Help, My Pole Barn Home Poles Are Rotting
Reader HEATHER in HELENA writes:
“I was encouraged to email you regarding my current situation. A couple years ago I bought an unfinished pole barn home. Construction originally began in 2012. While recently doing some improvements to some interior posts I discovered that the nearest pole had wet rot below ground level. The rot has compromised the surface of the pole. The poles were coated with a rubber coating called Blackjack 57 but it appears to be failing. I had a general worry about this but now I know it’s the case. My guess is all the poles are in similar condition or will be at some point. The poles are still salvageable and so I am hoping to find the least invasive and hopefully cost effective way of addressing this issue. I have been studying chemical treatments which may stop the rot and preserve existing wood, but am not sure how effective that would be. I am now living in the building so access to the poles would be limited to the outside. There are approximately 26 poles.
Do you know of a contractor who can help or any possible solutions?”
As properly pressure preservative treated wood (UC-4B rated) will outlast anyone alive on our planet (https://www.hansenpolebuildings.com/2020/09/pressure-treated-post-frame-building-poles-rot/), it leads me to believe your columns are what is typically found at local lumber yards and big box stores and should never be used structurally in contact with ground (https://www.hansenpolebuildings.com/2014/05/building-code-3/). It is likely whoever began this build was aware of having improperly treated wood, so in an attempt to solve this, they applied Black-Jack™ Rubr-Coat 57. While an excellent foundation waterproofer, I will guess it was applied to wet wood and/or not thoroughly sealing columns in areas prone to decay. It has probably made the situation worse, by trapping water, yet allowing oxygen to still reach wood.
As you can access columns from outside, I would look towards cutting off columns at grade, removing affected areas from ground, then fill area with concrete, using a Code approved wet-set bracket to attach the remaining column to piers. This will be fairly labor intensive, however getting under treated wood out of the ground is your best solution.
If not up to performing this yourself, try posting on Craigslist under “Gigs” to find local help.