Expert: Bruce E. Johnson - 7/18/2009

Question
QUESTION: http://i207.photobucket.com/albums/bb153/sgull1/IMG_1133.jpg
http://i207.photobucket.com/albums/bb153/sgull1/IMG_1135.jpg
http://i207.photobucket.com/albums/bb153/sgull1/IMG_1134.jpg

Hi Bruce,
The above links are to photos of 2x4 boards installed on the roof of a facility that houses birds, and underneath these "slats" is the bird habitat area (the open slats like this allow for for natural light and rain, etc. in the habitats below). As you may be able to see by the color, these boards are rather old and weathered, and for the sake of protection and appearance it has been recommended that all these boards be stained with oil-base Olympic type stain. Looking closely at the boards, it is apparent that they are already treated lumber, as there are the tell-tale half-inch slits/perforations throughout. My question is whether you would think that staining the boards as I mentioned would provide much additional physical protection/preservation of the wood (other than just appearance), or if you would think that because it's already treated lumber that the wood is probably as protected/preserved as it's going to get considering it's present condition and the application here. Or, if protecting/preserving the wood to last longer is the primary goal but secondarily the appearance, might you suggest I would instead use something like Thompsons weather-seal or similar instead of just Olympic type outdoor wood stain?  thanks



ANSWER: Hi Steve, pressure treated wood will have a stamp on it and a greenish or bluish hue.  It will wash out over time and bleach out.  It is hard to say from the photos if the wood is pressure treated, however it appears to be in good condition.  A good sealer is definitely in order. This wood is ripe for a good penetrating sealer, it is dry, it is like a sponge.  Drench it with Thompsons Water Seal (or acceptable substitute), it will soak in and give you good service over many years if applied on a regular basis.  The only reason to add color or stain to the wood is if you require a darker color or want to change the color.  When choosing a stain, get one that is penetrating and sealing.  In your case, be sure to follow manufacturer's instructions concerning fumes and how they may interact with the bird population.  A complete aeration of all fumes may be critical.  I hope this information helps please feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com

---------- FOLLOW-UP ----------

QUESTION: Thanks Bruce for your reply.  As followup, I just wanted to mention that the boards are definitely pressure treated, but has probably never had any sealer/stain applied since it was originally installed years ago. It is quite dry and will probably soak up a lot of sealer/stain when I go to apply it. We have a good supply of the following specific product on hand, and I was wondering whether you would think this would be penetrating/sealing enough or whether you would suggest should I use something more like Thompsons water seal instead:
http://www.superdeck.com/Superdeck-Products/Semi-Transparent-Deck--Siding-Stain/

Also, in addition to sealing, I do want to change the color of these weathered boards to closely match the redwood colored stain I mention above, so in that case would it be best to use the product I mentioned above or somehow add coloring or stain to the Thompsons water seal. Or stain, then add the Thompsons water seal?

Answer
HI again Steve, the Superdeck product you mention will suffice for stain and sealer.  Just find the color you want and use this product in a one step application.   I hope this information helps please feel free to write again regarding this or other matters, sincerely bruce e johnson..bejohnsonconsulting.com