Things to aid cooling / avoid heat gain
 

We have a pretty good list of things in our 60+ home energy saving tips. Is there anything else you guys can think of that we can add to the list?

Paint the roof white, but that can be difficult to do.

A longterm investment, but how about planting trees?

You can buy large trees up to 9 years old to get a head start on shade trees.

when I started working mid shift I couldnt keep noise and sun light out of the bed room so I cut foil backed foam insulation. It really keeps the heat out.

When ever I put up or gut one side of an interior wall I insulate it. I like closing doors and closing off A/C to rooms not being used. That helps.

If your heat pump needs replacement, install one significantly smaller than what your HVAC installer recommends. It will be more efficient and last longer if it runs continuously during the hottest days and doesn't keep the house at a constant temperature.

Also, don't install the air handler, or any duct work, in the attic.

HVAC installers always oversize the equipment to avoid callbacks from customers who insist the house stay at 68F in the middle of August. Don't be that customer.

HVAC systems can sometimes be HALF the 500sqft per ton that HVAC contractors typically recommend, especially if kept out of the attic!! If you do install a smaller system it MUST work correctly, and you must get the rated capacity from it. Most systems typically run at about 2/3 rated capacity, which will keep the customer cool if the system is 50% larger than needed....

Window AC's aren't the only ones that benefit from running in the shade, central AC condensers run lower head pressures also. Locate central AC consender on East (will be shaded during afternoon heat) or North side of house if possible. West is the worst side to install AC unit.

Ducts in attic
 

My wife and I insisted on ducts in the attic when we built our home in Alabama. Even knowing the downside to this choice, as in: attic is hotter in summer causing valuable cooled air to be subject to hotter than necessary ductwork, and colder in winter causing colder than necessary ducts.

We chose to put them in the attic so we wouldn't need to dodge floor registers when arranging furniture and would not have floor level dirt going down into our ducts. To help offset this, we put a huge amount {compared to every other house we've seen in our area} of ventilation in our attic and 3 1/2" of opencell foam on the top of the ceiling sheetrock plus 15" of blown in cellulose over the foam.

All this said, the premise of ducts belong under the house is correct. The choice to put them in the attic will result in higher utility bills unless you go to great lengths to mitigate some of the problem you will have created for yourself.

We contacted four HVAC companies to give us an estimate for replacing our old 3 or 3.5 ton central unit and told them up front that we did not have a "rule of thumb" house and described the improvements we'd made. I related I wanted to go with a smaller unit. None of the four HVAC contractors did a "Manual J" test on the house when they prepared a quote. One said we needed 4 tons, two others said the size we had was exactly what we needed. The forth guy just agreed with me that I needed a smaller unit and he'd put a 2.5 ton in for me. Each of the first three mentioned came back and used that "rule of thumb" when they gave me their quotes completely ignoring what I'd said.

That was why I had a home energy audit done on my house and why I felt good in downsizing to a 2 ton variable speed 19 SEER unit. The auditor was the only one that did not have a financial incentive to put in a bigger unit. Plus, I was afraid I'd intimidated the fourth guy into putting in the wrong size unit. Without the audit, we'd have installed a 2.5 ton unit. With the audit, at the audtors suggestion, we upped the cellulose in our attic from 5" to 15" so we could comfortably use the 2 ton unit.

To help deal with the heat without using my air condition (I'm saving it for the really hot weather) I have a box fan placed in the
kitchen window facing in then I open the bathroom window , block the bottom half of it with white cardboard (looks better) so the warmer air is flowed out the top more directly.

Also I close my sunny front curtains and I leave those windows open 1 inch so the positive pressure blows the hot window air out. Actually I leave all the upstairs window open 1 inch, so the house is always venting , I think it makes a difference as well.

In the past I tried placing the box fan in the attic to vent the house, It worked *but* when the fan was off a strong back draft would blow fiberglass particles back into the house. It was nasty , I had to take it down within a few days of installing it or leave it on 24/7 to prevent the back draft.

85F today

I used aluminum kitchen foil for a radiant barrier. The payback for radiant barrier installed is pretty far out, but doing it your self with $30 in foil pays for itself quicker. I did this in the 850 sqft attic of the original part of my house. My friend sprayed lo-mit2 radiant barrier on it 10 yrs ago. The spray ons tend to to reflect only about 80%. During some down time I decided I wanted the air gap/channeling effect you can get with a foil barrier. Already having the spray on I was reluctant to spend a more on store bought barrier so I opted for Reynolds wrap. The trick is getting the heavy duty version and doubling the ends to support staples. I have to temp probes in my attic, one just above my insulation which now hovers about 1 degree above the outside high. The other probe is 2 feet higher, the height of my hvac. It tends to run 5-7 degrees warmer on really hot days. Highest I've seen it was 107f on a 100f day. I have a ridge vent, one gable vent and no soffit or eave vents. It works better than I expected. I feel a lot of it is from the channeling effect of keeping the heat in the rafters going up to the ridge vent.