[WGH]

I'm glad my remodel included Marvin Integrity Low E3 windows, a new roof with R40 insulation, high efficiency A/C, and outsulated my block walls with 1" rigid insulation before plastering. Electric bill was $105 last month and it was almost as hot. My house is in the center of the map.

[I.Greyhound Fan]

I don't know but my wife thinks I am hot

[ArthurDent]

Yeah, but don't 'they' all say it's a "dry heat".     Personally I've always thought 'they' were nuts, and not to be trusted. Admittedly any humidity with that would be sauna city, Too hot here, though not as bad as much of the country. Upper 80's to mid 90's for a week now, with another week to go. No rain foreseeable. Invested in a Mitsubishi room heat pump a couple of years ago to supplement the old window A/C I use in the office. Best $ spent in years. As you note about your place Wayne, when I had a new 5/12 roof put on 10 yrs ago the added air space & R-40 insulation made a big difference.

Stay cool Sir. 

[WGH]

..... the added air space & R-40 insulation made a big difference.

I heard a report on the radio recently saying that home owners would be better off starting with the unseen, un-glamorous improvements like better insulation, windows etc. instead of solar panels.

[mresseguie]

I re-insulated our 2nd floor ceiling about 10 years ago to an outrageous R-54. The original blown in insulation was sparse in patches and non-existent over the master bedroom, so I over-compensated.

BYW, Wayne, I love the doors you build. If I could ever persuade my wife    to allow me to buy one, I'd definitely get something. Perhaps someday...

[WGH]

BTW, Wayne, I love the doors you build. If I could ever persuade my wife    to allow me to buy one, I'd definitely get something. Perhaps someday...

Thanks, I ship nationwide. I'm getting ready to take at least a year sabbatical as soon as the sale of my shop closes. Money is in escrow. I plan to build a workshop/studio behind my house with air conditioning.

[nickd]

Insulation is a huge improvement to older homes (mine had none when built in 1956).
Too little attention is paid to reflective barriers however. Keep the heat out of your attic.

Solar panels are like a shade tree over the house lowering attic temps substantially. I had the chance to add reflective barrier when I put on a new roof but it added about $6500.

Huge regret. So I put R40 in the attic, a solar powered vent fan and 5.3kv solar system. The house is easy to keep 70 degrees or lower now and the utility always owes me money.

[JLM]

It's been a hot summer for us (lower Michigan).  Went 5 years without reaching 90F, but hit it dozens of times this year (with high humidity).  And of course being a good doobie signed up this year for a brown out prevention program (they remotely shut off our A/C condenser for 4 hours at a time and pay us $30/year).  First time, the capacitor blew in the condenser and wifey wouldn't let me replace it, so we waited through 3 of the hottest days we've seen for a repairman to charge $280 to replace it, find out the remote shut off wasn't working, and disconnected it.  Thankfully I spend most of my time in the finished basement anyway. 

Our 2005 2200 s.f. home is EPA 5 star certified, so reasonably efficient.  Cost $1100/year to heat, dry clothes, and heat water with propane.  Added 18 PV solar panels 3 years ago over the deck (didn't want holes in the roof or future cost to remove and reinstall after re-roofing).  Not being over the hot roof the panels are slightly more efficient according to installer who remotely tracks performance of all their installations.  Signed up for the tail end of an incentive program so get paid $0.24/kWh for what we generate.  Bottom line, we get paid a net $400/year from the utility versus paying another $1100/year and are on target for 8 year payback.

[macrojack]

My goal is to get rid of natural gas altogether and run everything off my solar panels. Presently, we are spending around $450/yr. on gas (offset by approx. $200/yr. in monthly electric production rebates) and nothing on electricity. Heat source is a circa 1980 Burnham boiler which was oversized before I started my insulation and weatherization journey. It has a standing pilot which I abhor. So replacing the boiler with an electric boiler or a heat pump water heater or a pair of mini split heat pumps is the decision looming. And insulation combined with envelope sealing appears to be my key to success. I believe that the key to making it in The New Would Order will lie in reducing your needs. My focus is on utilities and food as areas where I might be able to withstand the inflation I foresee by keeping my survival as much in my hands as possible. My references to the cause of the problems I dread is deliberately vague. Think what you will but please don't destroy yet another worthwhile thread by making it political.

Getting back to the issue: Did you know that solar has become so inexpensive compared to other measures that some have chosen to buy more panels rather than perform expensive exterior wall insulation projects because the panels are so inexpensive? My own situation won't allow that consideration because, while my cooling loads are small because of extensive exterior shading, my ability to add more panels  is very limited by those same shade trees and my north/south ridgeline. I have 16 panels comprising a 4.32 KW system now and can add perhaps 6 more. Currently producing about 2 MWH more than we use. Need the electric to replace NG for hot water, household heating and cooking. Advice, speculation and experience would all be welcomed. And questions too!

[JLM]

I heard a report on the radio recently saying that home owners would be better off starting with the unseen, un-glamorous improvements like better insulation, windows etc. instead of solar panels.

Yep, always better to seal the holes in the pail rather than trying to continually add more water.  The really cost effective measures are the least glamorous:  chalk, weatherstripping, insulating around electrical boxes/recessed lights on the exterior envelope, and just making sure your attic insulation is well applied (uniformly thick, no gaps, with adequate ventilation). 

Always do a cost analysis before spending serious coin and keep your mind open to alternative ideas.  Lots of new technologies out there but also many crooks that love to take your money.  Some of the ideas from decades ago look pretty silly now.  One of the technologies that is quite efficient but hasn't gotten much press lately is solar hot water (for domestic hot water and space heating).  Watch out for changes in utility reimbursements (our's wants to take away half the net metering reimbursement) and local ordinances (our county recently put a moratorium on wind turbines thanks to a proposal for a large farm of super huge turbines).

[Bizarroterl]

We run the AC as much as we want.  Power bill is $10/month.  Net metering rocks!

[skunark]

Anyone have experience with the newer whole house fans that hang from a rafter and mounts to the ceiling like any air return duct?   

My AC stopped over the weekend and it will be a few days before any repairman can make it out.  This got me thinking about a backup to air conditioning since it does cool off at nights where I live.   I plan to add ceiling fans to bedrooms and family room, but that won’t cool off a house quickly.  It should allow me to raise the thermostat, replace a few inadequate light fixtures and make it more comfortable while sleeping. 

The whole house fan I've used in the past was ceiling mounted and very loud but cooled a cabin in about an hour.   The newer rafter mounted design hints that you can run it all night to lower the thermal energy stored in the house with the end goal of reducing the AC runtime.   So it seems it could be a great backup for the once in a blue moon AC issue and still adding benefit when running the AC. 

[JLM]

Opening and closing the house up on a daily basis actually wastes energy as air conditioning works by first pulling humidity out of the air (which of course provides a sense of comfort) then drops the temperature.  By opening up the house you're allowing higher humidity to be reintroduced, which forces the air conditioning to "start over again" everyday (one step forward, two steps back).

The concept behind whole house fans is valid if you leave it on for a week or longer at a time, but make sure you have plenty of attic ventilation (at peaks and gables) to allow it to be effective.  Air is pulled through any open windows/doors to provide some air movement and perhaps more importantly the attic is also cooled down.  But be sure to seal and insulate the opening before winter. 

A better idea might be a solar powered attic fan that would cool the attic (again check to make sure there's adequate soffit ventilation) without affecting your electric bill.  This is popular down south and quietly helps indirectly to cool the house with or without the air conditioning running.  Cooler attics helps to extend the life of shingles too.

The aerodynamic design of fans hasn't changed in decades.  Newer fans are quieter simply because the bearings are less worn.  Otherwise quieter fans means they're pushing less air. 

[macrojack]

JLM - I want to thank you for your contributions in the household energy savings threads. It is invaluable to me to have a qualified and experienced engineer willing to help explain these issues and provide hints and advice on a subject I have found many an installer does not fully understand. Unlike many people in the news I have nothing but respect for science and what it has brought us.
I'm taking this opportunity to thank you publicly in a selfish hope that you will continue to add clarity and sanity to a topic that has been badly victimized by greed induced misinformation campaigns. Keep up the good work ---- please.

[JLM]

JLM - I want to thank you for your contributions in the household energy savings threads. It is invaluable to me to have a qualified and experienced engineer willing to help explain these issues and provide hints and advice on a subject I have found many an installer does not fully understand. Unlike many people in the news I have nothing but respect for science and what it has brought us.
I'm taking this opportunity to thank you publicly in a selfish hope that you will continue to add clarity and sanity to a topic that has been badly victimized by greed induced misinformation campaigns. Keep up the good work ---- please.

Thanks Tom, but my background is civil/structural engineering.  This stuff comes as a self-interested hobby that has extended for 40 years.  Many focus on the science to the detriment of economics, others do the reverse.  I'm not a geeky guy, so prefer to stick with low tech solutions that make sense and provide the biggest return on investment.

[Escott1377]

Attic fans were (maybe still are?) popular when I lived in Colorado w/ very low humidity.

Leave your windows up at night, pull in the cooler air w/ your attic fan, and then shut the windows during the day.

If there is really any moisture in the air this strategy will not work.

[macrojack]

I live in western Colorado near the Utah border. The temperature for tonight in my area projects to be 82 degrees at 10 P.M., dropping gradually to 69 degrees at 6 A.M. Sunrise and its accompanying reversal of the temp progression occurs just after that at 6:15. The likelihood that your home is already cooler than 82 degrees at 10 P.M. is quite high.
I use the technique you describe during the "shoulder seasons" with great results but it is just too damn hot in a Fruita summer nowadays to invite outdoor air in before the wee hours.

Also feel I should mention having read once (and believed it) that ceiling fans DO NOT cool the room --- they only cool the occupants. I took that to mean shut off the fan when you leave the room.

[JLM]

Also feel I should mention having read once (and believed it) that ceiling fans DO NOT cool the room --- they only cool the occupants. I took that to mean shut off the fan when you leave the room.

Humans sweat, allowing evaporative cooling to occur at the skin if humidity is low enough and there is some sort of wind.  Stagnant air can become 'stale' or 'stuffy', but otherwise, yes, there is little reason to run the fan when the room is unoccupied. 

[skunark]

The aerodynamic design of fans hasn't changed in decades.  Newer fans are quieter simply because the bearings are less worn.  Otherwise quieter fans means they're pushing less air.

The newish (circa 2000) ducted rafter mounted fans are said to be significantly quieter (through the marketing) since it's not directly mounted in the ceiling (circa 1960s), so based on my limited experience and research, it has changed throughout the decades.   Wifi controlled, variable speed controlled, thermal controlled, those were not features on the ones i've used briefly in the past.   I've been looking at the attic fans as well and would want to pair one with the whole house fan to help increase the attic ventilation.   

Where I live humidity is not a factor, it's very likely when you wake up the air outside is significantly more comfortable than the conditioned air within the house, but when it's hot it's hot.   If I lived two hours west or two hours east then I would probably be worried about humidity in the summer.  Humidity is something I closely monitor and more worried about it in the winter months for being too dry than the summer months.

It would nice to have all of these features integrated in a computerized thermostat, maybe call them a smart thermostat, just kidding.   I read that ecobee smart thermostats can control the directions of big ass fans based on if it's heading or cooling.  Interesting their site says the direction of ceiling fans doesn't matter, so i'm baffled on that integration.    Automatic blinds, automatic registers, ceiling fans, exhaust fans, weather should all be integrated and in my neck of the woods, definitely automate a way to help bring in fresh air.

[JLM]

20+ years ago we put a well insulated (6 inch stud wall with fiberglass batts, Pella windows, R-50 blown insulation in attic) fellowship/classroom slab on grade addition on the church building and used rigid fiberglass ductwork for heating only (space stayed cool during the Sunday School hour).  With the fiberglass ductwork and the furnace located in a separate room (accessed only from outside) it was near impossible to hear the furnace run.  13 years ago we built a house with lots of flexible lined/insulated ductwork and again you can barely hear the furnace fan.  So yes, removing the fan from the living space and properly ducted can lower noise levels.

In operating rooms it's critical to have lots of ventilation yet to have a quiet environment, so sound attenuating baffles are used.  Equipment isolators are also used in industrial applications where excessive vibrations (of the gear itself and supporting structure) are undesirable.  Variable speed fans and thermostatically control can help if you don't need full speed 24/7, yet the shape of a fan blade hasn't changed in years.

Good idea to couple whole house fan with attic fan, but now you're running/maintaining two fans.  Humidity, high and low, are both factors here for maybe half of the year.  So with my and wifey's allergies we keep the house sealed up, running A/C in the summer and central humidifier/furnace in the winter.  Fortunately our house is well insulated with good windows and passively solar designed (most windows on the south side with overhangs to shade summer sun.  And 3 years ago added PV solar panels, so we net $400/year on electric and propane cost roughly $1100/year in a 2,200 s.f. house with 1,600 s.f. finished basement.  We had a sunny day last January where it was 5F outside, thermostat set to 65F and the furnace didn't run during the day and of course netted money from the solar panels.

Home automation has a ways to go IMO, but I'm a KISS kind of guy.  Not a good idea to draw air into the house via the attic (unfiltered fibers, mold, pests and their urine/feces being drawn in).  We didn't do ceiling fans, although wish we had in the master bedroom as wifey has a noisy little fan blowing on her all night.  Direction of ceiling fans does matter as heat rises in the room.  I can (and do) open/close registers in the basement (closed in summer, open in winter), not too hard to do.  Again with overhangs window treatments are a matter of privacy more than energy efficiency. 

If you're worried about fresh air have a blower door test done (after you've sealed up all the penetrations you can think of).  Even a reasonably well built smaller house still can leak 1,000 cfm (cubic feet per minute) under 15 mph winds (ask macrojack).  On the other hand if you lock up the house for summer vacation and want to turn the A/C off, adding an ERV (energy recovery ventilator) would be a very good idea (versus coming home to a mold forest and a condemned house), but that means running another fan.  The ERV should replace bathroom and kitchen hood exhaust fans.  It uses a special media where exhaust air and outside air streams are passed over it to recover 2/3rd's of the heat/cool and humidity.  Typical ERVs move 100 cfm (building codes now require 15 cfm per person in commercial sorts of buildings).