The prep for caulking and sealing small repairs like windows and doors is usually pretty minimal. The surface needs to be clean and dry and it is best if the temperature is at least 55. Rain should not be in the immediate forecast as the caulk needs to cure properly. Using the right material for the job, however, is critical. Price is not really an issue, as most of the caulking materials are inexpensive, but there are some ease-of-use issues. The water-based spray foam is probably the easiest for a novice to use around windows and doors and the clean up is pretty easy. Look for low or no-VOC products that carry the Greenguard label to maintain good indoor air quality.
Here is a chart from Consumers Reports that outlines several products and their best uses:
|Type of Caulk||Best Use(s)||Pros||Cons||Price|
|Acrylic tub and tile||To seal kitchen and bathroom fixtures.||Flexible; mildew resistant; cleans up with water.||Not paintable; not as durable as 100% silicone.||$4 and up per tube|
|Butyl rubber||To seal and fill around windows and skylights and around flashings and in gutters to seal dissimilar materials (glass, metal, plastic, wood, and concrete). More flexible (can stretch in multiple directions) than silicone. Good in areas that experience high temperature variations. Formulations with with asphalt are best for roofing repairs.||More flexible (can stretch in multiple directions) than silicone; can be painted after curing one week. Good in areas that experience high temperature variations. Formulations with asphalt are best for roofing repairs.||Does not adhere well to painted surfaces; shrinkage varies; might require two applications. Can be toxic; precautions must be taken and requires solvent cleanup.||$3.50 and up per tube|
|Concrete and mortar repair||To repair cracks in concrete and damaged masonry and mortar.||Can be shaped to fit before drying; remains flexible, cleans up with water, dries to color of concrete mortar or can be painted.||Not recommended for horizontal surfaces where water could accumulate.||$4.50 and up per tube|
|Latex||To seal gaps in exterior walls and plug holes and fill gaps in interior walls and woodwork before painting.||Inexpensive; takes paint well;, can be sanded; easy to work with; cleans up with water.||Will crack eventually where temperatures vary greatly (acrylic latex formulations are more durable); needs to be painted when used outdoors; won’t adhere to metal.||$1.50 and up per tube|
|Oil or resin-based||To seal gaps in exterior walls.||Inexpensive; will bond to most surfaces.||Cracks after a few years; much less durable than elastomeric (silicone, latex, or acrylic) caulks.||$1 and up per tube|
|100% silicone||To fill around pipes and vents and building structures made of nonporous materials and plumbing fixtures. Not as effective on wood or masonry.||Very durable and flexible; doesn’t crack.||Expensive; limited colors; can’t be painted or sanded, gives off strong odor when curing; solvent required for cleanup.||$4.50 and up per tube|
|Siliconized latex||Same uses as 100% silicone, except not on plumbing fixtures.||Very durable and flexible; rarely cracks, many colors available; cleans up with water; less expensive than 100% silicone.||Can’t be sanded.||$3.50 and up per tube|
|Spray foam (polyurethane-based)||To seal around window and door frames or to fill cracks and holes.||Expands more than latex and fills a greater area than caulking alone.||Expands after application, so it can warp door and window frames; can’t resist UV light; must be painted for exterior use; very difficult to clean up after use.||$5.40 and up per can (but one can fills as much space as many tubes of caulking)|
|Spray foam (water-based)||Around window and door frames or to fill cracks and holes.||Does not expand as much as polyurethane foam; can be shaped while wet; easy cleanup with water; will not cause windows or doors to bind.||Does not adhere as tightly to materials as urethane; takes longer to cure (up to 24 hours).||$5 and up per can (but one can can fill as much space as many tubes of caulking)|
Chart Courtesy of Consumer Reports.