Do I use flashing or what?

Tim Stumpf| Posted inGeneral QuestionsonJuly 19, 2012 04:37am

I have a plywood exterior wall and plan on adding house wrap with built in drainage plane, one inch foam board. If I put 1×4 furring strips on the foam what do I use to keep bugs from crawling up the air gap between the foam and the siding?

Answer

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Replies

Aj Builder, Upstate NY Zone 6a|Jul 19, 2012 07:04pm|#1

Add 1/2" of foam between furring. Then some use stapled in fold of screen. Done. Next.
Expert Member

Malcolm Taylor|Jul 19, 2012 07:45pm|#2

Here in BC, where all construction in coastal areas has to include a rain screen, builders have moved away from folding insect screen at the bottom of the cavity, as it is very susceptible to damage and very difficult to replace. Instead we use a U or L flashing made of perforated material. They are commonly available here, but you may need to get one made up where you are.
With a 3/4" air space It might be a good idea to check with your local building inspector, as codes differ in how they require the cavity to be terminated at the top. sometimes firestops are required for a gap that deep.
Tim Stumpf|Jul 19, 2012 11:08pm|#3

Thanks
GBA Editor

Martin Holladay|Jul 20, 2012 06:12am|#4

Tim,
Most builders use insect screen. If you are worried about the durability of the insect screen, you could use this product from Cor-a-vent:
http://www.cor-a-vent.com/siding-vent-sv-3.cfm