Interior:

	Around window and door frames.
	Between the sill plate and foundation.
	Along the sole plate of exterior walls.
	Around faucets, pipes, wiring, outlets, or vents in exterior walls.
	Around ceiling fixtures.
	Around water pipes, drains, bathtubs and other plumbing fixtures.
	Joints between wallboard or paneling and the floor or ceiling, on exterior walls.
	Around the frame of an attic door or entry.

Exterior:

	Around window and door frames.
	Between two different siding materials.
	The joint between foundation and siding.
	Corners and angles where siding materials meet.
	Around skylights, vents and chimney flashing in the roof.
	Around faucets, pipes, wiring, outlets, or vents in exterior walls.

The purpose of caulking is to seal any crack in the shell of your home. This is also true of divisions between heated (or cooled) and unheated spaces, such as an attic.

Types of Caulking Compounds

1. Oil or resin based, sometimes called regular or contractor's caulk -- exterior use only.

   This is an inexpensive, low durability caulk. It has largely been replaced by the better quality caulking compounds.

   Advantages:

   	low cost;
   	good adhesion to many surfaces;
   	shrinkage is moderate.

   Disadvantages:

   	low durability, 1 to 4 years;
   	poor adhesion to porous surfaces, like masonry;
   	tends to crack when dry;
   	must be cleaned up with mineral spirits;
   	should be painted;
   	some are toxic, check label;
   	limited temperature range.

2. Latex -- exterior or interior use.

   Advantages:

   	low to moderate cost;
   	good adhesion to most surfaces;
   	shrinkage is low;
   	will not crack or crumble;
   	cleans up with water;
   	can be painted;
   	non-toxic.

   Disadvantages:

   	varied durability, 2 to 10 years
   	will not adhere to metal
   	little flexibility when cured
   	needs to be painted when used on exteriors.

   Acrylic latex caulking compounds are common. These compounds tend to be more durable but more expensive than other latex caulking compounds. Some latex caulking compounds also contain silicone for increased durability, better adhesion to building materials and increased flexibility.

3. Butyl rubber -- exterior use only

   Advantages:

   	excellent adhesion to most materials;
   	good durability, 10 or more years;
   	will not become brittle, and has good resiliency;
   	can be painted after it has cured, usually one week.

   Disadvantages:

   	moderate to high cost;
   	variable shrinkage; may require two applications;
   	does not adhere well to painted surfaces;
   	toxic; follow label precautions.

4. Silicones -- available for interior or exterior use, check label.

   Advantages:

   	excellent adhesion to most materials;
   	very little shrinkage;
   	high flexibility and resiliency after curing;
   	can be cleaned with dry cloth if done immediately, otherwise use mineral spirits;
   	available in clear formula.

   Disadvantages:

   	high cost;
   	may not adhere well to painted surfaces;
   	many silicones cannot be painted;
   	can be toxic, follow label precautions;
   	may be flammable.

5. Urethanes -- interior or exterior use.

   Advantages:

   	expands when curing;
   	good for larger cracks;
   	available in easy-to-use aerosol cans;
   	excellent adhesion to most materials;
   	flexible;
   	can be applied at variable temperatures, check label.

   Disadvantages:

   	high cost;
   	must be painted to protect from ultraviolet radiation.