Hot Upstairs, Cold downstairs.

Posted on Jan 13, 2011
Q: Its 74 upstairs and 68 downstairs and a rent house, what to do ? A: You need to do the same thing you would do if you owned the house, if you can. You’ll need to enlist the cooperation of your landlord to give you permission to do the following upgrades to the home. What’s going on? Heat’s rises, as we all know, but there’s more to it. When air moves, it must get replaced (the whole nature abhors a vacuum thing). In this case the rising air needs get replaced by air from somewhere else. That somewhere else usually the outside. The rising air causes a very slight vacuum and outside air flows into the house via cracks. It’s winter now, so I’d imagine your feet are cold when walking barefoot on the downstairs, where they probably are not when walking barefoot upstairs. This is because the cold air is being sucked in from the outside. So, you’ll need to caulk and weatherstrip. This is called “airsealing” and the point is to make the building tighter. The goal of air sealing in this instance is to minimize the air leaking in on the first floor and escaping on the second as the hot air finds leaks so that it can escape out of the home and go even higher. Here are some places to look: - If it’s a pier and beam house, the crack between the wall and floors. Your floor boards may have cracks in them as well. Caulk all cracks. - Typically, if you can feel a space underneath your kitchen cabinets, up and behind the toe kicks, you’ll feel a draft if it’s really cold out. If you have this space, you’ll need to buy a can or two of foam ($5) an foam that area shut. - On a sunny day, look at the cracks around all your doors. (Side, top, and bottom.) If you see any daylight, you need to fix the weatherstripping. The best weatherstripping to use is called “3/4 inch silicon bulb weatherstripping.” You cut it to length, jam it against a closed doAustin, TX energy auditor.  Image of silicon bulb weatherstrippingor, and screw it in. The bulb has to make contact with the door all along its length when it’s closed. You may also need to change the threshold. All of this is easy to install if you’ve got a good drill. - Make sure any holes in sheet rock are fixed. Especially look under sinks as plumbers are notorius for punching holes in sheet rock to access plumbing, but never fixing them. - Caulk all plumbing penetrations, both under sinks and in bathtubs. Likewise, you’ll want to air seal upstairs as well, to prevent the hot air from escaping. An energy auditor with a blower door can quantify how leaky the home is. Your landlord may also want to engage an energy auditor to perform a “duct blaster” test, which measures how leaky our A/C ducts are. The average home has 20% duct leakage. The downstairs may be cold because it’s not getting all the conditioned air it should. Too much work?  Then you may want to try balancing your ducts, first.  This is a process of closing dampers on A/C registers in rooms that are getting too much heat in the winter, forcing the air through the system and into rooms that aren’t getting enough heat. First, walk around your home room by room and mark down which rooms are hot and which rooms are cold.  For the hot rooms (assuming you do this in winter), close the dampers 50%.  Open the dampers in the cold rooms full throttle.  This may alleviate much of the problem.  If not, tweak it by closing the dampers a little more in the hot rooms, but never close the dampers all the way. The other thing you may find is that rooms that are too hot or too cold have no way for the air to leave the room when the doors are closed.  This typically happens to the master bedroom.  The solution, then is to keep the air circulating by making a path for the air to get sucked back into the return grille, instead of being trapped in a room. The cheap way to make that path is to cut off the bottom of the door to the room that’s too hot or cold.  Measure up an inch from the floor and mark it on the door.  Then, take the door off the hinges and cutoff the bottom of the door at the one inch mark.  Put the door back on the hinges.  That area under the doors should be enough to get the air circulating. The other thing you may want to think about doing is to turn your ceiling fans on at their lowest setting.  Doing so gets the air moving.  You want the air to mix more so the temperature is more evenly dispersed.  You’ll probably want the fans to turn so that they blow up into the ceiling.  This way, you won’t be chilled by the breeze. Let me know what you tried by leaving comments tot he post.  If these things don’t work, I’ll suggest something else. Also, if you or your landlord can qualify for low income assistance and you’re in Austin, talk to Austin Energy about their Weatherization Assistance Program where they’ll perform an energy audit for free and then make the recommended upgrades (more insulation, air sealing, etc.) with no cost to you  or your landlord.