The Differences Between Silicone Sealants and Polyurethane Sealants

One of the principal differences between silicone and polyurethane sealants is the chemical composition. Silicone is an inorganic substance, while polyurethane is organic. The primary difference between organic and inorganic substances is the presence of carbon. Polyurethane is a polymer, which comprises of a series of organic atoms connected by carbamate. Silicone is a unique material because it contains both inorganic and organic compounds.

The chemical differences make the lifespan of each sealant quite different. Typically, you can expect a polyurethane sealant to last 5 to 10 years, and the exact lifespan will depend on how much sunlight it was subjected to, the changes in temperature, and how often it needed to expand and contract. Silicone sealants will typically last at least 20 years, and many manufacturers even offer 20 year warranties to protect you in case your sealant wears out faster.

While silicone sealants typically about twice as long as polyurethane sealants, they also typically cost about twice as much. However, the initial cost of materials isn’t the only consideration to make when calculating the true cost. You’ll also want to factor in labor costs. Each type of sealant takes about the same amount of time to install, but you’ll need to install polyurethane sealants at least one additional time before the silicone sealant wears out. Therefore, in reality, labor cost for polyurethane sealants is at least double that of silicone sealants.