Small cracks, crevices, and holes in your home let in cold air in the winter and let the warm air from your heating system escape. You can stop heat loss and eliminate these drafts with caulking. With just a few materials and some time, you will feel a difference, waste less energy, and save money in your heating costs.
There are many types of caulking to choose from and you should consider durability, flexibility, and whether caulk can be painted. Caulks are typically packaged in 10-oz tubes for standard caulking guns and the approximate coverage is 400’ at 1/4” bead, 200’ at 3/8” bead, and 100’ at 1/2” bead. Other size packaging is available- 1-qt builder’s tubes, 5-oz squeeze tubes, and rope caulk. It’s important to read product labels and manufacturer literature. And be sure to ask our associates for their recommendation. To help get you started, here is a list of common caulks and their characteristics.
- Oil-Base Painter’s Caulk (1-2 yr. life) – Not very elastic. Dries out easily. Paintable after curing. Lowest cost.
- Latex (3-10 yr. life) – Use mostly indoors. Goes on easily. Low elasticity. Sticks to porous surfaces only. Easy water cleanup. Low in cost. Paintable.
- Butyl Rubber (3-10 yr. life) – High elasticity. Sticks to most surfaces. High moisture resistance. Flexible when cured. Most difficult to work with as it is very sticky.
- Acrylic Latex (10 yr. life) – Good elasticity. Sticks to most surfaces. Reasonable moisture resistance. Paintable. Good for around doors and windows. May not be used below freezing.
- Silicon-Latex Blend (20+ yr. life) – Good elasticity. Excellent weathering ability. Medium shrinkage. Adheres to most surfaces. Some cannot be painted. May not be used below freezing.
- Silicone (20-50 yr. life) – Excellent elasticity. Sticks very well. Excellent moisture resistance. Needs solvent to clean. Strong odor possible while curing. Low shrinkage. Generally not paintable, but available in many colors. May not be used below freezing. May be applied to wood, asphalt or metal, but not vinyl or masonry.
- Urethane (20-50 yr. life) – Excellent elasticity and adhesion. Excellent moisture resistance. Easy cleanup. Strong odor possible while curing. Low shrinkage. May not be used below freezing. May be applied to wood, brick, asphalt, metal, vinyl or concrete.
- Elastomeric Copolymers (50+ yr. life) – Excellent elasticity and adhesion. Will stick to damp surfaces. Can be applied below freezing. Cleanup with lacquer thinner. May be applied to wood, brick, asphalt, metal, vinyl or concrete.
- Polyurethane Foam Sealant (in aerosol can) – A specialized expanding foam product useful for filling large gaps. Expanding foam may be tricky to apply because of the amount of expansion but has excellent sealing and insulation qualities.
- Most caulks should not be used on cracks larger than 3/8” or more than 1/2” deep. Fill the large cracks with flexible foam backer rod.
Caulking should be applied to any gap where air, moisture, or insects may penetrate the structure. Some common areas include:
- Joints between foundation and siding
- Joints between roof overhang and house
- Joints between window/door and siding
- At any penetrations into the house (telephone wires, TV cable, electrical conduit, gas and water pipes)
- Dryer, bathroom, and kitchen vents
- Joints between the siding and the chimney
As a rule, surfaces must be clean and dry in order for caulking to stick. Loose material should be brushed away, and dirt, grease or oil should be removed with a detergent solution. Do not apply in cold weather, except as recommended by the manufacturer.
To use a caulking gun, first pull the plunger all the way back and insert the caulking tube (see image).
Turn the plunger so the notches engage the trigger of the gun, then push the plunger snugly against the heel of the tube. Cut the nozzle tip with the utility knife and make a hole the size of the bead you want. Puncture the seal at the top of the tube with a 16d nail.
To apply caulking, squeeze the trigger and push-don’t pull-the gun along the gap (see image). Pushing the gun drives caulking down into the gap and gives you better adhesion.
To tool the joint, first wet your finger with soapy water (if the caulking is formulated for soap-and-water cleanup) or a dab of automotive hand cleaner (if the caulking is formulated for solvent cleanup). Run your finger along the joint, smoothing it and pressing the caulking into the joint. Wipe away excess with a rag.