A sealant is one of the essential parts of your double glazed window. The sealant seals the whole structure to make sure it keeps you and your loved ones safe and comfortable. Properly sealed double glazed windows guarantee the tightness of the whole structure. Sealant companies use organic sealants to ensure air permeability. Several sealants can be used for double glazing windows, including polyurethane, hotmelt, polysulphide, and silicone. The sealants are combines with PIB, which is a spacer bar edge. Keep reading to discover what sealant is used for double glazing.

2-Part Sealant

The standard 2-part sealants include polysulphide, silicone, and polyurethane. They consist of a base material, also known as 1st part and a hardening material known as 2nd part. These sealants are mixed in a measured ratio. The mixture is also cured for about 2 to 3 hours to guarantee a solid finish. Once cured, it is set and cannot be altered. Since the 2-part sealant creates a cross-link between the glass surface and sealant, it cannot be pulled off the glass. It will leave a residue on the glass surface if you try to pull it off.


Polyurethane is relatively cheaper than other sealants, thanks to its reactive nature. However, this sealant has high machinery costs. Sealant companies usually use the sealant for double glazing.


Polysulphide sealant is widely used for double glazing since it is low machinery maintenance. This sealant has excellent resistance to argon diffusion and moisture penetration. Moreover, it is resistant to wear and tear.


Since silicone is UV resistant, sealant companies expose the edge seal to UV. However, it is the worst-performing sealant in terms of gas loss and water ingress. As such, the PIB or polybutylene has to be consistent. Silicone sealant is commonly used in several tall buildings.


Hotmelt is a single component sealant. Since it is a thermoplastic, hotmelt can be heated and cooled down. It flows when hot and becomes solid when cold. The sealant does not change its state during the process.

How to Choose a Reliable Mastic Man

A mastic man repairs broken surfaces and joints. During the repair, the mastic man will use various tools and silicone. Silicone is preferred due to its ability to resist water and mildew. Do you want to have your double glazed windows repaired? Here is how to find the best mastic man near you.

  • Reliability

It is crucial to pick a mastic man you can rely on to offer quality anti-fungal silicone. Such a mastic man will help you save money by extending the durability of your double glazed windows.

  • Ask for Quotes

Make sure that you choose an affordable mastic man. Ask the mastic man to send you free quotes before making the final choice.

  •   Check the Certification

Another vital aspect you need to put into consideration when looking for the best mastic man near you is the certification. Hire a certified mastic man to enjoy professional services. You can ask for copies of certification to be sure.

Contact the leading sealant companies if you are looking or the best sealant for your double glazed windows.

Sam Allcock