In modern construction and renovation, there are numerous different types of construction sealants and each possesses its own specific strengths and weaknesses. With the increasingly widespread use of different styles of cladding on modern buildings, construction sealants are used to provide air and weather seals while still accommodating building movement through thermal expansion, settlement, or any of the other stresses and movements that buildings are subject to following construction.
The 6 Most Common Construction Sealants
Probably the most common type of construction sealant used by contractors, polyurethane sealants are a good choice for several different applications. Able to adhere to most surfaces without requiring a large amount of preparation, it is a general use sealant that has high abrasion and shear resistance.
They do, however, tend to degrade in the presence of UV light so while they are cheap and quick to apply, they will need more repairs and patches over a shorter period of time if used externally.
Polysulphide sealants are best used in commercial construction that relies upon their resilience under cold and wet conditions. After being allowed to set polysulphide sealants that have been applied correctly will be water-resistant and impermeable.
When used in construction, the durability of the sealant makes up for its comparatively high cost with a general lifespan of around 20-25 years. This makes it an excellent sealant for use on cladding such as rain screening.
Often used in residential situations, water-based latex sealants have a number of positives but an equal number of drawbacks. While easy to apply and cheap compared to most of the other types, latex is best suited to interior use due to their reasonably short service life.
Similar to latex sealants, the uses of acrylic sealants are limited by their one major drawback. Despite being reasonably cheap and being long-lasting in comparison to latex, acrylic has a limited movement capacity, rendering them unfit for use on joints that require a large range of movement or flexibility.
Acrylic sealants are most commonly applied to low-movement joints in construction as they have a long service life and don’t suffer from shrinkage.
Silicone sealants are widely used in construction owing to their large list of positive characteristics. UV resistant, flexibility, long service life, and temperature resistance make silicone sealant a great choice for a number of different construction projects including application to glass and bonding it to frames when used this way it provides structural support while also adding weather and air proofing qualities.
Silicone sealants are more expensive when compared to other sealants, and require a considerable amount of time to cure and set fully. However, the final product and durability of that product make it worth the wait and cost.
Butyl is a synthetic rubber sealant that adheres to most substrates. Highly resistant to weathering and reasonably priced for their longevity, butyl sealants have a low movement accommodation that coupled with their difficult application, makes them more of a specific use construction sealant.
Commonly used in curtain wall cladding systems where their ability to adhere to rubber and maintain weatherproofing qualities over a long period makes them an exceptional choice.
Making sure that the correct sealant is used for the correct job and that any application is done correctly and repaired promptly when needed will extend the lifespan of the building considerably and help prevent a number of common issues that older buildings face.