Cooling Off a Hot Room
Parent Q&A
Archived Q&A and Reviews
Baby's Room is Too Hot in Summer
June 2003
While everyone else welcomes the warm summer days, I dread them. Our house in Oakland heats up very quickly on even the mildest warm days (over 70 outside and we're cooking inside). The bedrooms, with west-facing windows, are the hottest in the house. It's bearable during the days as long as the blinds are drawn and fans are running, but I get very concerned when I put my 13-month-old son to bed around 7:00 and shut his door. Even with the windows open and the fan going full blast, his room remains unbearably hot unless I wait until after he falls asleep and then open the door so that a cross breeze can cool things down. Because our house is not large, this means my husband and I have to tip-toe around in the semi-darkness so as not to wake the baby.
Does anyone have any advice on how to cool down a hot room? Right now I have metal blinds and cloth shades on the windows, but I am thinking about getting curtains with ''blockout fabric'' sewn onto it. Does this work at cutting down on heat as well as light? We are renters, so getting central air conditioning is not an option. An in-the-window air conditioner might be possible, but I'm worried about how much this would cost us over the hot months. Can anyone give me an idea of how much energy they use?
Many thanks! Hothouse Flower
In answer to one of your questions, about the in-room air conditioner We have one that we use in the master bedroom when things get hot. It uses 620 watts (it says on the side -- equivalent to 10-60 watt light bulbs), and very effectively cools one large room (but doesn't cool the whole house when the door is left open, even if we leave a fan in the doorway). This was about the smallest model that was available. In terms of money, it does not cost quite as much for us to run the A/C a lot in the summer as it does to run the heater a lot in the winter (comparing very hot months with very cold months). I'm guessing, though, that we run the heater a lot more in the winter than we do the A/C in the summer. Note that the A/C is fairly noisy; if your baby doesn't mind ''white noise'' this may not bother him; otherwise you might want to run it before the baby goes to bed to cool the room, then shut it off. Karen
We have the same problem in one room in our house. When we bought our house there were special honeycombed blinds that helped keep heat out or in depending on the season, and those worked well. However when I went to get one repaired I found out that they are pretty expensive.
When we re-painted the room the blinds no longer went with the room, so I made some heavy duty curtains which are working great. The curtains are three layers 1) a decorative fabric facing into the room 2) the middle is a black cotton duck/light canvas type material that we chose to block out light completely and 3) a white muslin facing outside (any fabric would do, we just chose muslin because it's light weight and white to reflect light away instead of absorbing it).
The curtains are great because they block out the light completely and keep the room dark so my step-son sleeps better, but keeping the light out also helps keep it cool.
If the air is hot outside, I would not only use the curtains but also DO NOT open the windows to let the hot air in. This is a trick I learned when living in Athens and Madrid, two places that get extremely hot. Just open the windows to let the breeze in during the cooler times of day. anon
Try installing an attic fan and insulating your attic. That dropped the temperature significantly in our house. anon
We, too, live in a hot rented Oakland home. It has helped a great deal to put a fan in the window that points *out* during the day. It pulls the warm air out and creates a lot of air circulation. Once the sun goes down we keep the fan in the window and point it inward. We have one of those large square fans and we just prop the window open with it. It really works. Good luck. Molly G
Reading your post made me wonder whether your attic is insulated. Having lived in homes/apartments both with and without insulation, I can tell you it makes a HUGE difference. Really. You might look into the cost of having this done -- or doing it yourselves -- to see how it compares to the cost of air conditioning. Another benefit is that you will reduce heat loss in winter. Jennifer
My husband and I lived in Phoenix for six years and we never had a/c. We had what's called a ''swamp cooler'' or evaporative cooler which is a unit with grass-type pads on four sides of a metal box. Water constantly runs over the grass pads and air is sucked through them by means of a fan into the house. They are considerably cheaper to run when compared to an A/C unit as all the electricity you are using is to run the fan and a small pump to keep the trickle of water running. I have seen small versions of these mounted in a window as an a/c unit would be. Maybe Sears would be able to get you one. Also, I think I actually saw a portable version of this at Costco a few years ago. Elaine
We're big fans of, well, fans. There's a particular type you might be interested in it's got a thermostat and two fans, each of which can be switched between intake and exhaust (I think it's made by Holmes). We use the intake mode when there's shade outside the window and exhaust when the sun is beating down outside the window.
Perhaps using the exhaust mode to pull the hot air from your son's room and cooler air in under the door. You might consider putting a passive air vent into the door to help airflow if this seems to work; an interior door and vent could likely be had for $75.
Good luck! Boiling in Alameda
Dark colors convert light to heat. If your window coverings are anything other than white, facing outward, you're heating up your room with them. Try putting plantation shades outside the window, hanging them from the eaves. If the shades get hot, they'll be giving off the heat outside. Even better, get a whole-house fan. They are $200 and up, but PG&E is giving rebates of $100. A whole-house fan is mounted in your ceiling and draws all the air into the attic. On hot days, the attic can reach around 150 degrees. This heated attic air will get pushed out the attic vents by this fan, and it also draws all the air inside your house into the attic and out. Turn the fan on after the sun goes down and the air temperature falls outside and after you open all your windows. You'll have fresh evening air inside your home in a matter of minutes. The fan is sized to fit conveniently between the wood framing of your ceiling and is covered by a louvered vent that automatically opens when the fan is on and closes when it is off. Make sure you choose a fan that's on PG&E's approved list at http//www.pge.com kim
Depending on how your house is set up you could put trees in a pot outside his window, to block the sun. I would put a white noise maker in his room, to block out outside noise, although a fan in his room should work. And any blinds that block the sun would keep the room cooler. Kean
You may want to consider an awning or shutters. Also, I just had some work done on my home and the contractor strongly suggested that we install several additional vents on our roof as they will extend the life of the roof and take considerable heat out of our attic and therefore our home. anonymous
We live in a south and west facing Victorian, so I know what you mean about oven-hot rooms! Better window coverings will help some. We like 2- or 3-cell honeycomb shades, particularly for double hung windows because they fit right inside the frame. (We get them from Smith + Noble.) Thermal curtains or shades should also work.
Your second line of defense is to shade the west wall. You don't say if this is a one or two-story house. If it is one story, try growing something up the side of the house to shade it --an espaliered shrub or vine, if there is room, or even just beans gown on strings (this can be done in six inches of dirt, but you'll have to replant to make sure you have coverage for the fall hot season). If its two stories, you might try shading the window and as much of the wall as is feasible with an awning, or, if the landlord is willing to defray the cost, a really tall trellis or arbor (lots of vines will happily grow that tall in our climate!). Even a bamboo shade on the outside of the windows will reduce the heat gain if you can work out a reasonable way to let them up/down. Get 'em big, and use them to cover as much of the wall as seems feasible.
Lastly, consider putting the baby down an hour later, and really working on the cross-ventilation between 7 and 8 PM. You can buy an in-the-window extractor fan and experiment with the best location for evacuating the hot air as quickly as possible. Good luck! Chris
Do you have a second floor where you can open up windows? The hot air will rise and get pulled out, as is what happens with attic fans, which you probably know. Another idea would be to go with the blackout curtains. Last month I sewed some onto my daughter's drapes and love it. I did it mostly to block out light, but it also helps to keep the room cool all day. I am now thinking of installing some into our living room, which absolutely bakes in the afternoon. Sunlight even in one room in the house will heat up the whole house! Enjoying blackout curtains
At our prior house, it came with insulated curtains for our bedroom that faced the hot west sun. The curtains were 3 layers thick and helped keep the room cool during the summer and helped keep the heat in during the winters. The curtains also blocked out the street lamp when we slept. These curtains were custom made. Also, we had a ceiling fan above our bed.
Not all insulated curtains are this thick and efficient. I've seen some in the stores that are rather flimsy (we have some now) and don't help keep the heat in during the winter. Anon
We've recently started using a cold mist humidifier for my son's asthma and I was pleasantly surprised at how much cooler it kept his room during the last hot spell - we also have the 'blackout' blinds and it amazes me how much heat (and light) spills in when we open them. Good luck! amy
Black out shades will make a huge diference. The cheap and easy way is to go to a fabric store and buy the material and just hang them over the windows with thumb tacks. Easy on and easy off. Andrea
We have a house built in 1907 with a southwest facing wall and have the same issue. We have roof and wall insulation but it's minimally effective. We looked into adding additional insulation it would be cost prohibitive. Double pane because of the age and design of the house was $25,000 to 35,000 per window. We had thought about installing a ventilation fan, but getting electricity to the power the fan and the ducting would be cost prohibitive. We thought about installing a gas furnace for the winter, but Berkeley isn't allowing gas appliances to be installed in the city any more.
An electric heather is out of the question for us as PG&E is charging us $.50 kwhr. We estimated it was cost $500 to $1,000 in electricity to heat the two rooms in the winter.
We meet with a guy in Orinda who specializes in passive heating and cooling. He said it could be done but it would very expensive.
We looked into solar. But they want $25,000 and then we would have to buy air conditioners and heaters.
So what do we do? In the summer we open the windows and use fans. In the winter we wear sweaters or don't use the rooms. Far more cost effective to go out for the evening or take a short vacation on the days that are too hot or cold.
Hi! Try Atticare. My family had this problem when we moved into our 1909 bungalow last year. We had Atticare clean out the debris in our attic, install insulation and a whole house fan (turn it on in the evening and it sucks cold air into the house). Our house is only one floor but I would think these steps would work, regardless. They were very professional, provided a consultation and estimate, and were able to schedule within a week. It’s not a cure all—but on really hot days, the house stays cooler longer and cools down faster.
We installed a whole house fanz. It is a great option to cool down a house when nights or mornings are cool. It is a high powered fan that sucks air in from outside and vents it into the attic (which will also cool the air in the attic). We run it on high for about 30 minutes, and it rapidly cools the house.
During the hotter parts of the day, it helps to have blackout curtains for windows with direct sun. Alternately, a mini-split AC unit or wall/window unit can keep a hotter room cool during the day.
The whole house fan is far less expensive than an AC unit. It’s $300-500 for the fan. An electrician or good handyman could install it, if you aren’t comfortable doing it yourself.
We found solar roller shades have helped greatly! Still allow light in but block many rays, cellular shades are another option. Try Smith and Noble, Shade Store, or Budget Blinds depending on your budget. I don’t like curtains but do have to admit hanging linen curtains with a thermal lining has also helped greatly!
Heat rises. So you may have to reduce heat on the first floor to solve this problem. The best solution would be to keep the heat out of the house in the first place. This mean installing blinds or shades on the outside of the house. This can be quite expensive, but effective.
Another way to keep the heat out and the cold in is to open the house at night, and use exhaust fans (maybe you have kitchen and bathroom fans that exhaust to the exterior) to push the hot air out and bring the cold air in. Then close the house up in the morning to preserve the cold air.
Sometimes I cook outside. I plug in the crock pot on the patio so I don't heat up the kitchen.
We have done a couple things to reduce heat on our second floor. First, we had a contractor cut a vent in our attic and install a thermostat-controlled fan. Whenever the attic temperature reaches 100 degrees, the fan automatically turns on and blows the hot air out of the vent. We have definitely noticed a difference on our second floor from this. And it doesn’t even have to be a very hot day for the attic to reach 100 degrees - the fan usually comes on any day the outdoor high reaches 70. The only downside, which is minor, is that the fan makes a low buzzing noise which can be heard on our second floor. But it’s never bothered us, and even during 90 degree heat waves, the fan usually turns off by 10pm anyway.
The other step we took was to have custom blackout shades installed upstairs. They are the accordion style with two layers and some type of insulating layer or material inside. It was pretty expensive as far as window treatments go but we love them and feel it was worth it. We keep them drawn all day on sunny days, then open them and the windows in the evening when it starts to cool off.
One other thing we’re considering for the handful of really unbearable days per year is to get a portable AC unit that is certified for the square footage of our upstairs floor. We would connect it to our bathroom window and place it in the bathroom door facing the hallway, or in the hallway itself if it reaches, then leave the three bedroom doors open. We would also place a tension bar across the top of our stairs and hang a shower curtain to keep the cool air from running down the stairs. We like this solution because we really don’t need central AC - our downstairs stays comfortable even on very hot days, and we don’t want to pay for a central AC unit to be installed or the cost of cooling the entire house for just a few really bad days per year.
Hi there! We also have a 1930s house that didn't have great circulation when we moved in. Two things we've done since that have greatly improved the situation:
1) We had a contractor install a duct & vent connecting our downstairs to our upstairs to allow for better air flow. This helped especially in the winter with bringing the heat upstairs. Not sure of the cost since it was bundled into a larger HVAC project we had done at the time.
2) We installed a whole house fan in our attic (this didn't require any roof modification for us and was quite simple), which is AMAZING and cools the upstairs really quickly on all but the few hottest nights of the year. We did this after 6 or so years of living in our house and can't believe we didn't do it sooner. It cost about $1500 (that was the cost of the fan + labor) and was totally worth it. I believe we just had a handyman type of person complete the work -- not a specialist. (Alternatively, our neighbor just figured it out himself, so it's DIY-able too!)
You may want to consider a "whole house fan." They are a bit intense (somewhat loud) and you have to open windows or doors partway before running (it sucks air from outside in and the hot inside air up and out). But you don't have to run it constantly - in the early evening when it cools down outside is a perfect time to use it. It works really well! I don't know how much they cost to install but I'm sure MUCH less expensive than going the route of air conditioning.
Attic fans are AWESOME. They are especially great in the evening when it's cooler outside than in. With a great WHOOSH, they suck all the stagnant air out of all connecting rooms. They also have a thermometer which turns it on and moves the air in the attic which I guess helps, but that's not as apparent as when you turn it on.
We have found that window fans work much better than ceiling fans or freestanding fans. Since it almost always cools down in the evening, they are affective at bringing the temperature down to a comfortable temperature for sleeping.
The right type of contractor is a "building performance contractor". With a performance contractor step 1 is a audit, then a plan, possibly an application for cost matching, then building. "Eco Performance Builders" in Orinda is one such contractor. The idea is to look at how the whole house works, just apply a standard solution.
Energy Upgrade California can provide some funding.
With so little space in your attic, your best bet may be re-roofing, adding several inches of rigid foam on top of the roof deck. Above the deck the insulation can be unbroken, as there are few obstructions. If you go with a standing seam metal roof, you get solar mounts built in. Standing seam metal costs more up front, but last much longer. Metal roofs also reflect more of the sun's heat, can be installed with a cold roof gap, and solar also provides a lot of shading reducing roof temperature.
Air sealing is the most important thing, more important than insulation in most cases.
Your real problem may come from the lower floors. Get that energy audit to find out.
Attic and whole house fans are tricky, as they can appear to help, but actually raise energy costs. See for example "Green Building Advisor" "All About Attic Venting", or this from Building Science Corporation: https://www.buildingscience.com/documents/digests/bsd-102-understanding-attic-ventilation
See also https://www.efficiencyfirstca.org/
One caution: take a step back before considering wall insulation. On an old stucco house chances are the waterproofing layer between the stucco and the wood is in poor shape.
Insulation in the walls can trap moisture, completely alter the balance of the structure, and lead to rot in a few years. A bad deal.
I kinda went cheap: I use bubble reflective insulation cut to cover the windows that get sun, mostly South and West facing, about $20 for a 2'x10' roll. This keeps the heat out. I also use box fans that I can wedge into my windows in the evening or morning to bring cool air in before I close up the windows. They cost about $20 each.