Site information

Sources & Methodology

How estimates, ratings and building guidance are handled.

Assembly evidence

Sound ratings apply to specific tested assemblies. We do not transfer a result to different construction without qualification.

Cost estimates

Calculators use user-entered ranges and simple geometry. They do not create quotations.

International use

Building, fire, housing and condominium requirements vary. Local authorities and professionals take priority.

Updates

Pages avoid unstable product rankings and unnecessary current prices.