What is the difference between water based polyurethane and oil based polyurethane?
Both oil and water based polyurethanes are like a coat of armor for the hardwood floor below, protecting the wood from damage. Each type of polyurethane is a sacrificial layer that will show scratches and wear marks over time, and both oil and water based polyurethane have their strengths! DURABILITY: If each product is applied properly using quality products, the difference in durability is indiscernible. A lot of clients think that water based poly is not as durable as an oil based poly, but a newer brand, quality water based poly will last just as long if it is well taken care of!
COLOR: Oil-based poly has an amber hue, whereas water based poly is clear. An oil based polyurethane will continue to amber and darken over time, while water-based poly will remain clear for the lifetime of the hardwood floor. This color difference is less noticeable over a stained hardwood floor, but an oil based poly will still exhibit an amber hue that will continue to darken over time.
DRYING TIMES: Oil-based poly takes much longer to dry and cure, and only one coat of oil based poly can be applied to a hardwood floor in 24 hours. Water-based poly dries much faster, and several coats (up to 4) can be applied in one day. Water-based poly can be walked on with socks in about 4-6 hours after last coat has been applied, while oil based poly must dry for at least 24 hours before walking on it with socks.
SMELL: Oil-based poly has a very pungent smell and emits a strong chemical odor and noxious fumes while drying that should not be inhaled. We normally advise our clients to be out of the house and also to remove their pets while oil based poly is being applied and drying. Water-based poly, on the other hand, has almost no smell.
Water-based polyurethane will not stink up the house like an oil based poly. It is safe for people and pets to occupy a house while undergoing coatings of water based poly.
THICKNESS AND HARDNESS: Oil based poly is a thicker poly, but it is also softer. Water-based poly, an acrylic product, is a thinner, but harder coating. Oil poly can be more susceptible to dents, while water-based poly can be more susceptible to surface scratching. Because water-based is a thinner product, we recommend 3 coats of water-based poly as a minimum, whereas with oil 2 coats are sufficient as a minimum. For people with large pets, we recommend either 3 coats of an oil based poly or 3 coats of Bona Traffic High Durability water based poly.
COST: Water based poly is a more expensive product. If your flooring contractor is not charging you more for a water-based polyurethane, they are using a cheap brand that will not last!