If you want to complete the construction of your building as quickly as possible with the least amount of error, perfecting the HVAC rough in process is essential. If you want to nail it on the first try, using a company like Aeroseal is your best bet. They outperform traditional sealing methods by a large margin and have a proven track record of speeding up the construction process as well as improving indoor air quality and efficiency of HVAC ductwork in buildings.