Ask Dave    |    About us    |    Members
Home    |    Articles    |    Plans    |    Custom Plans    |    Dictionary    |    Our eBooks    |    Newsletter    |    Member Photos

Remodeling 2: Moisture and Humidity Problems in the Home

Your home's worst enemies are dampness, high humidity and lack of ventilation. I live on the West coast of British Columbia, the banana belt of Canada, or so we boast. With the warmest winter climate in Canada comes the problem of moisture infiltrating our homes. Don't despair, however, for every home improvement problem has a solution. In this article, I'll discuss ways in which the average homeowner can attend to moisture and humidity problems in the home, without spending a fortune.

When it's time for an exterior paint job, take a close look at the caulking around the house. Places like the wood trim around windows and doors, on corner board joints where they form a 90 degree corner and around vents. Anywhere you notice a joint opening up, caulk it up.

Some good home improvement news is the types of caulking the industry has developed over the past few years. My choice is an acrylic latex caulking with silicon added for adhesion. These caulks are paintable and come in various colours as well as clear. Remember, they can be painted, and should be painted for added protection.

Caulking, for those not familiar with this operation, is applied with a gun, pushed into the joint and smoothed with your finger. Use a damp rag for clean up and keep your finger wet. Pick a warm day without chance of showers for 24 hours.

Now that you have secured the envelope of your house with caulking, let's go inside and see how many home improvement problems we can solve. Let's start with the kitchen and bathrooms, the highest humidity areas in the house. How many cooks in the household actually take the effort to turn the range hood fan on while cooking? I cannot emphasize enough the importance of turning that switch on when using the stove or oven. If you noticed a hole in the side of your house where the rain could run in, wouldn't you close it up? Moisture enters your kitchen, if you don't turn the fan on, where does it go? Look on the inside of the windows, that water's from moisture inside the home condensing on the cool window surface. It may be coming through the exterior envelope, through the windows or other places. We'll discuss these later, but most of it is probably coming from moisture created inside your home.

Do you have a good operating fan in the ceiling of each bathroom? Contrary to popular belief, the fan is not in there just to remove hubby's foul odours while sitting on the throne. Turn it on when taking a shower or bath and leave it on until the mirror clears. You can get timer switches that turn the fan off after a time.

In recent years they have developed de-humidifier switches that turn your bathroom fan on when it senses humidity. This is actually included as part of the Building Code in some jurisdictions for new construction.

If your fan is too noisy you can easily install a quieter one, there are many models to choose from.

I've replaced entire walls where there had been so much moisture in a shower room that the drywall literally turned to mush and the studs were black with mold. Those house owners weren't stupid. It's just that no one had warned them. After they saw the mushy drywall they insisted I install a bathroom fan, and rightly so.

Let's go down to the basement. Is your basement a storage area or is it finished? Do you have your concrete walls strapped and covered? Are there boxes of treasures stored down there that you haven't looked at for awhile? Are the sides of the boxes damp? Pay particular attention to those boxes placed tight up against the basement concrete wall or other outside walls.

Concrete is particularly bad for being cold and damp. Any moisture in the air will condense on it and collect on any thing else tight against concrete. The simple home improvement solution is not to pile your boxes tight to the outside walls. Leave about three inches of space for air to move around and dry that dampness out. The long term solution is to strap concrete walls with 2x4's, then apply insulation, vapour barrier and even drywall or panelling.

When storing boxes on a concrete floor put blocks of 2x4's or 2x6's under them. The idea is that air movement dissipates dampness.

If you have a crawl space, check it out periodically by looking for evidence of moisture or mold.

Is the basement floor dirt rather than concrete? You can cover the dirt with vapour barrier grade 6 mil poly. In new construction, crawl space floors are covered with poly then a skim coat of about 2" concrete is poured over it.

When the warmer weather comes, open up the crawl space vents. Your nose will usually warn you of mildew or mold growing in the crawl space or basement when you smell that 'musky' odour. I felt sorry for a young couple who were trying to sell their older house. The realtor called me to go and inspect the crawl space, being mainly concerned about no concrete footings to support a beam down there. Well, I stuck my head in the access, getting ready to crawl in for a closer inspection when the musty smell hit me.

I could see that there was only about 12" clearance below the floor joists to the damp mold covered dirt. I slowly backed out, wiped the cobwebs off my hat and promptly apologized that I didn't really want to crawl on my belly under their house to work on a missing concrete footing. I guess the look on my face was really a clearer indication of my feelings. They said they totally understood. You don't have to let your crawl space get that bad, of course. If you check it each Spring you can easily maintain it so it doesn't turn into a home improvement nightmare.

My son-in-law and daughter bought an old house that had been used as a rental house by his family for years. Well, the day came for him to venture down into the crawl space for an inspection. Poor Mario didn't know what to expect, but he was prepared for the worst. My daughter took a picture of him before he went down to his doom. He was wearing a tuque pulled down over his ears, a heavy plaid shirt duct taped to his wrists, old jeans duct taped to his steel toed work boots and carrying a shovel. He said he was ready for rats, spiders, cobwebs or anything else that lived down there. Luckily, he discovered a dry, rodent and pest free crawl space even though it had a dirt floor. This house was in the interior of BC where there's a drier climate than what I'm used to on the west coast.

One of the easiest home improvement problems to avoid, yet for some reason I see all the time, is topsoil overlapping the bottom row of siding on the house. There should be a minimum of six inches of concrete foundation wall showing below your siding or stucco. Dirt that is on wood or stucco will trap moisture and rot and if left long enough will get into the structure of the walls and rot those, too. I've seen this many times and repaired it many times.

I hope I've stressed the importance of air movement and the expulsion of moisture inside and outside of your home. Turn that fan on, let air get around your basement and crawl space and caulk up the exterior joints that need it.

One last home improvement tip. When buying an older house, pay that inspector his dues. He'll give you a report of what needs attention and your offer on the house can be based on this report.

< previous article next article >


(Ask Dave) (About Dave)

Sign up for our free monthly
newsletter and get
Free Woodworking Plans

Get free access to this article and two
others of your choice, just by entering
your email address below.

Receive our free Monthly newsletter which contains a
free set of woodworking plans each and every month.



Already a Member? Login here:



Forgot your username or password? Click here.
Become a Member.