Read the guide: Why does my house shake at night?
How to log vibration in your house
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Step 1: Pick the room where you feel the shaking most. Choose a spot on a hard floor (tile, wood or concrete, not a rug), away from walking paths, pets, the fridge and the washer.
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Step 2: Plug your phone in. Turn off Low Power Mode or battery saver, and set the screen to stay on for the night (on iPhone: Settings, Display & Brightness, Auto-Lock, Never).
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Step 3: Open this page, lay the phone flat with the screen up, and leave the threshold on Noticeable for the first night.
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Step 4: Tap "Start logging". On iPhone, tap Allow when Safari asks for Motion & Orientation access. Then step away and don't touch the phone.
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Step 5: Keep this page open in front. If you switch apps or the screen locks, the browser pauses the sensor and nothing is logged until you come back.
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Step 6: Write down when you feel shaking and what was running at the time: furnace, AC, washer, a truck outside. Your notes are what turn the log into an answer.
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Step 7: In the morning, stop the log and look for clusters on the timeline. Tap "Download CSV" or "Download PDF report" to keep a copy.
What your result means
Your result lands on one of four levels. This page uses the people and buildings scale, which is based on peak velocity in millimeters per second (mm/s).
| Level | Range (peak velocity) | What to do |
|---|---|---|
| Barely noticeable | Under 0.25 mm/s under 0.010 in/s | Not logged at the default threshold. This is normal background in almost every home: distant traffic, wind and your own appliances. |
| Noticeable | 0.25 to 1.0 mm/s 0.010 to 0.039 in/s | You may feel this when you're lying or sitting still, especially at night. It's common near busy roads and in homes with shared floors or walls. Log a few nights to find the pattern. |
| Strong | 1.0 to 2.5 mm/s 0.039 to 0.098 in/s | Most people feel this, and loose things can rattle. If it keeps coming back, find the source, keep the log with your notes, and talk to whoever is responsible for it. |
| Very strong | 2.5 mm/s or more 0.098 in/s or more | Rare inside a home for more than a moment. Find the source soon. If it goes on for long periods, it reaches levels that guidance treats as a concern for fragile and historic buildings, so get it checked if you also see new cracks. |
A house vibration monitor answers the questions you can’t answer by lying awake: when does the shaking happen, how strong is it, and does it follow a pattern? This logger watches the floor for hours and records every event above your threshold, with the time, peak velocity in mm/s, frequency in Hz and how long it lasted. The pattern usually points to the source.
Common causes and fixes
Trucks, buses and trains
These show up as short events of a few seconds at random times, often heavier at rush hour and late at night when freight moves. Potholes, patched trenches, sunken manhole covers and speed bumps near your house make heavy vehicles bounce and hit the road harder. Report road defects to your city or state department of transportation. Fixing the road surface is often the most effective cure. The traffic and train vibration test helps you match events to vehicles.
Your own heating, cooling and pumps
Long events that start and stop on a regular cycle usually come from equipment in or next to your home: the furnace blower, heat pump, AC compressor, or a well, sump or pool pump. Test it by switching one off at the thermostat or breaker and logging again. Common fixes are rubber isolation pads, tightening loose mounting bolts, replacing worn motor mounts, and moving ductwork or an outdoor unit that touches the house frame.
Neighbors
In apartments, condos and townhouses, a neighbor’s washer on spin, treadmill, subwoofer or footsteps travel through shared floors and walls. A washer on spin shows up as a steady event lasting a few minutes, often at roughly 10 to 23 Hz. Share your log politely. Isolation pads under a washer or treadmill often help. The washer floor vibration test and the subwoofer and bass test can confirm the source.
Construction
Events only on weekdays during working hours point to construction nearby. The construction vibration monitor makes a report for that.
Is it vibration or sound?
Many people who describe a low frequency vibration in their house are feeling a low hum, not movement of the floor. Low-frequency sound from engines, compressors or fans can create pressure you feel in your ears and chest while the floor barely moves. If you clearly feel something but the phone logs nothing, the problem may be noise. An acoustic consultant can measure low-frequency sound.
What this tool can’t measure
- Very faint vibration. Every phone sensor has its own noise. Tiny movements can sit below it, so a quiet log doesn’t prove nothing happened.
- Fast vibration. Phones deliver about 60 samples per second, so they measure up to about 30 Hz. The PDF report and the CSV list your phone’s exact limit. Faster vibration from some pumps and compressors can show up as a false lower frequency.
- Sound. The phone measures movement, not noise.
- Other rooms. It only measures the spot where it sits. The middle of a floor and upper stories often move more than a spot near a wall.
- Time while paused. Nothing is logged while the screen is locked or the page is in the background.
- Cause or damage. It can’t say what caused a crack or whether damage happened.
Phone readings are a good guide, not a certified measurement.
Frequently asked questions
Can I leave my phone logging all night?
Yes, as long as it's plugged in and the screen stays on. The page asks the browser to keep the screen awake. If your phone doesn't allow that, set auto-lock to Never for the night and turn the brightness down.
Where is my log saved?
Only in this browser on this phone. Nothing is uploaded. The log survives a page reload, but clearing your browser data deletes it, so download the CSV or PDF report once you have what you need. "Delete all logs" removes everything.
Why does my house shake at night but not during the day?
Night is quieter, and you notice small movements more when you're lying still. Freight trucks and trains also run at night, and heating, cooling and pumps switch on by themselves. Our guide on why your house shakes at night walks through the usual suspects.
What threshold should I use?
Start with Noticeable, the default. If the log fills up with small events from your own household, raise it to Strong. If you clearly feel shaking but nothing gets logged, it may be below what your phone can sense, or it may be sound rather than vibration.
Can I use the report as proof for my landlord or the city?
It's a good guide, not a certified measurement. A clear log with dates, times and peaks is a solid way to start a conversation with a landlord, neighbor or city office. For a formal complaint or a legal dispute, you'll need a survey by a professional vibration consultant.
Last updated .