Added June 20, 2012 By Carrie 65 Comments 
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We survived two miserable Colorado summers without air conditioning before we got the technique of keeping the house cool (somewhat) mastered.  When my cousin lamented on Facebook recently that their house was 82º at 10 AM, I asked if she’d like some tips on keeping it somewhat cool during the day without air conditioning, and before long, my simple list of tips exploded into a 1,100 word+ blog post.Yes, there is a systematic process to keeping your Colorado home from getting hotter than the inside of an oven during the day.  Yeah, you can do this or that for some marginal relief, but if you want to keep the house cool, it’s a multi-step process that must be followed for success.
Keeping the house cool is serious business, people.  Roughly 2/3 of Colorado Springs homes don’t have an air conditioner for reasons I’ll never completely understand.  If you want to install an air conditioner, I say go for it.  We probably will someday, and you’ll probably get your money back when you sell it if you get a few bids and sell it during the summer months (crank up that AC for showings!), says Realtor Kim Guest. Here’s more on the value of an air conditioner when reselling your home.But, if you aren’t in the place to install air conditioning and also aren’t one of those sweet little souls who says “Heat?  Oh, it’s not bad, just turn on a ceiling fan and you’ll be so cool you’ll practically want to wear long sleeves!”, here’s what you need to do:

Go buy box fans for every window in your house.

OK, maybe not every window.  But you’ll want several fans. I think at our peak, we had five for our 3 bedroom house.  They run around $15 or so at Walmart or Target (and can sometimes be found on clearance at the end of summer).

Every day at 5 PM, start monitoring the temperature outside.

You are looking for the outdoor temperature to drop below the inside temperature.  If we’re lucky and get an afternoon thunderstorm, it can cool off pretty quickly.  However, if the storm comes too early in the afternoon, it will sometimes cool off and them warm back up, so watch this.Once it’s cooler outside than it is inside, proceed to the next step:

Pull cold air in and push the hot air out.

You will never get anywhere if all you do is blow the cool air in.  It will feel better temporarily, but you need to get the temperature in your whole house to drop in order to stay cool the next day.Use your box fans in the windows to pull the cold air in (usually you’ll want to pull in from the north windows so you can get the help of any cool breezes) and on the opposite sde of the house, suck the hot air out.  A good cross-breeze is essential to flushing out the hot air of the house and you’ll have to create it artificially since the real breezes are not very regular.

A whole-house (or attic) fan accomplishes this step with very little effort.  We paid about $1,500 to have one installed last year and we loved it, though I’m not going to lie and say it’s the same as having air conditioning.

If you are OK with sleeping with the windows open, you can keep the fans running all night long, pushing the hot air out and pulling the cold air in.  If you go to bed at 8 PM and don’t want to leave the windows open, it’s not going to have nearly the same effect.  But maybe if you go to bed at 8 PM, you get up at 4 AM, which is usually the coolest part of the day anyway and it’s a good time to do the air flush technique.

Cool it off as low as you can get it, and circulate the air.

Oh, you can’t stand to sleep with the temperature below 70º?  Sorry, you’re going to have to deal with it, or deal with a hot house the next day.  Cool off the house as low as it will go (our goal is 65º though that can be difficult if the outside temperature takes awhile to go down), then turn your fan on circulate and run it for awhile to make sure the cooler air is distributed throughout the house.Also – make sure your heater is off if you cool your house down significantly.

Close the windows.

After you’ve cooled it off and circulated the air, close the windows and keep them shut.  You need to keep all that cool air inside, and if you keep windows open, your indoor temperature will rise with the outdoor temperature.Jeremy installed this giant ceiling fan when we were told during our first summer here that a ceiling fan was all we needed to keep cool.  It’s nice to have, but has done nothing to help keep the house feel cool!If you just need air circulation, turn on ceiling fans or use your box fans to blow some air around, but do not open the windows again until the outside temperature is cooling than the inside.

Your house becomes tighter than jail on lockdown the next day.

I’m only partially kidding.  After you’ve gone to the effort cooling off the house, you have to keep it cool, and about the only way to accomplish this is to keep it locked up tight.  I’ll say it again: keep the windows shut, but also the blinds and curtains and doors.  Playing outside may need to be relegated to mid- to late-afternoon.

…but you’ll be cool as a cucumber.

This is not a substitute for air conditioning.  If you are not in Colorado, and are somewhere it’s both hot and humid, you have my sympathy and please go buy yourself an air conditioner at the first opportunity.  If you are in Colorado and have an air conditioner and don’t run it, I am sorry but that is cheap. ;)But, if you live in a place like Colorado where it cools off at night, this simple (haha!) strategy might just help keep you from getting too hot inside this summer.  If we cool off our off to at least 68º, we can often keep it to around 80º inside during the day, which is still hot but is tolerable.Earlier this week, when the highs were in the high 90s and it didn’t cool off much at night, we kept it to around 80º until around 3 PM, and it got up to 84º before we were able to open up the house and cool it off. Thankfully, there are only a couple of weeks a year that get that hot without cooling down much at night, and even then, you can still keep it sort of tolerable for at least a good portion of the day.This is not a pick-and-choose strategy, however – you really do need to follow all of these steps to make it work.  For those of us who get slightly cranky with the heat, it’s worth the effort, though!

Bonus tip!

Oh, and one more tip: run your bathroom fan while you’re taking a shower.  It will suck the hot air out and help you keep the house cooler.  It doesn’t seem like it does much until you compare the difference in steam on the bathroom mirror when you run it versus when you don’t!Do you have a technique for keeping your house cool without an air conditioner?  What’s your secret?