Bugged By Bugs
Reader FRANK in ARVA, ONTARIO writes:
“I am actually in Ontario. How to keep bugs from getting behind the steel wall siding voids in the area left behind where the ribs are? Interior is finished with vapor barrier/batt insulation/osb. Exterior has steel “barn” siding and Tyvek wrap underneath. Z flash at bottom of exterior wall siding at bottom over pressure treated skirt board. Built mid- 90’s by myself. I left 1/16 ” gap from bottom of wall siding to top of skirt board z flash to allow water drainage and so no intimate contact between the wall and flashing to help avoid rust issues. All steel edges had a layer of prime and paint added during build. 30 years later no rust. Lady bugs and earwigs like to accumulate in these rib hollows. Don’t want to caulk bottom of siding…might trap moisture. Any suggestions? Thanks in advance.”
Mike the Pole Barn Guru writes:
In my world it is Asian Beetles getting between wall steel and building wrap. No matter how tightly I have exterior skin sealed, they seem to find a way to migrate in and then expire. I am not sure, as of yet, how to calculate added R-value from their bodies.
Unless your build has some serious issues with poor flashing around openings, you should not have water accumulations between steel siding and your Tyvek. You can check for this by looking for signs of water on your Z flashing at base of wall. Most often, best way to “bug seal” your siding would have been to place inside closures (https://www.hansenpolebuildings.com/2015/12/the-lowly-inside-closure/) at top and bottom of each sheet of walls steel, as well as above and below openings. While this is easy to accomplish at time of construction, it would prove to be a task from where you are now. Chances are these little critters are not going to adversely affect anything, so after 30 years, you may just need to accept they are going to find a home there.