T tomtheelder2020 Member Joined Mar 8, 2020 Messages 11 Reaction score 1 Location 95620 Jun 19, 2020 #1 My 70 y.o. exterior siding is redwood shiplap. The original primer was lead-based so I won't be using that. I live in CA so oil-based primers are not available. Recommendations for a primer that won't bleed through will be appreciated. Thanks.