No two jobs or ducts are alike, but we can generally breakdown of the factors which impact schedule.
Demolition executes relatively quickly. A competent crew can strip, remove and dispose of old failed insulation in less than a week for most duct systems. Access to dumpsters really matters for disposal. Bags hand carried down a building and to a remote dumpster can add significant time.
Measurement can be completed for most ducts in 1-2 days, mostly depending on the distance of the job site from the installer, access to the roof and weather conditions. Add another day on the backside for translation of field measurements into computer modeling software.
Fabrication depends highly on the size and length of the duct, the amount of straight duct and the number of bends. Elbows and transitions with multiple bends or angles add time. Many ducts can be fabricated in about five to ten business days.
Staging of the materials should add one to three days, depending on the amount of material to be staged and the relative accessibility of the roof. Materials can be lifted by rope, by scaffold, by a lull or by crane in order of slowest to fastest. Use of a lull offers the best compromise between speed and cost. Delivery times depend obviously on the proximity of the job site to the factory in the Philadelphia area.
We try to minimize the time from stripping to installation to help customers avoid a fully exposed and uninsulated duct in the elements.
Installation times depend on several factors, including:
- Height of the duct off the roof
- Size of the duct
- Length of the duct
- Number of access doors in the duct
- Number of curves in the duct
- The type and size of the supports for the duct itself
- Accessibility of the roof
Let us assume that the customer needs a two-foot-high by three-foot-wide duct system. Expect the sections of Techna-duc® to come in sections four to eight feet long. A competent install crew can install two to four sections of insulation per day per technician assigned. A two-person crew could reasonably expect to install four to eight sections in a normal day, or essentially sixteen to thirty-two linear feet of duct per day in ideal conditions. Ducts that run vertically down the sides of buildings obviously take a lot longer and depend highly on access and lift availability.
Ducts high off the roof will be slightly slower. Extra access doors or excessively thick angle irons in the supports will also slow the install from extra field modification of the panels needed to accommodate these features.