California's Transfer Disclosure Statement: What Plumbing Problems You're Legally Required to Disclose When Selling

Published by Clément Lacaille, Tech-Bharat · Updated September 7, 2026 · How we research

If you're getting ready to sell a home in California, one form asks you to put in writing everything you know about the plumbing: past leaks, repairs, that slow drain you've meant to deal with for two years, whether the water heater is strapped down. That's the Transfer Disclosure Statement (TDS), and getting it wrong — not through fraud, just through not thinking carefully enough about what you actually know — is one of the more common ways a home sale turns into a lawsuit after closing.

What the law actually requires

California Civil Code §1102 and following sections require most residential sellers to complete a TDS and deliver it to the buyer, either before they make an offer or within three calendar days of an accepted contract if it's delivered afterward. The form walks through the home system by system — structural, roof, electrical, and plumbing among them — and asks the seller to check whether each one is in working order and to explain anything that isn't.

The legal standard is actual knowledge, not a duty to investigate. You're not required to hire a plumber or open up walls to find problems you don't already know about. But you cannot check "no known defects" on a system you know has one, and you cannot stay deliberately uninformed to avoid having to disclose. A seller who willfully or negligently omits a known problem is liable for the buyer's actual damages if it surfaces later — which, with plumbing, it usually does, often at the worst possible time and cost.

The plumbing items that actually show up on the form

A few plumbing-specific items are worth taking seriously rather than skimming past:

• Water heater seismic strapping. California law (Health & Safety Code §19211) requires water heaters to be braced, anchored or strapped to resist falling in an earthquake, and the TDS includes a specific certification that this has been done. It's a five-minute, low-cost fix if it's missing — see our water heater strapping guide for what code actually requires and what it costs to bring an unstrapped unit into compliance before you list.
• Past leaks and water damage, even repaired ones. If you had a slab leak, a burst supply line, or a sewer backup and had it fixed, that history still needs to be disclosed — a repaired problem is not the same as a problem that never happened, and buyers reasonably want to know if a house has a track record. Our guide to slab leak signs, causes and repair covers what buyers' inspectors specifically look for as evidence of a past slab leak, even a well-repaired one.
• Pipe material. Homes built or replumbed in certain eras may still have polybutylene or galvanized steel supply pipe, or, in older homes with cast-iron or Orangeburg sewer laterals, bituminous fiber pipe nearing the end of its service life. None of these automatically require disclosure by name if you don't know the material — but if you do know, or a past inspection or repair told you, that knowledge has to go on the form.
• Anything currently not working. A running toilet, a fixture that doesn't drain right, water pressure that's dropped — the "currently functioning" checkbox is about right now, not just history.

Why a pre-listing plumbing check is worth the cost

Most sellers find out what's wrong with their plumbing the same way buyers do: when the buyer's inspector finds it, mid-escrow, with a deal already in motion and a clock running. At that point you're negotiating a credit or a rushed repair under pressure, and every finding raises the question of whether it should have been on the TDS in the first place. A licensed plumber walking the house before you list — checking the water heater strapping, running a camera through the sewer lateral, noting any signs of past repairs — costs a few hundred dollars and gives you an accurate list to disclose from, instead of guessing. It also lets you decide, on your own timeline, whether to fix something before listing or price it into the sale and disclose it plainly. A sewer camera inspection report in particular is something many buyers now request anyway; having it ready, dated, and in hand often heads off a renegotiation later.

It's also worth checking your homeowners insurance history before you list. Insurers increasingly flag prior water-damage claims or older plumbing at renewal — see how aging plumbing affects insurance renewal — and a buyer's lender may ask about insurability during underwriting, which can stall closing if it comes up as a surprise.

Why disclosure laws exist in the first place

The TDS exists to fix a basic information problem: the seller has lived in the house and knows things about it that no walkthrough will reveal, while the buyer is committing hundreds of thousands of dollars on comparatively little information. Economist Anupam Nanda's research on state property-condition disclosure laws, published in the Journal of Real Estate Finance and Economics, examined why states adopted mandatory "seller tell all" disclosure requirements and found they function as a response to exactly that asymmetry — shifting some of the burden of catching defects from buyer-side inspection alone to seller-side honesty (see the study). In practice, that means a thorough, accurate TDS isn't just paperwork — it's the mechanism the law uses to keep the transaction honest on both sides.

Getting it right

The safest approach for most sellers is the simplest one: disclose everything you know, in plain language, even if it feels like it might scare off a buyer. An accurately disclosed problem is a negotiating point. An undisclosed one that surfaces after closing is a legal claim. If you're not sure what you actually know — because a past repair was done by a previous owner, or you've simply never had the plumbing looked at — a pre-listing assessment from a licensed plumber turns "I'm not sure" into an accurate answer you can put on the form with confidence.

Getting ready to list and want an honest, documented look at your home's plumbing before you fill out the TDS? Request a free quote and a local licensed plumber can check the water heater strapping, camera the sewer line, and give you a clear, written picture of what's actually there.

Keep reading

• Water Heater Lifespan
• Tank vs Tankless Water Heater in California
• Slab Leaks in California
• Trenchless Sewer Repair in California
• California plumbing cost guides