Tips for selecting the right caulk for your next repair or do it yourself project.
Most do it yourselfers couldn’t live without caulk. Whether it’s used to conceal a bad miter joint, or close up a draft, caulk has become indispensible when working with many materials. It can reduce your heating and cooling bills as well as complete your bathroom tub and kitchen sink. There are many different types of caulk at your local hardware store, but hopefully these tips will help you select the right kind of caulk for all the different jobs in your home.
What is Caulk used for?
Caulk is a flexible material that is used to fill in gaps, cracks, and breaks in various surfaces. It is used to prevent heat loss around windows and doors, water leakage around toilets, bathtubs, cracks in your driveway and foundation. Sometimes referred to as sealant, caulk used to only be available in polyurethane and silicone forms. However, there are now a variety of different types of caulk specifically designed for a number of different home repair jobs.
Choosing Caulking for Your Project
When it comes time to choosing a caulk for a particular project you should consider the parameters of your job. These items will help you to decide what type of caulk to choose:
Indoor or Outdoor: Some caulks are designed for outdoor use, while others work better inside the home. Outdoor caulking can be used indoors, but it may cost much more than a comparable interior caulk.
Temperature: Consider the temperature in the place where you are going to put the caulk. Some types of caulk can withstand extreme temperatures while other types cannot.
Moisture: Some caulks are formulated to be installed in high moisture areas. An inappropriate caulk will lose adhesion and durability.
Application: Some types of caulk are much easier to apply than others. Consider your level of caulking expertise before you run out and purchase a hard-to-apply caulk.
Safety: Some special projects require specialized caulk. Food-safe caulks may be required if a material comes in contact with food in the kitchen; aquariums need special caulk that will not leach chemicals into the water.
Types of Caulk
There are many different kinds of caulk on the market and it is easy to get overwhelmed when trying to make a decision. This guide will help you to choose the right caulk for your project.
Silicone is one of the most common types of caulking and the one people are most familiar with. It is usually clear in color and has a rubbery, flexible texture when dry. Because of its durability and effectiveness on a wide variety of surfaces, silicone continues to be a popular choice. It is especially useful on non-porous surfaces, including metal and plastic. It stays flexible after it is dry and silicone caulk rarely breaks or cracks due to extreme temperatures or rapid temperature changes. This makes it perfect for filling gaps around windows and doors.
Silicone can be difficult to apply and has a strange odor, making this the primary choice for exterior caulking jobs. Additionally, silicone caulk needs to be cleaned up using a special solvent, which can become quite messy.
Latex caulk is becoming an increasingly popular option for many homeowners. Because of its durability, latex caulk can last for up to 20 years and it can also be painted over making it a good selection for trim and windows. Latex caulk doesn’t stand up to temperature changes and should not be used outside in cold regions. It performs fairly well for wood siding and filling small cracks in door frames and window frames. It also has a tendency to dry out over time and may crack.
This type of caulk is a mixture of acrylic, latex, and silicone caulks. It is easier to apply than regular silicone caulk but has a similar durability. Some types of blended caulking can be painted as well. This type of caulk is good for both indoor and outdoor uses, including wood siding, cracks in brick and stone, and for weatherproofing windows and doors.
Kitchen and Bath Caulk
Kitchen and bath caulk is designed for use in areas that have high moisture content. It can stand up to mold and mildew growth and is excellent for sealing bathtubs, shower stalls, toilets, and sinks. It is available in a variety of colors to match your fixtures or tile. Typically this type of caulk cannot be painted over, and if it could, the paint would peel off due to the moisture on the surface.
Butyl Rubber Caulk
Butyl rubber caulk is another popular caulk. It is excellent for use in gaps and cracks that are up to ¼" wide, such as gaps on windowsills and between doors and door frames, or between masonry and siding. Butyl caulk is strong and durable and can last up to ten years when applied correctly. It is also comes in a range of colors or it can be tinted to matching existing paint or siding. Some butyl rubber caulks can also be used to fill cracks in stone, brick, and concrete.
This type of caulk is designed for use in repair projects involving chimney repairs, flashing and pipe sealing, and outdoor vent sealing. Similar to a soft tar, oil-based asphalt caulk hardens very quickly and provides durable sealing for up to 4 years. For this reason it needs to be replaced or added to every few years.
Caulking cord is designed to be used as a temporary way of sealing off small gaps, such as those found around air conditioning units, windows and doors. Caulking cord comes on a roll and is then cut to size and placed in position. It can last anywhere between one and two years.
Backer rod it used to fill large gaps between two surfaces before caulking. How many times have you tried to fill a large gap only to watch half a tube of fall down a hole? Backer rod comes in several diameters and is made of a foam material, typically closed cell, but can also be open cell. It can be forced into a gap with a putty knife and caulked over. It is useful when sealing large gaps around windows, between siding and chimneys, or concrete expansion joints.
Most manufacturers specify a shelf life of 1-year from date of manufacturer for silicone caulk in unopened tubes. Silicone can last longer than a year, but it should be tested to determine if it will cure properly. Silicone does not air dry; it has a curing agent in the caulk. If a sample placed on a non-porous surface does not cure to a rubbery consistency in 24 hours don't use it. It will be very difficult to clean up after the fact.
Hopefully this will help to narrow down your choices when you select a caulk for your next do it yourself project.