Things You'll Need
Stick of incense
Polyurethane spray foam insulation kit
Paint or varnish (optional)
Gaps between the floor and the baseboard can cause cold drafts to enter your home, as well as air leaks that result in heat loss. Danny Parker, a research scientist with the Department of Energy, estimates that the homeowner could reduce energy consumption by between 3 and 18 percent by sealing household drafts. A good quality spray foam sealant or caulking compound will provide a durable seal for several years.
Identify air passages between the baseboard and the hardwood floor by holding a burning stick of incense close to the point where they meet. If the smoke dances, it means the air is moving and this could indicate the presence of a draft or air leak.
Clean thoroughly around the area where the source of the draft exists. Remove the remains of any previous repairs by scraping out old caulking, loose wood and debris. Vacuum the area to ensure that the space between the floor and the baseboard is dust-free and completely dry to avoid sealing in moisture.
Fill the gap with expandable spray foam using premixed, open-cell polyurethane sealant. The spray foam is generally sold in a DIY kit with two dispensing units and is ideal for use on irregular surfaces such as hardwood flooring. It expands during the curing process to fill the space and is suitable for use in areas without a high level of foot traffic.
Fill the gap completely with the sealant, using either the dispensing kit or a caulking gun. If the foam oozes outwards, press it in with a putty knife. After it cures, check to see if it has shrunk; if so, reapply it in a smooth rope to seal the remaining space completely.
Paint or varnish over the foam rubber to match the color of your hardwood floor or the baseboard. This will help to disguise the sealant. Reapply annually or as you notice the sealant disintegrating and becoming powdery.