Can I install a window AC unit in the window next to my front door?

Mounting a window unit right next to a heavy door is usally asking for trouble, especially if that door gets slammed or caught in the wind. The constant vibration from the compressor is one thing, but the mechanical shock of a door closing can eventually fatigue the window frame or even pop the glass if the unit isn't perfectly isolated. Most of those small side-lite windows aren't built to hold sixty pounds of dead weight, and the framing is often just decorative trim rather than a structural stud. If youu2019re set on using that spot, you absolutely cannot rely on the window sash or the sill to hold the weight. You woud need to build a **cantilevered bracket** or a dedicated stand that sits on your deck. If you build a frame on the deck that supports the AC from the bottom, you're basially just using the window as a hole in the wall. This takes the weight off the glass and the door frame entirely. Just make sure the stand isn't physically bolted to the door frame, or youu2019ll still get all that vibration rattling the house every time the compressor kicks on. A **dual-hose portable AC** is a much more reliable call for this layout. You can buy or DIY a plastic or plywood insert for that sliding patio door. You just open the door a few inches, slot the exhaust panel in, and you're done. It doesn't block your view as much and thereu2019s zero risk of the unit falling out or shattering a window. Just avoid the single-hose portables if itu2019s hitting 28 degrees in there; they tend to pull hot air back into the room thru the cracks.

If the vertical window is wide enoughu2014usually at least 15 inchesu2014look into a casement AC. Theyu2019re designed specifically for narrow, tall windows. They cost a bit more than the cheap units at big-box stores, but they're much more secure and won't turn your front entrance into a construction zone. Don't just wedge a standard unit in there and hope for the best; I've seen too many of those end up on the pavement or with a spiderwebbed window.

I never realized those units could actually weigh sixty pounds, that sounds like alot for a tiny window frame. If I try that portable AC idea for the sliding door, how do you keep the door locked? My main worry is someone just sliding the door open and walking in while I'm at work. Is there a specific type of bar or lock I should buy for that? Also, for the deck stand, woud I need to worry about the wood rotting out there or is it fine for just one summer?

For the sliding door security, just grab a 'security bar' or even a cut-to-size wooden dowel to drop in the track. It’s a classic low-tech fix that works and keeps anyone from sliding it open from the outside. Regarding that deck stand, watch out for the drainage. If that unit is dripping right onto the wood, you’re going to have a rotten spot on your deck within two summers. I always suggest attaching a small drain hose to the back of the AC pan and routing it off the edge of the deck. Also, make sure you use pressure-treated lumber for the stand or it'll warp and tilt your unit, wich can mess with the compressor over time.

Check your electrical situation before you get too deep into the bracket build. alot of those front entry areas don't have a dedicated outlet nearby, and running an extension cord for an AC is a massive fire hazard. You don't want to be tripping over a thick cord every time you walk in the house.

Also, if you go the window route, rethink the standard accordion side panels. With the door opening and closing constantly, those cheap plastic bits will rattle loose or gap in no time. Use some rigid foam board and heavy-duty weather stripping to get a seal that won't give out the first time the wind catches the door.

One thing people forget when mounting units near doors is the air seal. Every time that front door slams, it’s going to jostle the foam strips or the weatherstripping around the AC. You'll eventually see gaps where your cold air is leaking out. Use high-density closed-cell foam instead of the cheap stuff in the box; it handles the vibration way better.

Also, if you go with the deck stand, build in a slight 1/4-inch downward pitch toward the yard. If the unit sits perfectly level becasue the stand is too "flat," the condensate will pool in the base pan and eventually spill back into your house or rust the fan motor.