How to know what sort of sealant to buy?
Posted on 23 March, 2022
Silicone sealant is a wide term that is commonly used in DIY. Initially, most people searching for a sealant would go to their local store and pick one in the right colour or the cheapest. However, this would be a mistake as there are different sealants for different purposes. There is a range of different varieties that all have varying elasticity, durability, and resistance.
What do you use silicone sealants for?
Sealants can be used for a range of tasks and hence the need for specific ones for certain jobs. Often sealants are used for:
- Sealing gaps around showers, windows and baths
- Repairing mirrors or glass to tiled surfaces
- Sealing gutters and downpipes
- Fixing rubber trim on cars
- Making reusable flexible moulds
Silicone sealants are utilized in a wide array of building applications due to their performance strength and characteristics that make them exceptionally useful such as UV resistance, higher movement capability, longevity, temperature resistance and malleability over time. Furthermore, they are waterproof and weather-resistant as well as working well against certain bacteria.
What types of sealants are there?
Acrylic
These are UV stable which makes them appropriate for exterior areas such as the outside of houses. They are also resistant to shrinkage. Acrylics can be challenging to fit and do not experience significant movement.
Butyl
Sticks excellently to a range of substrates but it can be slightly trickier to apply due to their stringier consistency. They have weak resistance to abrasion and can find it difficult to accommodate movements that introduce shearing forces. They are unsuitable for more demanding building projects or large-scale construction.
Water-based latex
Water-based latex is a popular choice for domestic settings due ease of application and its ability to cling to many substrates. Water-based latex can be painted on and are often a popular choice when there are gaps. Unfortunately, latex is can be susceptible to shrinkage and this may lead to the substrate causing gaps and water penetrating which can lead to structural damage.
Polysulfide
Excellent flexibility at all times and even at low temperatures. This means there is no UV degradation or little shrinkage. This makes the sealant suitable for underwater applications. Polysulfides are more expensive than other sealants and are likely to have greater levels of volatile organic compounds (VOCs). That being said the lifespan is 10 to 20 years which means it would be money well spent.
Silicone
Silicone is well known for its tremendous thermal resistance as well as excellent dynamic movement capability and good adhesion. Some issues include the fact that they collect dirt quite easily and can be vandalised. Additionally, for some substrates (stone, for example), staining might be a problem.
Silicone can also be used externally due to its weatherproofing and air sealing properties which makes them good for structural use. Silicones are normally the most expensive but quality silicones have exceptional durability characteristics.
Polyisobutylene
These sealants have remarkably similar properties to natural rubber. However, they are improved due to having better durability, high resistance to chemical attack, and have low permeability. These are usually used as the leading seal for insulating glazing units. They are able to resist the transmission of gases and vapour.
Polyurethane
Polyurethane works well on a range of surfaces and can adhere to them without much preparation. This makes them extremely popular for professionals such as contractors. They have strong resilience to abrasion as well as having movement capability and strong adhesion.
A type of sealant is not necessarily worse or better than others but some simply perform better in certain environments due to their properties.
Here at BC Profiles, we are eager to help and provide you with any problems or issues you may face. Therefore, whether you are a professional working on a huge industrial project or a homeowner who is undertaking some DIY or refurbishments our highly skilled team is on hand. If you have any questions please do not hesitate to get in touch and we will be able to help. Additionally, browse our store for any and all of your sealant needs as we have a huge range of products from domestic and global providers such as Soudal.