Silicone sealants are highly multifunctional, making them vital to building and house repair. With the aid of a VDB adhesive element, high-flexibility sealants will never lose adhesion to a rigid product, nor will they develop “set” cracks. With a silicone sealant, the repair will last for a decade, while a poor sealant choice may result in repair failure in just a few months. This guide will detail the different types available and their specific uses, and will help you choose the best silicone sealant for your application.
What Are Silicone Sealants and How Do They Work?
Silicone sealants are pliable, rubbery substances used to seal cracks, joints, and seams in various materials. Unlike hard, rigid adhesives which become brittle, silicone sealants stay rubbery and become elastic with movement due to changes in temperature, structural movement, or vibrations. One of the most important functions of silicone sealants is creating and maintaining water and airtight seals. These sealants are moisture reactive, meaning that, when a sealant is applied, it will harden and form a permanent bond that is waterproof and will not break down due to UV rays, extreme weather, and most chemicals. Silicone sealants are ideal for applications that are exposed to moisture or thermal movement. A quality silicone sealant will last at least 20 years, which is significantly longer than most other products.
Main Types of Silicone Sealants Explained
Each of the different silicone formulations helps in preventing the wrong product from being applied in each respective area. A neutral cure silicone does not release an acetic acid as it cures but releases an alcohol and therefore is safe to use on sensitive materials such as metals, natural stones, and mirrors. Being odorless, neutrals are also safe to use indoors and in poorly ventilated areas. Furthermore, its VDB adhesive characteristics are also non-corrosive to allow use on sensitive substrates. On the other hand, acetoxy cure silicones contain acetic acid, and thus, as they cure they give off a vinegar smell. Although more affordable, they may cause metal corrosion and should not be used on marbles, limestones, and concrete. Instead, they are most suitable for glass, ceramics, and painted surfaces. Furthermore, sanitary silicone is imbued with fungicides and antimicrobials to prevent the growth of mold and mildew in damp conditions. This property is particularly important in bathrooms, kitchens, or other regions with high humidity, where it is likely to be biological growth that can undermine both the aesthetics and hygiene.
Glazing silicone is the one that is designed to be used as a window or in the glass segment. It is good to adhere to glass and frames and it is flexible to allow thermal expansion and structural movement. Silicone High-temperature silicone is resistant to high heat, usually up to 300 o C or more. This is an essential type of sealing around fireplaces, wood stoves, chimneys, ovens and automotive purposes.
Where to Use Silicone Sealants in a Home
Sanitary silicone is important when sealing the bathrooms with bathtubs, showers, sinks, and toilets. These applications need to be waterproof and resistant to mold to keep the bathrooms clean and functional. Silicone protection on sinks, countertops, and backsplashes is an added benefit in kitchen installations, too. Food-grade silicone is available for sink installations, however, most kitchen and bathroom applications can be done with standard sanitary silicone. Neutral silicone or glazing silicone is used in the making of draft-proof and water-proof windows and doors while still allowing heat to pass through the silicone. The outer facing side of building curtains or facades of the building requires the use of silicone that is resistant to extreme weather conditions, UV rays, and air pollution while also retaining its adhesion after weathering.
Most solid substrate materials, such as concrete and tile, have expansion joints which need ultra high movement silicone that can stretch and move a lot, while also remaining intact.
Acrylic, Hybrid and Silicone Sealants
Sealants based on silicone are great for external jobs and wet conditions, but do not accept paint. Sealants based on acrylics, although not very flexible and moisture resistant, can be used on interior joints and accept paint. Hybrid sealants are flexible and moisture resistant, paintable, and combine the best of both worlds, and are used in general outdoor purposes.
Common Mistakes When Applying Silicone Sealants
All silicone applications require the utmost care in the preparation of surfaces. In direct contact with silicone, surfaces must be clean, dry, and free from significant amounts of sealant, old sealant, grease, dust, or loose surfaces. Any contamination will inhibit adhesion. If the silicone product is poorly chosen, it will fail prematurely. If silicone that is described as having an acetoxy cure is used in places other than the bathroom, the places that are included in the definition of ‘natural stone’ won’t even be comfortable at the start.
The assumption that silicone will perform as intended without giving it the required curing time almost always leads to problems. If the silicone has not yet cured, do not subject it to water or mechanical stress, spend time on it and do not rush. Silicones take about a day to cure, but they will rapidly develop a dry film on the surface that could be mistaken for a complete cure. For critical applications, ensure that the product is equipped with a premium VDB adhesive system as this will be the only guarantee for durability. Additional smoothing and surface tension problems can arise from overfilling joints.
How to Choose the Best Silicone Sealant for Long Lasting Results
Good technical specifications mean well-respected brands with history. Look for resistance, building codes, food safety, or mould as applicable, movement tolerance and temperature range, movement tolerance, well-defined resistance, and up-to-date resistance. Inspect the product for accuracy regarding the type of cure, cure time, intended use, duration, and other pertinent information.
Conclusion
Selecting a particular type of silicone sealant may be a small consideration from a financial outlay perspective to be made. However, it may pay off significantly over the long term from a cost/benefit analysis of the home. For surfaces prepped properly, surfaces sealed at a professional level, and sealant manufacturers installation guidelines followed, the silicone sealant will provide cost savings over a long period of time in the home and will be significant from a home/money perspective.
Silicone Sealant is available at VDB Adhesives.
