ANSWER:
Refinishing furniture in a space that is below or above the 65*-75* F range can lead to problems, and a space below 55* F is definitely too cold. One issue caused by cold temperatures is the development of dimples in the finish called "Orange Peel".
The colder your space it is, the longer you have to wait between coats. Cold temperatures slow the dry time and affect how quickly the finish will level and harden. Our easy rule of thumb is; if it's cold enough to wear a sweater it's too cold to apply a water based finish.
If you must apply WATER BASED TOP COATS in cool conditions, GF suggests that you add Accelerator to speed water evaporation from the finish. Make sure the finish and the surface of the piece you are working on is at room temperature. You can warm up the finish by placing the can in hot water for 5 minutes beforehand, and if possible, move the piece back into warmer temperature after applying finishes for the 7 days of cure time.
OIL BASED finishes are not as affected by cooler temperatures, but lower temps will still slow the oxidation of the finish. GF again suggests moving the piece back into warmer temperature after applying finishes for the 7 days of cure time. You can apply oil based finishes in as low as 60 degrees if necessary.
Warning: Applying OIL BASED finishes near an open flame combustible heater is VERY DANGEROUS. The mineral spirits mixes with fumes from kerosene, for example, creating an unsafe environment. If you choose to work with a kerosene heater, it would best to heat the garage first, turn off the heater, then apply the finish. Next, air the garage completely before turning on the heater again. Better yet, use an electric heater. We recommend NOT using open flame heaters because of the risk.
Conversely, if you are working in HOT, DRY climates any WATER BASE finish will dry faster. GF Extender can be added to water based products to increase dry time in those situations.
Ideal conditions: 70*F and 70% humidity
Ideal temperature to store product: 65-75 degrees. Garages are not a good place to store any finish.
NOTE:
We've been asked whether it's OK to paint in a 50* F shop if the paint is stored at a safe temperature beforehand, and the finished piece is moved into a room with a safe temperature to dry. General Finishes believes that this approach might work, but it's risky. Instead, GF recommends that you create a space in a room with a safe temperature.