Renovation & Design

Interior humidity could be cause of window-caulk mildew

Jean Levac / Ottawa Citizen files

Mould and mildew on window caulking could be the result of high humidity levels.

Question: Year after year, mildew develops along the caulking/sealant around my windows. In past years, my husband has regularly used bleach and much elbow grease to clean it. We don’t mind the normal amount of work a house takes, but this is ridiculous, not to mention probably harmful to our health — both the guck and the bleach solution!

The last two years have shown much growth of the mildew. We were almost prepared to replace all our windows until the inspector who did our energy audit said the windows were quite fine and only a few were leaking to a minor extent.

Do you have any suggestions of how to clean off the guck safely and in a non-toxic way, effectively and for more than just a few months? I hate the thought of removing all my windows and having them in a landfill site when they’re still fairly energy efficient.

— Kale

Answer: Based on your description, the problem does not sound like a window problem, but rather high humidity levels in your home coming from day-to-day activities such as boiling water, bathing, the dishwasher, etc.

To reduce condensation in your home, make sure you use fans in the kitchen and bathroom, as well as a dehumidifier when necessary. It may be worth your while to call a professional to access moisture levels in your home and to verify that you have proper ventilation and insulation in your roof, crawl space and basement.

Making the proper changes in your home, such as upgrading your furnace may be advised. If you do decide to make changes, check to see if the government is offering any homeowner energy grants in your area.

In terms of cleaning the windows, you can combine vinegar with 10 to 15 drops of tea tree oil. This will give you a great clean, but is not a long-term solution. Tea tree oil can be found in pharmacies at grocery and health-food stores. Ask your local pharmacist.

Question: I become very frustrated in the winter when I wash my car. After it sits for awhile in freezing temperatures, the doors are stuck and impossible to open. Any advice?

— Nick

Answer: After the car is clean and dry, spray non-stick cooking spray on the inside frame and the inside door. Be careful not to spray the coating on your upholstery.

Note: Every user assumes all risks of injury or damage resulting from the implementation of any suggestions in this column. Test all products on an inconspicuous area first.

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