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Seal it right with polyurethane

Polyurethane sealant: The high-performance versatile sealant

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If you’ve been wondering whether polyurethane sealant is right for your job, you need to read this. We’ll answer frequently asked questions and give tips on how to choose and use quality sealers.

The difference between polyurethane sealants and adhesives

Polyurethane is an extremely versatile substance that is used in a variety of DIY and construction jobs. It can be used as an adhesive and can perform much like an epoxy, forming an extremely hard, gap-filling bond. Polyurethane can also be applied as a protective coating for hardwood floors, wood cabinets, and other wood surfaces. But in this article, we’ll explain how to use it as a sealant. Used in this way, Polyurethane retains its adhesive strength and moisture protection, while providing a flexible, protective seal.

Polyurethane sealers are commonly used when you need an extremely durable seal. It’s used in many commercial construction applications such as joining prefabricated building elements, securing joints between water pipe sections, and insulating between precast concrete blocks.

Around the home, a flexible polyurethane sealant is a good choice for watertight seals that need to be painted (as silicone won’t hold paint). That said, it can eventually break down from exposure to UV light and extremes in temperature.

Nevertheless, polyurethane sealant is a tough, long-lasting product that is often the best choice for sealing cracks in masonry surfaces such as block and concrete walls, concrete driveways and sidewalks, and other areas that get heavy use.

Applying polyurethane sealants like a pro

Follow these easy steps to get professional results when applying polyurethane sealants.

  1. Make sure the area you’re sealing is free of dirt, grease, and other contaminants.
  2. Insert the tube into the caulk gun, cut the end of the tube and puncture the foil seal.
  3. Apply sealant in an even bead along the seam or crack.
  4. Use a damp rag or sealant tool to smooth the bead of sealant and seal the seam.
  5. Clean up immediately with a damp rag.

Choosing a polyurethane sealer

When choosing a polyurethane sealant, always choose a premium quality sealant specially designed for the task at hand. As we’ve explained, polyurethane can be formulated with a variety of qualities to fulfill a variety of needs - and you’ll want one that’s just right for your job.

For example, polyurethane sealer can be specially-designed for sealing concrete and metal joints (on sidewalks, pavement, HVAC applications, and so on). This type of sealant remains quite flexible in order to hold up under the expansion and contraction of these materials.

Remember to check whether the sealant you’re considering is rated for outdoor use if you want to use it outside. Another consideration is colour. Make sure what you choose comes in a compatible colour with the surrounding materials.

Looking for a quick fix or repair? Try Loctite Clear Silicone Waterproof Sealant. This multipurpose sealant has great adhesive properties as well. It can be used indoors and out and bonds to glass, ceramics, porcelain, stainless steel, vinyl, marble, and aluminium. It’s great for sealing out weather and for sealing gaskets, shoes and boots. No caulk gun needed!

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