Exterior Wood Trim Painting
Here is a trivia question for you – How often should you repaint exterior wood trim? The answer is every 5-7 years. That is not the answer you will get on most paint cans or from the coating manufacture. Most claim their paint will last 15+ years and this is possible with proper preparation on vinyl or aluminum. However, this is not possible on wood that is exposed to temperature changes, UV rays, and rain on a regular basis. Wood is constantly moving, have you ever heard your house creak or settle? This is not the case with vinyl or aluminum. The extra movement of the wood creates micro fractures in the coating, which allows moisture to absorb into the wood. The extra movement in the wood also makes the wood swell, which causes more fractures in the coating and effectively cuts the coating lifespan in half at best. If you do not believe me, try to get Sherwin Williams or BEHR to provide a warranty for the paint 7 years after applying it!
Why Every 5 Years?
I strongly recommend repainting exterior wood every 5 years. As the coating starts to breakdown and fail the bottom layers become increasingly disbanded from the wood and a weaker bond forms between each coat. If they are recoated before they fully start to break down, they will have a better chance of holding on after they have been recoated. This will make the wood last longer as well as making the next application of paint require less time consuming scraping, which will drive cost up.
In short, by trying to stretch the time between each paint coating from 5 years to 7 years, you will most likely cost yourself more in the long run and have a house that looks like it needs to be painted for part of the time as opposed to always looking good at no real extra cost.