How to actually pick the right wattage for your bathroom heater
I see it all the time. Engineers just guess. They throw a heater into a room without actually looking at the size of the space, and it usually ends in a disaster. In a bathroom, you aren’t trying to heat the air—that just floats away the second you turn on the exhaust fan. You want that instant, cozy warmth hitting your skin. Getting the power right Start with the footprint. If you’re dealing with a tiny powder room (under 4m²), a 400W to 600W shortwave lamp is plenty. If you go any higher, you’ll basically be baking whoever is standing right under the lamp while the corners of the room stay freezing. For those medium bathrooms (4m² to 8m²), you’ll want to bump it up to 800W or 1000W. But here’s the trick for the big master baths—anything over 10m². Don’t just buy one massive, high-wattage monster. That just creates one giant “hot spot.” Instead, use a few smaller lamps spread out. It covers the whole floor and feels much more natural. Why shortwave works We stick with shortwave infrared because it skips the air entirely. It goes straight for the surfaces and your skin. That’s why you feel it the second you flip the switch, even if there’s a draft in the room. We use quartz glass tubes in our lamps to make sure that heat actually gets through to you. The trade-offs Sure, higher wattage means you’re warm instantly. But it’s a heavy lift for your electrical system. If you hook up three 1200W lamps to one cheap circuit, you’re going to trip the breaker. It’s a pain. You have to check your wiring before you go overboard with the power. On the flip side, lower-wattage lamps tend to last longer since they aren’t working as hard, but they can feel a bit sluggish when January hits. My advice? Go for a mid-range lamp and pair it with a motion sensor or a timer. There’s no point in paying to heat an empty room.