"I've seen setups where even shadows from ceiling fans triggered false alerts—talk about frustrating."
Yeah, shadows from fans or even shifting sunlight through blinds can definitely throw sensors off. Had a similar issue on a recent build. Here's what ended up working well:
First, I adjusted sensor height—placing motion sensors around 6-7 feet up usually cuts down on false triggers from pets or floor-level movement. Second, angled positioning is key; avoid pointing sensors directly at windows or reflective surfaces. Instead, aim them toward areas with consistent lighting and minimal movement from non-human sources.
Lastly, I added a secondary sensor type—like infrared paired with ultrasonic or microwave sensors. This dual-tech approach means both sensors must detect motion before triggering a response, significantly reducing false positives.
A bit more upfront setup, sure, but worth it to avoid those annoying false alarms down the line...
"placing motion sensors around 6-7 feet up usually cuts down on false triggers from pets or floor-level movement."
Yeah, this is spot-on. Had a client whose cat kept setting off their hallway sensor at night—talk about annoyed homeowners. Ended up repositioning the sensors higher and slightly angled away from windows, and it solved most of it. Still, I've found dual-tech sensors are really the way to go if you want to keep things reliable long-term. Costs a bit extra upfront, but saves plenty of headaches later...
"Still, I've found dual-tech sensors are really the way to go if you want to keep things reliable long-term."
Interesting point about dual-tech sensors...but I'm curious, have you noticed any significant difference in energy consumption or battery life compared to standard PIR sensors? I've been thinking about upgrading some of my older sensors, but I'm always a bit cautious about adding more tech that might draw extra power—especially since I'm trying to keep my home's energy footprint as low as possible.
Also, regarding placement height, 6-7 feet definitely seems like the sweet spot for avoiding pets. But has anyone experimented with ceiling-mounted motion sensors instead? I ask because I've heard mixed things—some say they're great for coverage and fewer false alarms, others complain they pick up too much movement from ceiling fans or even shadows from windows. I guess it depends on the sensor type and room layout?
On a related note (since we're talking smart thermostats here), has anyone integrated their thermostat occupancy detection with separate motion sensors around the house? My thermostat claims it learns occupancy patterns on its own, but honestly...it feels pretty hit-or-miss. It'd be nice if there was a reliable way to link external motion data directly into thermostat scheduling. Has anyone successfully set something like this up without turning it into an overly complicated DIY project?
Just thinking out loud here...
I've noticed dual-tech sensors do draw slightly more power than standard PIR sensors, but honestly, the difference hasn't been huge in my experience—maybe a battery swap every 8-10 months instead of once a year. Ceiling-mounted sensors can be tricky; I tried one in my living room and it kept triggering from shadows cast by trees outside. As for thermostat integration, I've had better luck linking external motion sensors via a smart hub rather than relying on the thermostat's built-in occupancy detection...much more accurate overall.
I've had similar issues with ceiling-mounted sensors—shadows and even passing clouds would trigger mine. Ended up moving it to a wall corner, angled slightly downward...problem solved. Agree on external sensors too; built-in occupancy detection always seems a bit hit-or-miss.
