Do we need to paint the bottom of the rainscreen battens – GreenBuildingAdvisor

Ideally you want a vent at both the top and bottom of the rainscreen to allow for air movement. Cor-a-vent SV series vent strips are often a really good fit here, or use perforated channel or even window screen wrapped over the bottom edge of the furring strips. I’d avoid aluminum screen here though as it tends to degrade over time. Fiberglass is better, but more prone to critters chewing through it. My favorite material is stainless steel screen, but it’s the most expensive option.

Edit: somehow I read that as asking about venting, but your title was about painting. I agree with Malcolm that they’d probably be OK in a dry climate, but I’d personally give the last few inches or so a coat of Coppercoat, or at least exterior paint, to help avoid any issues in the future.

Bill