Replacing pressure treated deck boards before staining? To-Do's and To-Dont's.
Since pressure treated pine is the most widely used material for decks, especially here in the eastern states, this is what I will be referring to in this blog post.
KNOW YOUR WOOD
Be sure to know what grade of pressure treated boards you are buying by looking at the label on each of the boards and do your best to match them to your existing wood.
The general rule of thumb on deck board grading is the lower the number, the higher the quality and appearance. 1 (or Select) being the best, 2P (2 prime) the next best, 2 the next and so on. The lower you go, the more imperfections and knots you will see. Take a picture with your phone to have with you as a reminder for when you go to the lumber yard. Actually, this may be the best way do it.
The label should also tell you things like:
• Above or Below Ground Use
• Type of Preservative
• Inspection Information
Below are the most common wood preservatives used for pressure treated lumber.
STAINING
In my opinion, when trying to match existing deck boards to new ones with a semi-transparent stain the longer you can let the treated boards sit out and weather the better (within reason).
Companies are now treating their lumber with micronized copper preservatives (Micronized Copper Azole) which allows you to stain soon after construction (weeks instead of months), but you still have to consider that the new wood will not absorb the stain the same way as the old wood.
My recommendation is to allow the new boards to grey up a little, then complete your deck washing process all at once (opposed to washing the deck before installing the new boards). This will allow your deck washing treatments to be consistent to all wood surfaces.
If you try to stain newly installed boards right away, the result will most likely be the picture to the right.
The stain will just not penetrate the same. No worries though if this has happened to you. We can make it look more uniform a year or two later, when we perform your scheduled deck maintenance.
MAINTENANCE
All decks should have a maintenance schedule that includes a cleaning once a year.
Decks that have a clear waterproofer with no pigment should be recoated every 6 months to a year.
Semi-Transparent stains should be recoated every 1-2 years.
Stains with a high pigment level such as Semi-Solids & Solids will provide the longest protection, anywhere from 3-7 years.