Ductwork Installation in Ravensdale, WA

Ductwork projects in Ravensdale typically range from $3,000 to $8,000, depending on scope. A partial replacement of a few crushed or leaking runs is at the lower end. A complete custom-fabricated duct system for a 2,000-3,000 sq ft home with all-new trunk lines, mastic sealing, and R-8 insulation is at the higher end. We provide free in-home assessments with written, itemized estimates.

Yes. The mechanical permit is issued by King County Department of Local Services, Permitting Division (Ravensdale is unincorporated King County), and Washington State requires one for this work. We handle the whole thing — application, fee, and meeting the inspector for the final — so you never contact the permit desk yourself. Every install meets or exceeds the current Washington State mechanical and energy codes.

Most ductwork projects in Ravensdale take 1-3 days. A targeted replacement of a few problem runs is often a one-day job. A complete duct system replacement paired with a new furnace or heat pump install runs 2-3 days, including commissioning and balancing. We schedule to minimize disruption and always leave your home clean.

Almost always, the cause is ductwork: undersized supply, missing or unbalanced damper, kinked flex duct, leaky takeoff, or no return air path. We diagnose the actual cause with manometer readings and airflow measurements — not guesses — and propose the smallest fix that actually solves the problem.

We fabricate our own galvanized sheet metal trunk lines, plenums, and transition fittings. We use rigid metal supply runs wherever possible and limit flex duct to short, properly supported connections at registers. All joints are sealed with mastic (not tape). All ducts in unconditioned space (attics, crawl spaces) are insulated to R-8 minimum. No subcontractors and no shortcut materials.

Often, yes — at minimum, you should have it inspected. A new high-efficiency furnace or variable-speed heat pump can lose 20-30% of its rated performance through leaky, undersized, or improperly sealed ductwork. If your existing ducts are 25+ years old, leaking visibly, or were sized for a smaller previous unit, it's almost always worth replacing or modifying them as part of the equipment install.

There is no natural gas service in Ravensdale, so the realistic choices are propane, electric resistance, or a heat pump. Ravensdale is not listed in the state energy code's design-temperature table, so the nearest station — Auburn, at 25°F — is the starting point (WAC 51-11C-80100, Table C-1), but Ravensdale sits well above and east of the Auburn valley station in the Cascade foothills and runs measurably colder, so we design to a lower temperature and confirm with an on-site load calculation. That is the number a Manual J load calculation for your home is run against, and it is the difference between duct runs sized for the real load and duct runs sized for a guess. At that design temperature a heat pump carries the house, and against delivered propane the operating-cost gap is wide enough that payback usually lands in a few years rather than a few decades. We run your actual numbers rather than quoting a national average.