as Polyguard 650 XT, have been designed specifically for use with ICFs.  These membranes accomplish the dual purpose of waterproofing the foundation while simultaneously protecting it from termites.
• Chemical treatment of soils around foundations using a termiticide has proven helpful in controlling termites near traditional wood buildings, and is also helpful around structures using ICFs.  However, the use of these treatments is banned in some areas where chemical agents could seep through soils with high water-table levels, potentially resulting in groundwater and soil contamination.
• Metal shields with properly sealed joints attached over foundation walls force termites to try to build their tunnels on the outside of the shield, where the termites are more easily detected and can be dealt with accordingly.  This helps prevent the hidden tunneling that they can do through EPS insulation.
• Particle-size barriers made of granules of rock are also useful.  The rocks are small enough that, when compacted together, leave spaces between them that are too small for termites to get through.  These barriers can be used effectively under slabs, around plumbing, and around ICF foundations to create a physical barrier to termites.
• Steel wire mesh is also available for creating a physical barrier that can be installed with ICF foundations.  The most popular wire mesh is called Termimesh® and is constructed so that the holes in the mesh are too small for termites to fit through.  Proper installation of this mesh is critical for it to be effective, and it must be installed by a professional trained by the manufacturer.
• If termite problems have already occurred, there are various baits and traps designed to mitigate the infestation so that repairs can begin.  These are typically designed so that termites come in contact with a slow-acting chemical toxicant which they then spread throughout the rest of their colonies.

Termite problems with ICFs can, initially, seem confusing, since ICFs themselves are not a source of food for the bugs, but tunnels running undetected through the outer EPS insulation to food sources are a serious concern in some areas.  Understanding this problem and knowing how to prevent it can be helpful to InterNACHI inspectors who examine ICFs in regions that are susceptible to termite infestation.

We invite you to check out our last blog article about air sealing exhaust fans.