Oil vs. Water
The main differences between water based and oil based polyurethane is drying time, odor, price, and color---not durability. Water-based finishes can cost two or three times as much as oil-based finishes. Most of the existing site finished wood floors are oil based finishes. Prefinished wood can be water or oil based. If you have site finished wood in your home, it is probably oil based. Be aware that if you change to water based, it will look different.
Oil Modified Polyurethane (OMU)
**Is a solvent based polyurethane, contains mineral spirits
**Much higher in VOCs (Volatile Organic Compounds)
**Ambers (yellow, brownish-orange tones) over time
**Odor (can linger for several days or even weeks)
**Oil interacts with the wood for warmer tones. Gives the wood more depth and color. This is because it is absorbed into the wood and the oil accentuates the wood grain, giving the grain more presence. The natural oils in the sealer also give the wood a muted shine.
**Only option for dark stains
**Drying time per coat is at least 8 hours (high humidity, low temperature, lack of air movement cause this to vary—sometimes 24 hours plus is needed!) Need to wait overnight between coats
**Curing— allow finish to cure for one week before heavy foot traffic and 30 days before placing area rugs. The floor may be walked on (light foot traffic only!) and furniture replaced after 24 hours, but remains susceptible to scuffing and marring until completely cured. Use only a dry microfiber mop or cloth for cleaning during the first week or two—no liquid cleaners!
Water Based/Water Borne Polyurethane
**You can conceivably do a coat every 2--3 hours. This takes 1—2 days off the job versus oil based poly which allows the homeowner to get back to their routine/life sooner
**Any given coat will dry enough in a few hours so that the owners can walk on it
**Cost is more expensive (additional charge to use)
**Curing--70% cured after 1 day, 90% cured after 3 days, fully cured in approximately 7 days. Do not replace area rugs until floor is fully cured. The floor may be walked on and furniture replaced after 24 hours, but remains susceptible to scuffing and marring until completely cured. Use only a dry microfiber mop or cloth for cleaning during the first week or two—no liquid cleaners! Do not replace area rugs for at least two weeks after coating
**Slight fumes/odors. The day after the final coat most people smell nothing
**Best for natural and light to medium stains, not dark stains
**Because is sets up so fast, there is little penetration into the wood
**Feels/looks more “plastic”; tends to have greater reflection and shine
**There IS a difference in brands. There is a much wider range in quality and durability with waterborne than oil based. Higher quality water borne brands have been proven to wear as well as oil.