When to Perform Vinyl Siding Installation in Bethlehem, PA During Construction As a homeowner planning to build a new house or renovate an existing one, you may be wondering at what point during the construction process should vinyl siding be installed. It is not a question with a straightforward answer since different contractors may have varying preferences. However, in most cases, vinyl siding is installed, by a company such as Window World of Lehigh Valley, after the framing, but before the insulation and drywall are installed. in Businesswith vinyl-siding-installation-bethlehem-pa