Redecking a short timber bridge, pressure treated vs. not? - Ask Extension
I have a 28 foot long, 14 foot wide bridge on my driveway crossing an irrigation ditch. The ditch is scheduled to be put into a pipe in 8-10 years. I ...
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Redecking a short timber bridge, pressure treated vs. not? #744286
Asked April 14, 2021, 12:17 PM EDT
I have a 28 foot long, 14 foot wide bridge on my driveway crossing an irrigation ditch. The ditch is scheduled to be put into a pipe in 8-10 years. I must redeck it now, and am asking: Is it reason to use local milled not-pressure treated lumber for the deck?
Hood River County Oregon
Expert Response
Hello Gens,
Given how important it is that the bridge decking retain its structural properties over time, and the fact that the wood is in an environment where it will sustain prolonged periods of wetting and drying, I would recommend the use of pressure-treated wood.
Even just for 8-10 years, the durability of wood can be so highly variable that I think the risks are too great to take the chance of decay or insect attack that would lead to premature failure.
Given how important it is that the bridge decking retain its structural properties over time, and the fact that the wood is in an environment where it will sustain prolonged periods of wetting and drying, I would recommend the use of pressure-treated wood.
Even just for 8-10 years, the durability of wood can be so highly variable that I think the risks are too great to take the chance of decay or insect attack that would lead to premature failure.
