The complaint is almost always the same shape: one room, or one specific spot inside a room, that runs noticeably colder than the rest of the house, in every season, regardless of what the thermostat says. People describe walking through an invisible line — warm in the hallway, cold three feet later, warm again past the doorway. Pets sometimes avoid the spot. A hand held near the floor or a particular wall feels a draft even with the windows shut.
What separates a routine cold spot from a reportable one is persistence and specificity. A room that's cold because it faces north and gets less sun is not unusual. A room that's cold in July with the AC off, in a house that's otherwise 78 degrees, in a spot that doesn't move when you rearrange the furniture — that's the kind of filing that ends up in this registry.
Start with airflow. Go to the room and check every supply and return vent. A duct that's been closed, blocked by furniture, or crushed behind a wall during a past renovation will starve a room of heated or cooled air and leave it running several degrees off the rest of the house. If you have access to the attic or crawlspace, look for a disconnected flex duct — it's one of the most common causes of a single cold room and one of the easiest to miss because the vent cover itself looks fine.
Next, check what's on the other side of the cold wall or floor. An exterior wall with a gap in the insulation, a room built over an unheated crawlspace or garage, or a slab foundation with no vapor barrier will all read cold to the touch even in a warm house. Uninsulated slabs are notorious for this — the floor can sit 10 to 15 degrees below room temperature and radiate cold upward.
Check the envelope. Run a hand around window frames, exterior doors, electrical outlets on exterior walls, and any attic access hatch or whole-house fan cover. Older houses lose a surprising amount of conditioned air through outlet boxes that were never sealed against the exterior wall cavity. A cheap infrared thermometer, pointed at floor, wall, and ceiling in a grid, will usually show you exactly where the cold is entering rather than just confirming that it's there.
Rule out the obvious last: a window AC unit or mini-split leaking around its seal, a chimney flue damper stuck open and pulling outside air down the flue, or a whole-house fan without a proper insulated cover. Any one of these can produce a cold spot that's real, measurable, and completely explainable.
Some cold spots survive all of it. The vents are open and blowing correctly. There's no crawlspace, slab, or exterior wall nearby — the spot is in the middle of an interior room, sometimes on a wall shared with another heated room. The infrared thermometer shows no draft, no cold air moving, just a patch of air or a section of wall that reads several degrees colder than everything around it and holds that reading whether the HVAC is running or off. Sealing the room doesn't change it. Space heaters warm the air around the spot but the spot itself is slow to follow, or doesn't.
This is the category the registry treats seriously, without treating it as settled. A localized temperature anomaly with no identifiable physical source is one of the more consistently reported and least explainable categories of filing here — not because cold proves anything on its own, but because a filing that has already ruled out ducts, insulation, drafts, and equipment is a different kind of record than one that hasn't. The traditional reading — a specific spot in a house that keeps a temperature the room's own systems can't explain — is old enough that it has its own vocabulary, and this registry doesn't require you to resolve it before recording it.
Take a baseline. Use the same thermometer at the same height, in the cold spot and in a control location elsewhere in the room, morning and night, for three or four days. Note whether the gap changes with the HVAC on versus off, with the door open versus closed, with weather. A duct or draft problem will usually show some variation tied to a cause. A spot that holds a flat, consistent differential regardless of what you change is the more unusual finding, and worth writing down precisely — not just "it's cold in here," but the degree difference, the exact location, the date, and what you'd already ruled out by the time you measured it.
If you're renting or the house is on the market, keep your notes factual and dated. They're useful to you regardless of what's causing the spot, and if you ever want to reference California's disclosure statute or a comparable case, a factual record beats a recollection. Civil Code §1710.2 requires California sellers to disclose a death on the property within the prior three years if asked, or if the fact is material — it doesn't address temperature anomalies, but it's the closest thing state law has to a framework for what a seller owes a buyer about a property's history, and it's worth knowing if you're the one selling later. Separately, and for a different kind of claim, the 1991 New York case Stambovsky v. Ackley, 572 N.Y.S.2d 672, held that a house a seller had publicly and repeatedly described as haunted could be treated, for the narrow purpose of allowing the buyer to rescind the contract, as haunted "as a matter of law" — the court's actual reasoning was about the seller's own public representations creating a duty to disclose, not a ruling on the supernatural itself. This is general information, not legal advice; talk to a real estate or disclosure attorney for anything address-specific.
If a cold spot in your house has outlasted every explanation on the checklist above, search your address in the registry first. Someone in the same house, or a house on the same lot with a shared history, may have already filed something that reads like a piece of the same pattern — a temperature note, a cold-spot filing, an account that names the same room.
If nothing comes up, that's information too. And if you've worked the checklist honestly and the spot is still there, write it down: the room, the measured differential, what you ruled out, and when. The next person who lives in that house won't have your baseline unless you leave it for them. That's what this registry is for.
Yes — trapped moisture and mold growth can make a wall section read colder to touch and to an infrared thermometer, especially near plumbing or an exterior wall. It's worth ruling out with a moisture meter, since it's a health issue independent of what's causing the temperature difference.
Mundane cold spots tied to ducts, insulation gaps, or drafts are fixed to their physical cause and stay put. Reported filings describing a spot that seems to shift, or that multiple people locate in slightly different places within the same room, are less common and worth noting precisely in your own record if it happens to you.
Often, yes — older homes settle, insulation degrades unevenly, and duct systems get modified or damaged over decades of renovations no one fully documented. A house's age is one of the best predictors of a mundane, fixable cold spot, which is exactly why it's worth working the checklist before assuming otherwise.
Check the record for your address — or add what happened, for whoever lives there next.