How to Caulk – Caulking Tips
Caulking is a quick and easy way to keep the elements outside where they belong.
Caulking is a resilient material used to fill joins between different parts of a house to keep those joins air- and watertight.
Caulking compound is a mixture of pigment and natural or synthetic oils that make the compound elastic and resilient. It adheres to wood, metal, masonry and ceramic, keeping its elasticity so it can expand and contract with surrounding surfaces.
There are five different types of caulking compound — oil based, which will adhere to most surfaces; latex based, which can be cleaned up with water, is fast drying, and can be painted; butyl rubber, which is a long-lasting caulking used mostly for metal to masonry joints; polyvinyl acetate, which adheres to all surfaces; and silicone caulking, which is a long-lasting compound that adheres to any surface except paint.
Although available in a wide range of colors, the most common colors are white, gray and black. The compound can be purchased in bulk quart or gallon form or in disposable cartridge for use in a caulking gun.
For efficient application, caulking is usually applied with a gun which forces the compound out through a nozzle. The nozzle can be cut at various levels to control the width of the caulking bead you lay. If you purchase your compound in bulk, it can be loaded into a full-barrel gun for application. Caulking is placed into the barrel and a cap containing the nozzle is screwed into place. As the trigger of the gun is squeezed, a plunger in the barrel is activated, forcing the compound out through the nozzle.
Buying compound in bulk is efficient only when large areas of one color are to be caulked. Otherwise you need to clean the barrel of one color of caulking before you can refill the tube with another — a time-consuming and messy job. Therefore, most homeowners prefer to buy the compound in disposable cartridges. These cartridges are operated in a half-barrel gun in which the top half of the barrel is missing for easy insertion
of the cartridge. Changing colors simply means changing the cartridge.
To operate the gun, squeeze the trigger with a steady, uniform pressure and tilt the barrel at a 45° angle in the direction of the movement. The object is to lay down a neat, continuous convex bead of the compound on both sides of the join to be sealed.
Before you can start, however, any old caulking must be removed, otherwise the new caulking won’t adhere. Nor will caulking adhere to a greasy, damp or dirty surface. Clean the surface and rub it with a cloth soaked in solvent to ensure a clean base for adhesion.
Caulking is used to seal around door and window frames, where the chimney meets roof shingles, between steps, porches, patios and the main body of the house, around all roof flashing, at siding corners, to fill fine cracks in stucco, siding or woodwork or beneath windowsills.
Inside the house, caulking is mostly found around the edge of the bathtub where the tub meets the walls. But any small cracks in the bathtub area can be filled with caulking to prevent water seepage. Caulking can also be used as a gasket around taps where the faucet body meets the sink. This will help keep water out from under the taps, preventing possible corrosion of the metal. Caulking is also used to seal air leaks around windows.
If you need to fill large cracks, don’t proceed to fill up the hole with caulking. The large amount of caulking needed may have trouble drying. Instead, buy some oakum, a rope-like substance available in hardware and marine-supply stores. Fill the crack with the oakum to within 25mm (1in) of the surface, then apply the caulking Caulking can also be bought in dried-rope form, which is unwound from a roll and forced into cracks by hand.
Bows in a wall will prevent new baseboard molding from fitting flush to the wall. To remedy, fasten the baseboard and fill gaps with caulking before painting.