I built an ocean front beach house on the WA coast. It sits 7ft. above ground atop 16 cement columns. The 6X12 GluLam beams are held to the columns by Simpson GLB’s. They are embedded in the concrete, so can’t be removed. They should probably have been hot dip galvanized, but no rust inhibiting precautions were specified or recommended and foolishly, I took none other than additional paint!
Any ideas on how to retard or mitigate the rusting. Everyone is afraid of getting sued, so my engineer is ignoring me and Simpson is non-committal. I just want the house to stay atop the columns!
Replies
I have had good luck (5 year exposure so far) with the rust-encapsulating rust paints, specifically POR-15. Would take care of the visible surface, problem would be between the bracket and gluelam- where moisture would be trapped.
Anyway to cut out these brackets, and replace with hot galv, epoxy-bolted into the column? Just thinking out loud.
Thanks for the reply! Can you expand on the paint? Brand? Availability? Sounds like a step that would help a lot.
>> Can you expand on the paint?
http://www.por15.com/
If you can manage to wire the brackets together, you might consider installing a sacrificial anode for them.
Thanks for replying! Where do I find details on this option? Wire size, allowable length, annode size & placement? Would it be zinc? I can get to all of the brackets easily to wire together, but am unfamiliar with the details. Would this option work with the rust encapsulating paint? This sounds like a great idea!
I can't give you a lot of details, but if you look for "cathodic protection" on the web you'll probably find something.
I believe that zinc is the usual anode material. Another approach is to actually stick a battery or small DC power supply between anode (buried electrode) and cathode (the brackets). The wire doesn't need to be especially large -- whatever is mechanically strong enough should be OK. Normally the wire should be the same material as the brackets -- ie, steel wire vs copper or aluminum -- and should be welded to the brackets (Thermite welding is commonly used for this). But probably a decent clamp would work OK.
There should be no problem combining the sacrifical anode with the paint -- one protects above the concrete, the other below.