LET’S BE SPECIFIC ABOUT SEALANTS

Interior Conditions

While there are a range of sealant products available that could be used for glazing installations, many of the products will not be completely suitable for the application. Using such a product can result in poor performance and call-backs to address issues, even on relatively recent jobs.

First and foremost, it is important to ensure that the sealants you are using are of a high-quality. While it may be tempting to look for a lower cost option, especially with increased costs and pressure on profit margins, this can be counter-productive. Cheap products will generally not last as expected, even when applied correctly in ideal conditions. This can become a serious issue if the failure of a low-quality sealant is assumed by the customer to be poor workmanship and the reputation of the business is damaged as a result.

One of the reasons why low-cost silicone sealants may fail is that they are often bulked out with other chemicals that evaporate as it cures, causing the sealant to shrink and not form a strong bond. The best way to ensure a quality product is to only use those developed and manufactured by trusted and reputable brands.

In addition to the quality, when selecting a sealant or sealants specifically for glazing installations there are a number of factors that must be considered.

Weather

For exterior applications one of the biggest challenges is, of course, the weather conditions that the glazing, and therefore the sealant, must withstand over its lifetime. It will be exposed to ultraviolet (UV) radiation from the sun as well as wind, rain and significant changes in temperature.

The sealant needs to have the durability and weather resistance to withstand these conditions season after season. This is now more important than ever as the weather in the UK looks set to become more extreme with higher summer temperatures, more intense rainfall and more frequent storms.

Similarly, the sealant used on internal surfaces will need to meet specific requirements based on the conditions inside. As homes, workplaces and other buildings become increasingly airtight to ensure energy efficiency, humid air and the condensation it causes can be a particular challenge. Any frequent or prolonged presence of condensation can allow mould and bacteria to form and spread. This is also a concern in environments that are naturally more humid due to how the space is used. For example, leisure centres and swimming pools. This issue can be addressed by selecting a high-quality sealant that contains an effective fungicide to prevent the growth of mould.

Movement Resistance

The nature of glazing means that there will always be movement between the glass and frame and between the frame and the rest of the building. Changes in temperature will also cause the frame and glazing to expand and contract over time. The sealant needs to maintain a degree of permanent flexibility to ensure it can accommodate these movements over the long term.

Substrate Suitability

Furthermore, it is important to consider the substrates that the sealant will be applied to. For glazing applications this can be a wide variety of materials. For example, in addition to the glass of the glazing, the frames may be manufactured from PVC-U, aluminium, steel or timber depending on the project or area of the building. The sealant used around the frame may also need to adhere effectively to brick and stonework as well as wide variety of façade materials including modern composites.

WHICH TYPE OF SEALANT TO CHOOSE?

There are several different broad types of sealant, which are based on different chemistry, and therefore have differing properties. Considering all the performance requirements for glazing applications, silicone-based sealants are ideal. A highquality silicone sealant will deliver a flexible seal, adhesion to the wide range of common substrates and excellent resistance to the effects of weather, UV and changes in temperature. This means it will not crack, shrink, craze or discolour for a longerlasting finish that retains its appearance and performance in the long-term.

However, it is recommended that professionals look for a silicone product that has been developed specifically for use on glazing installations, such as Trade Mate Glazing Seal and Trade Mate Frame Seal. By choosing a glazing-specific sealant professionals can be sure that it has been formulated and tested with the specific materials and conditions in mind.

Another type of sealant that will be especially suitable for certain applications is MS Polymers. Sometimes referred to as hybrid sealants, MS Polymers have the permanent flexibility, versatility and UV and weather resistance of silicone products while also being over-paintable. Due to the formulation of MS Polymers, they can also be successfully applied in a wider range of conditions.

While MS Polymer products typically cost more than a silicone alternative, they can provide a solution to specific project requirements. For example, it may be necessary to match the colour of the sealant to the specific finish of the window or door, which is simple to achieve with a MS Polymer based product, such as Trade Mate Paintable Frame Seal, that can be painted over in the required colour. Also, MS Polymers are ideal for repairs as there is no need to fully dry the surface before it is applied.

While there are a range of sealants on the market, choosing products from trusted brands that have been developed specifically for the type of application will ensure a long-lasting high-performance result.

To find out more about Geocel’s Trade Mate range of high-quality sealants visit: www.geocel.co.uk.