A standard home inspection confirms systems 'turn on.' It rarely tells you whether the HVAC is sized right, whether the sewer lateral is cracked, or whether the water heater is code-compliant. Use this checklist before you buy, and the California point-of-sale list before you sell. Anything you can't confirm yourself is worth having a licensed technician verify while the price is still negotiable.
Before you buy: what to inspect
Heating & cooling (HVAC)
- Age of the furnace, AC, or heat pump and the date of last service
- Whether the system is sized correctly for the home (over- and undersized both fail early)
- Ductwork condition and sizing, plus adequate return air
- Refrigerant type — older R-22 systems are increasingly costly to service
- A clear, properly routed condensate drain line
- Evidence the last changeout was permitted (HERS documentation in CA)
Plumbing
- Pipe material — galvanized or aging pipe often means a repipe is coming
- Water pressure — too low suggests corroded pipe; too high blows out fixtures
- A sewer-lateral camera scope for roots, cracks, and bellies (the costliest hidden surprise)
- Active or past leaks under sinks, around fixtures, and at the water heater
- Shutoff valves that actually operate
Water heater
- Age, type (tank vs. tankless), and capacity for the household
- Seismic strapping and a code-compliant T&P discharge
- Signs of leaks, corrosion, or sediment
Water quality
- Hard-water scale on fixtures and glassware
- Any existing softener or filtration — age and condition
- Discolored or odorous water
Indoor air quality
- Duct cleanliness and any disconnected or asbestos-wrapped runs in older homes
- Attic insulation depth, even coverage, and air sealing
- Signs of moisture, mold, or rodent contamination
Before you sell: California point-of-sale items
California requires certain items to be addressed when a home changes hands. Confirm the specifics with your agent and local jurisdiction.
California point-of-sale requirements
- Water heater seismic strapping (Health & Safety Code §19211) — required
- Water-conserving plumbing fixtures in homes built before 1994 (Civil Code §1101 / SB 407)
- Working smoke alarms and carbon-monoxide alarms (Health & Safety Code)
- Disclose known unpermitted work — HVAC changeouts, water heaters, repipes, and sewer work commonly surface
- Check whether your city requires a sewer-lateral inspection or compliance certificate at sale
Why your agent may not request a specialist inspection
This isn't about bad agents — plenty encourage it. It comes down to incentives: an agent is generally paid only when the sale closes, and the standard home inspection is built to confirm systems broadly function, not to surface the system-level detail that can complicate a deal. The result is that the most expensive repairs — HVAC, plumbing, and the roof — are the ones a generic inspection underweights. After closing, that cost is yours.
Specialist inspection vs. a standard home inspection
A general home inspector is a great once-over of the whole property. A licensed HVAC and plumbing professional is the specialist for the systems that quietly drive your comfort, energy bills, and repair budget — sizing and ductwork, a sewer-lateral camera scope, water-heater code compliance, and water and air quality. Both have a place; for the costliest systems, you want the specialist before you're locked in.
Buying or selling? Get the systems checked before you're locked in.
Frequently asked questions
Does a standard home inspection cover HVAC and plumbing?
Only at the surface. It confirms systems power on and broadly function — it isn't designed to evaluate HVAC sizing and ductwork, camera-scope the sewer lateral, or verify water-heater code compliance. A specialist verifies the parts that actually drive your repair costs.
Should I schedule a systems inspection before or after closing?
Before — while findings are still negotiable. Once you close, every repair the inspection would have caught becomes yours to pay for.
What do California sellers have to fix before selling?
Common point-of-sale items include water-heater seismic strapping, water-conserving fixtures in pre-1994 homes, and working smoke and carbon-monoxide alarms — plus disclosing known unpermitted work. Confirm specifics with your agent and local jurisdiction.
Keep exploring
Reviewed by John Stevenson Plumbing, Heating & Air. Reflects how we evaluate a home's systems before purchase and the California point-of-sale items most relevant to plumbing and HVAC (water-heater strapping per H&S §19211, water-conserving fixtures per Civil Code §1101/SB 407, smoke/CO alarms). Point-of-sale and local ordinance specifics vary — confirm with your agent and local jurisdiction. Verify any contractor license at the Contractors State License Board (cslb.ca.gov). Last updated 2026-06-25.