caulking products

Caulking materials are mainly used for small gaps and holes (say, less than 1/4" wide / 5 mm), but different locations, exposure to weather, different temperatures or different degrees of friction and pression may demand different caulking products.

Air Sealing Caulk quality

Caulking products have different prices and vary in their quality.

Look for an air sealing caulk that remains flexible for many years. Avoid the cheapest caulks. Silicone caulks and urethane based caulks are often the best caulking materials, but that's just a first approach to the issue...

Different types of caulking Products

There are several types of air sealing caulks:

- silicone caulks;
- urethane caulks;
- elastomeric latex sealant caulks;
- latex caulks;
- siliconized or silicone/latex caulks;
- acrylic caulks and...
- butyl rubber caulks.

Silicone and urethane caulks usually perform best overall, with elastomeric caulks coming next. Most silicone caulks aren't paintable, contrary to urethane and other caulking products.

A major disadvantage of silicone and urethane caulks is that they are difficult to apply. Latex caulks are much easier to apply and to clean...

But there are other criteria that should be considered when choosing a caulking product: high-temperature grade, fire-resistant grade, etc.

Butyl rubber caulks perform badly in most cases.

Caulks & foam caulks

Caulks and foams are often considered different caulking products. While air sealing caulks are used in small openings (less than 1/4 inch / 5 mm), foams are typically used in medium-sized ones.

But some new foams can be used as ordinary caulks, for small gaps... That's namely the case of some foam materials designed by Dow Chemical. See: Foam sealants

Selecting a Caulking Material

Pay attention to price, and to the caulk’s label, and to the elements mentioned above. Air sealing caulks vary in strength and properties, and low-cost caulks are often a bad option.

The label should tell you whether the caulking product is suitable for what you want to seal, and its type...

If the air sealing caulk is to be applied for penetrations bordered by different materials (wood, cement, glass, aluminum, steel…) the adherence of the caulk to the different materials is crucial. If the caulked joint is going to be visible, take into account the caulk's color or choose a caulk you can paint (most silicone caulks can’t).

Pay attention to the air sealing caulk grade: interior, exterior, high-temperature, fire-resistant, water-resistant, mildewcide (this last type of caulk is often advantageous, but should be avoided in dishwashers...).

When not to apply caulks

Do not apply common caulks in large penetrations and cracks (more than 1/4 inch / 5 mm wide). In these cases, air sealing foams are a better material.

Caulking materials can be applied where two surfaces meet (such as in window and door trims) but not on surfaces subject to movement (use weatherstripping products in the movable parts of windows and doors).

When sealing joints involving materials highly responsive to temperature variations (metal, plastic, glass…) gaskets are often more suitable than caulks. Only highly flexible caulks can respond properly to temperature variations.

Moisture

Some caulking products can also prevent moisture and water damage, inside or outside the home. Silicone caulks are ideal for bathrooms and kitchens, and around faucets, water pipes, drains, or in ceiling and plumbing fixtures...

Cartridges, caulking guns and quantities

For small jobs or special applications you may buy an aerosol or a squeeze tube…

For larger works, there are disposable air sealing caulk cartridges, fitting in half-barrel caulking guns (some pressurized cartridges do not require caulking guns).

You will probably need about a ½ cartridge per window/door or 4 cartridges for the foundation sill (that’s just indications to help you estimate your needs)...