The Homebuyer's HVAC, Plumbing, Electrical & Insulation Inspection Checklist

Why it matters: A full system replacement is one of the largest repairs a home can need — and a general inspector usually only confirms it turns on.

• Find the age and type of the system — Furnace, heat pump, or AC — read the data plate. Past ~15 years, budget to replace.
• Ask for maintenance and service records — No history usually means no maintenance — and a shorter remaining life.
• Check that every room heats and cools evenly — Hot/cold rooms point to sizing, ductwork, or airflow problems.
• Look for rust, corrosion, short-cycling, or loud operation — All signs of an aging or failing system.
• Inspect ductwork in the crawlspace or attic — Disconnected, crushed, or leaky ducts waste money and comfort.
• Confirm permits were pulled for past HVAC work — Unpermitted equipment can mean improper installs and resale headaches.
• Watch for a mismatched system — A new AC bolted to a 20-year-old furnace is a red flag.

Why it matters: A whole-home repipe or a sewer-line replacement can run well into five figures — and a general inspection rarely scopes the sewer at all.

• Note the water heater's age and type — Tank units past ~10-12 years are near end of life. Check for rust or moisture at the base.
• Identify the pipe material — Galvanized or polybutylene (common in older Puget Sound homes) is a repipe risk; copper or PEX is ideal.
• Get a sewer-line scope — The single most expensive surprise — roots and old clay pipe are common here and a general inspection skips it.
• Test water pressure and flow at several fixtures — Weak or inconsistent flow can signal failing supply lines.
• Hunt for leaks and past water damage — Under sinks, around toilets, at the heater, and on ceilings/floors.
• Locate the main shutoff and confirm it works
• Check for a working sump pump — Important for Puget Sound basements and crawlspaces.

Why it matters: An outdated or recalled panel is both a safety hazard and an insurance problem — and bringing service up to code isn't cheap.

• Find the panel's age, brand, and amperage — 100A may be undersized for a modern home; watch for recalled Federal Pacific or Zinsco panels.
• Look for knob-and-tube or aluminum wiring — Common in older homes — a safety and insurability issue.
• Confirm GFCI/AFCI protection — Kitchens, bathrooms, garages, and exterior outlets should be protected.
• Watch for signs of overload — Warm outlets, flickering lights, and power-strip sprawl suggest too few circuits.
• Verify proper grounding and bonding
• Check capacity for what you'll add — An EV charger, heat pump, or ADU may require a service upgrade.
• Confirm permits for past electrical work

Why it matters: Poor insulation quietly costs you every single month, and a general inspector won't measure it — but it's one of the biggest comfort and energy-bill levers in a Puget Sound home.

• Measure attic insulation depth and type — Many older homes fall well short of current Washington energy code.
• Inspect the crawlspace insulation and vapor barrier — Moisture is a constant PNW issue — a missing or wet vapor barrier is a red flag.
• Feel for drafts and air leaks — Around windows, doors, outlets, and recessed lights.
• Check for moisture, mold, or rot — In the attic and crawlspace, where damp PNW air does the most damage.
• Confirm attic and crawlspace ventilation — Proper airflow keeps moisture and mold in check.
• Verify ducts in unconditioned spaces are insulated