A whole house renovation is an extensive project that involves major changes to the main elements of your house. This usually requires the removal of interior finishes to start from scratch but sometimes certain finishes can be retained depending on the scope of the work and the extent to which the interior design will be altered. Elements that can be salvaged include wall surfaces, trim work, and flooring that are still in good condition as well as most mechanical systems such as plumbing, electrical, and HVAC units.