A trip to your local home improvement store can be an overwhelming experience for the average person, especially if you’re trying to figure out which caulks and sealants to use for your exterior home improvement project. Unlike the interior, the exterior faces high UV exposure, extreme temperatures, and the requirement to stay 100% waterproof.
When you’re dealing with silicone caulks, you have a non-paintable surface, with poor UV performance. Although water-based and latex caulks have good paintability, they also have high shrinkage, reduced elasticity, and poor UV performance. Synthetic-rubber (polyurethane) sealants and tri-polymer sealants (silyl terminated polyether sealants) can do it all: paintable, excellent moisture sealing, no or low shrinkage, and very good UV resistance. Many are also pre-tinted in popular colors.
Sealant and caulk materials are heavily advertised and marketed with super flashy packaging, labels and all kinds of fancy logos. If you’re looking for a high-performance caulk or high-performance sealant, you can literally be confronted with hundreds of brands and companies that claim to have the best product for your needs. So what can you do, when you are bombarded with all kinds of choices?
Each brand of caulk generally has its own special and unique qualities. Although it is in your best interest to read all of the labels and also follow the company specifications, for the use of the caulk and sealant, the very thing you want to know may not be found on the labels of the containers at all! Many of the best products are architectural/commercial grade and not generally available to the public.
The sealant was originated through the needs for exterior finishing in the home building industry. Caulk was originally a term that was used to describe the sealant material used to build boats. Many companies and manufacturers these days are using caulk as an all-purpose word to describe paintable interior-grade products. Sealants by definition have at least /-25% elongation capability over a long-term period and are UV resistant. Advanced sealants are 100% solids and offer up to 100% elongation.
Most of the general public use caulk and sealant interchangeably to serve the same basic purpose, which is to fill the gaps between building materials and to shield cladding from air and water.
Although sealants and caulk work the same essential manner, they both also fail for the same fundamental reasons. There are three significant types of caulk failures that you will encounter. These are substrate, cohesive, and adhesive. The bond that is put between the substrate and the caulk can actually fail, making the caulk tear and break down. Caulked joint problems are also widespread and are usually due to the substrate not being adequately prepared or using the wrong product altogether.
You will also want to keep humidity, temperature, and moisture in mind when you are shopping for caulk or sealant. Water-based caulks not recommended for outdoor projects like siding replacement, because these products do not withstand the hot-to-cold and cold-to-hot weather changes, as well as other harsh weather situations. If you are living in an area that is below 50F during the time you need to apply sealant, then you’ll probably want to use a silicone sealant, instead of polyurethanes, because polyurethanes are very difficult to apply in chilly conditions.
To the delight of many, who prefer the do-it-yourself project, certain caulks and sealants can be color-matched to siding and windows. The beauty of these products is that they can be color-matched while they are still in the product tube. Any good home building products store will be able to help you color-match your caulk and sealant to your desired color. Once the caulk has cured, then it will precisely match the color you were seeking to acquire.
So, before you choose a particular kind of caulking, you want to really think about how you will be using it and for what purpose. You will also want to consider the area or location you are going to apply the caulk or sealant. For exterior projects like siding installation, our experience proved that the ultimate option is OSI QUAD Max sealant for its maximum durability and best performance.
In summary, let’s review your options again:
1. Water-based caulks are the easiest to work with. They have a smooth, thin and consistent flow, and they are easy to apply with almost any tool. These products cure quickly, have very little odor, and the clean up is easy with water.
2. Silicone caulks, and sealants are suitable for interior or exterior areas, which will not be painted and are suitable for areas that will be exposed to frigid weather, certain metals, and glass. Silicone materials do not repair well (nothing wants to stick to cured silicone material, not even more silicone)
3. Synthetic rubber sealant is best used for areas with high movement and dissimilar materials. These materials can be painted and are designed for long-term exterior exposure. There is also less chance that the synthetic rubber bond will break during movement. Typical applications are roof tile repairs, roof moldings, and roof to wall sealing, window frame sealants, and doorsill sealant.
4. New Hybrid products are available that defy all classifications. Using these kinds of sealants can yield a lot of surprises, so be sure to read the instructions carefully. Some of these products tend to expand upon drying, so it is best to test them out in an inconspicuous location before actually using them on your project.
If you do not know where to begin, siding companies in Seattle, WA may assist you. They will explain your many alternatives in terms of material, design, function, and price. They are also aware of how temperature and weather conditions effect particular siding sealant kinds.