Standard home inspections are broad but shallow. The inspector turns on every faucet, flushes every toilet, checks the water heater shutoff, and notes whether anything visibly drips. That's 90% of what a standard inspection covers — and for the older SFV housing stock (Sun Valley, Arleta, Pacoima, Van Nuys, Reseda, and similar post-war tract developments), it misses the five most expensive plumbing problems you're about to inherit.
If you're under contract on an older SFV home, here's what to check in your inspection contingency window.
1. The Sewer Lateral (Camera Inspection, Not Surface Observation)
The most expensive single thing that can go wrong with the property is the sewer lateral. Standard home inspections do not include a camera inspection of the sewer line — it's explicitly excluded from the scope of 90% of inspector contracts.
A dedicated sewer camera inspection costs $275–$450 and tells you whether you're buying a functional lateral, a root-invaded mess, or an Orangeburg pipe on the verge of collapse. This one test has saved LA buyers tens of thousands in undisclosed repair costs more times than we can count.
What it finds:
- Root intrusion (standard in pre-1970 homes)
- Cracked or offset clay pipe
- Orangeburg tar-paper pipe (1940s–50s — unlinable, full replacement required)
- Lead segments (pre-war homes)
- Bellies in the line (sagged sections)
- Illegal or non-code connections (rainwater downspouts into sewer, etc.)
2. The Supply Pipe Material
The #2 expensive problem in older SFV homes is galvanized steel supply pipe — in most pre-1965 homes, it's the default. A standard inspector notes material where visible (at the water heater, under sinks, at the main shutoff) but may miss:
- Whether the whole house is galvanized, or only part (partial copper upgrades in the 1970s–90s are common).
- Whether dielectric unions were used where galvanized meets copper (galvanic corrosion without them).
- Actual condition (inside a pipe can't be seen — corrosion is interior).
Ask the inspector to note the material at every visible location and magnet-test to confirm ferrous (galvanized) vs non-ferrous (copper, brass). If galvanized is present, factor in a $7,000–$15,500 repipe cost into your offer negotiation.
3. The Gas Line System
Especially relevant in Sylmar, Northridge, Granada Hills, and anywhere affected by the 1971 and 1994 quakes. A standard inspection doesn't pressure-test gas lines. Slow leaks from earthquake-damaged joints can be totally invisible until someone does an actual test.
A C-36 licensed gas line inspection ($275–$450) includes a 10 PSI pressure decay test that catches leaks too small to smell. For any pre-1980 SFV home, this is worth the cost as part of your inspection contingency.
4. The Water Heater's Real Age
"Water heater present, functional" is what a standard inspection will tell you. What it won't tell you:
- Actual manufacture date (read the date code on the rating plate — 1st two or last two digits of the serial).
- Whether it's been flushed routinely (pull the drain valve at inspection — if water is brown and full of sediment, the answer is no).
- Anode rod condition (a blip of corrosion on a magnet-retrieved end of the anode tells the story).
- T&P valve testing (most inspectors don't operate the T&P; we do).
A water heater with 2 years of visible life left should factor into your offer. A tank already 10+ years old should be a $2,500–$3,200 negotiation item.
5. Slab or Foundation Leak Indicators
For slab-foundation SFV homes (very common in Arleta, Pacoima, Sun Valley):
- Walk the floor barefoot. Any warm spots? Could be a hot-side slab leak.
- Look at the water heater's run frequency if the HVAC is off. If it's cycling often with no usage, supply is leaking somewhere.
- Ask for 12 months of water bills from the seller. Steady usage should produce steady bills; sudden jumps can indicate a slow-onset leak.
Slab leak repair in an existing home ranges from $1,800 (attic reroute) to $5,500+ (slab break-in). Not the deal-killer galvanized can be, but worth factoring in.
What an Extended Pre-Purchase Plumbing Inspection Looks Like
A proper pre-purchase LA plumbing inspection takes 1.5–2 hours and includes:
- Sewer camera inspection from cleanout to city main, written report.
- Supply pipe material audit — every accessible location documented.
- Gas line pressure decay test.
- Water heater age verification, flush sample, visual condition assessment.
- Pressure regulator test and static pressure reading.
- Visible drain inspection at every fixture for flow rate and slope.
- Slab foundation thermal scan for high-suspicion properties.
- Written report with photos, recommendations, and estimated repair costs for any defects found.
Total cost: $475–$750 depending on home size. That's usually under 1% of the purchase price — easiest money ever spent on an LA home.
Book a pre-purchase plumbing inspection
Plumbing Geeks is C-36 licensed, family-owned, and dispatches 24/7 with no overtime charges. We serve the San Fernando Valley and the rest of the San Fernando Valley and Greater LA from our Sun Valley base.