Follow a step-by-step process: mark the location, drill holes, insert anchors, and secure the box for a weatherproof fit. Apply weatherproof sealant around the box edges and cable entry points to prevent water ingress. Perfect for electricians & DIYers. Selecting the correct box. This video provides a detailed guide to concealed electrical wiring during house construction. From marking the wall to fixing the distribution box, we cover every crucial step to ensure your home's wiring is safe, long-lasting, and fault-free. Don't let your electrician skip these critical steps!You achieve the best results mounting a waterproof electrical box on brick or concrete when you use the correct tools and high-quality materials. For outdoor installations, a pancake.