As a home inspector I can tell you the number one problem I see every day while inspecting homes here in Indiana is moisture intrusion. Too much moisture in a home can lead to wood rot, structural damage, mold, mildew, and other biological growth. This in turn can lead to a variety of health effects ranging from various allergies, asthma attacks and hypersensitivity pneumonitits, for example. Too much moisture in or around your home can also make for conditions which are conducive to termites and other insect activity.
Methods to control moisture really should start by builders building an energy efficient home with proper air-sealing, proper use of vapor barriers and vapor diffusion strategies. The entire building envelope, from the foundation to the roof, should be designed to not only prevent moisture entry, but also to allow any moisture which does enter, a means to escape. Unfortunately, all too often home inspectors find that builders just do not take the time to perform these necessary steps, nor do they take the time to educate home buyers about the importance of keeping moisture away from your home. The following tips are designed to help educate home buyers on how to discourage Indiana's number one enemy to your home......water.
The ground around your home's foundation should be graded to slope down and away from the house at a minimum rate of 6 inches for the first 10 feet to drain water away from the house. In some areas, there may not be enough room outside the dwelling to provide proper grading. In these cases, it is often recommended that an interior drain tile and sump pump be installed if you have a crawlspace or basement. For a slab foundation, a French drain can be installed around the perimeter of the home. Yes, slab foundations are also susceptible to moisture damage. Remember concrete is porous and acts like a sponge when it comes to water. Slowly absorbing the water and slowly deteriorating the concrete.
Gutters play a very important role in helping to shed rain water away from your home. Gutters filled with leaves and clogged with debris can lead to a variety of moisture issues with your home. If your gutters are always filled with debris, rain water will eventually back up into your roof decking and cause rot along the entire perimeter of your roof. Clogged gutters also spill over, dropping a waterfall inches from your foundation and will eventually erode the soil, causing flat to negative grading around your home. The best solution is to keep your gutters clean of any debris. Best of all, it doesn't cost a penny, just a little bit of time and effort. Make sure to check and clean your gutters at least twice a year. Late spring and fall are the best times to check for debris in your gutters.
Water from downspouts should be directed away from the house, discharging 4-6 feet from the foundation. Installing downspout extensions is a quick and inexpensive cure for a great deal of moisture problems. Downspout extensions can be purchased at any home improvement store for around $8.00-$15.00 a piece.
Vegetation such as trees, bushes etc. around your home can be beautiful and very appealing, however they can also be very damaging to the exterior of your home. Vegetation planted too close to your homes exterior will hold moisture next to your home. Remember your home needs to breathe. The exterior walls and the ground around your home need adequate time to dry out. If there is excessive vegetation around the exterior of the home, those walls and that ground never get a chance to dry and they will constantly be wet. This can be especially damaging to the foundation, wood siding and brick exteriors. It also makes for conditions which are conducive to termite and other insect activity. It is recommended to keep all bushes and trees away from your homes exterior. Never allow any vegetation to actually touch the home. Bushes and trees should be trimmed back a minimum of 3 feet away from the homes exterior walls and roof.
Mulch next to your home can also be very damaging. Personally I have never been able to understand the love for mulch. Having large amounts of wet, rotting wood next to your homes foundation and exterior walls is never a good idea. Not only does it hold moisture next to your home, it is also a haven for insects and mold growth. I recommend replacing wood mulch with rock. It may cost a little more upfront, but it will actually wind up saving you money in the long run because you never have to replace it every year like you have to for mulch, plus it offers the same protection for your plants and shrubs as mulch does without the damaging effects on your home.
If your home has a crawlspace, it is imperative to install a proper vapor barrier (also called Visqueen) over the entire crawlspace floor, overlapping the edges by at least 12 inches and tape all seams. A vapor barrier is essential to help prevent moisture from the ground from "wicking" up into your floor joists, sill plate and subflooring. Your crawlspace should also have proper ventilation. Some people unknowingly close off all of the vents to their crawlspace thinking that it will save them money on their utility bill. While it may save you a few dollars for a few months, it is never recommended to close off or block all of your crawlspace vents for the entire winter season. These vents are installed for a specific reason and that is to provide a proper cross flow of air through the area. The very same applies for your attic. Your home needs to breathe. If you close off your vents for the entire 4 to 5 months of winter we have every year, that few dollars you might save on utilities during that time will be nothing compared to the hundreds, even thousands of dollars you will wind up spending on mold remediation in your crawlspace or attic. One possibility to look into is purchasing automatic crawlspace vents. These vents will open and close automatically based off of the exterior temperature. It is also very important to make sure that any piping or ductwork in the crawlspace is professionally insulated to prevent freezing.
If your home has a basement, install a dehumidifier to keep humidity levels below 60%. If you need to, place two dehumidifiers down there to help control moisture. Humidity levels above 60% for a prolonged period of time in your basement can and will cause structural damage. Wood floor joists, sill plates, rim joists and subflooring can rot and warp over time just from high humidity. It is also recommended to Drylok your basement walls for added protection from exterior moisture entering your home. During the nice time of year, or whenever possible, open up your basement windows and allow the air to flow through the basement. This will also help to prevent that "basement smell" that occurs, especially in older homes.
Ensure that the interior of the home is also properly ventilated. High humidity indoors can lead to problems with mold, dust mites, and other biological pollutants. Using exhaust fans in the bathrooms and kitchen can remove much of the moisture that builds up from everyday activities and help to keep humidity inside the home below 50%. There are exhaust fans on the market that produce little noise, an important consideration for some people. Another benefit to using kitchen and bathroom exhaust fans regularly is that they also exhaust odors and pollutants from these rooms. These fans can be part of an active ventilation system for the entire house, and help to reduce humidity levels. Vent bathroom, kitchen, and clothes dryer/laundry room exhausts directly to the outside, NOT into an attic, crawlspace or other enclosed space. This will only defeat the purpose by moving the moisture to another area of the home. All exhaust fans must vent to the exterior of the home.
Taking these few yet very important steps will help to prevent unwanted surprises from not doing so. They will also help to maintain your homes resale value. Always remember that when you go to sell your home, another inspector will be in your home working for the buyers. You can save yourself a ton of money and a lot of heartache by following these few simple steps to keep moisture away from your home.