The 3 man crew arrived on schedule and did a quick survey of the equipment and all the duct work in the house. They all wore protective covers over their shoes and laid down protective cloths on the hardwood to protect from the heavy equipment they needed to bring in. I was advised that the overall project would take about 8 hours, as they had to tightly seal all the ducts after cleaning them in order to inject the sealant material to stop the loss of heat or air conditioning from the seams and joints in the ducts. I was able to step out for a couple of hours while they worked without worry, based on past experience with the company. After they completed their work, they showed me the before and after readings of the air loss, indicating a better than 90% reduction. They cleaned up all their work and left the house as they found it. All 3 members of the crew were friendly and professional. I'm very pleased with the work.