Connect to your favourite weather forecaster and look for the following conditions:
Category: Finishes Product: Water Repellents for wood and masonry
Temperature Limitations: Use above +10 C (+50 F) and below + 35 C (+95 F)
Rain Limitations: No rain for 48 hours
Wind Limitations: n/a
Humidity Limitations: High humidity will slow curing time
Continuous Conditions: 48 hours no rain. 72 hours no freezing.
Comments: To apply water sealers to either wood or masonry, both the surface and the liquid must be above freezing and stay there for 48 hours. Rain will not penetrate the sealer, but can cause water marking if it arrives before final curing. Some products must go on a dry surface, others can go on a damp (no standing water) surface. Some require no freezing for 72 hours.
Weather limitations on most renovation products can be located on the WEATHER tab above.
APPLICATION / INSTALLATION DETAILS
Water repellents are primarily designed to prevent or restrict the penetration of water into a material, hence protecting it from wet/dry cycles as well as the extra damage caused by freeze/thaw cycles when a material is saturated with water.
They have little to do with stopping rot or moss. For wood they slow down the aging of the wood by reducing the cracking (checking) and splitting of the wood and if they contain UV filters they can help to slow down the greying of the colour.
For masonry they can help to stop spalling, the popping off of the surface caused by ice formation just below the surface.
For both they stop barbecue sauce from soaking into a surface, making it far easier to clean it up without leaving a mark.
As with paints and stains it is important to remember the cardinal rule for avoiding lap marks with liquid applications -- work wet-on-wet.
Click here for doing that outdoors.
Click here for a general overview of deck finishes.