Kyhayman and a couiple others have asked me about this house so I thought I'd take a minute to summarize how we built an energy efficient home for not that much money. That is to say, a 3,500 sq ft Spanish style all stucco ranch for $375,000. Even if you build smaller, cheaper or bigger, you may pick up some ideas, it never hurts to learn whjat others have tried.After lots of research, we looked at Insulated Concrete Forms (ICF) and Structural Insulated Panels (SIP). Both offer real attractive benefits but are, of course, more expensive up front than traditional stick built homes. We decided to go with stick construction and built the house of 2"x6" walls and a 12" thick roof. We insulated with Icynene in the walls and under the roof sheathing. Notice we did not insulate the attic, but the underside of the roof. The idea is to keep the heat and cold out of the attic. We insulated the concrete basement floor with 2" rigid foam but not the basement walls. Reason: radiant hot water tubing in the basement floor, thus the insulation. However, in the summer the cool walls keep the basement nice. Upstairs floors use Warmboard radiant flooring (hot water). It is like a 1.25" subfloor with channels routed in it for the PEX tubing and alum sheeting to radiate the heat up. Radiant heat is far superior and cheaper than forced air. It doesn't dry everything out, doesn't promote air infiltration, doesn't require furnace filters and justs feels warmer since it warms the floor, the furniture, the walls, etc. You can actually feel the heat 'shining' up from the floor. We love that warm bathroom tile floor on a cold winter morning. There is no forced air furnace. We selected a large (105-gal) Polaris super insulated elec water tank becuse we have lots of kids and the elec coop provided it free. We installed most of a solar hot water heating system too before we ran out of money for the year. We now have two superinsulated 40-gallon hot water storage tanks, a computerized regulator (controls pumps that circulate the heated anti-freeze fromthe collectors through the heat exchangers in the tanks) and 1" copper tubing up from the basement, where the equipment is, to the roof. All we need to install this year is the solar panel themselves and we'll have nearly free hot water. Hot water (for showers, washing machines, etc.) is typically the second largest energy demand in a home, behind HVAC. We put in an 'attic' fan which blows out through an insulated shaft to vents on the roof (since the attic is not vented). So, with the attic fans, ceiling fans in every room and the cooling tubes (more on that in a minute) we can delay running the air conditioner until well into the summer. Good Andersen windows and fiberglass doors keep the wind out. We siliconed every joint and crack before they closed up the walls and ceiling. We put most of our glass on the South for passive solar gain and oriented the house SSE about 10 degrees east of dead south. That shades the south wall in the afternoon but lets the sun in in the morning. Having no windows on the West wall keeps the summer sun out. We hung the roof over about 24" all around the house to shade the windows in the summer but let the sun shine in in the winter when the sun is lower in the sky. With those wide overhangs you can also keep the windows open during mild weather rains without it dripping in. We had the elec coop calculate the HVAC loading exactly based on the sq ft, appliances, occupants, windows, ceiling height, etc. They came up with an AC of 2.5 tons versus the contractor's estimate of 3.5 tons (for a 3,500 sq ft house). Not only do we save money on the AC unit but also on the cost to operate. An oversized AC cycles on and off too much, wasting energy. The name of the game is to run the AC at a steady pace, so don't oversize the unit. Very important to get a computer calculated loading, usually free from your elec utility and, again, don't oversize the AC. We located the AC vents in the ceiling (instead fo the floor) on one side of the room (above the windows) and the return air ducts in the ceiling on the opposite side of the room, so the cool air flows down (instead of trying to push it up), crosses the floor and forces the hot air out the other side of the room. This eliminated stratification where the lower part of the room is cool and the upper part of the room (where the thermostat is) is warm. Thus, again, the AC cycles less. We have no hot spots. When we cleared the land we left trees along the west side to shade the soil and shield us from the harsh afternoon sun. Trees along the north knock down the winter clippers. We cleared a rise on the east in case we ever decide to put in a wind generator. I left wall space in the garage for a wall-mounted solar air heater (a bathroom fan forces air from the garage floor out through the south wall into a black-painted 2"x4"x8' glazed box and back in near the ceiling. I haven't got er done yet but guys that have say it'll run you out of 1,000 sq ft. As it is, without heating it, my three car garage with good windows and south glass stays about 50F all the time during the winter. A garage space heater (propane) heats it up to 70 in about an hour when I want to work out there. About the only really unconventional thing we did was the Earth Cooling Tubes. (See my article on Wikipedia.com). We trenched six cheap 4" plastic sewer pipes 150' from the basement to the hillside in the trees. The trench varies from about 8 feet deep to gradually three feet before exiting. Inside the basement we put a plenum for the tubes to collect in and installed a simple furnace blower (squirrel cage), hypoallergenic filter and ducts to each room. Whatever the temperature outside, the air sucked into the house by the blower is about 60 in the winter and maybe 65-70 in the summer. That's a difference of 20-40 degrees more moderate from the extremes outside. It's like cave air. There's a plastic Tupperware garage wall cabinet I got at Lowes and cored holes in for the tubes to open out into. I cored holes in the cabinet doors and mounted HVAC grills on them to let air in and put a stainless steel washable furnace filter in front of the tube mouths to keep pollen and critters out. The tubes run slightly downhill so as hot summer air enters the cool tubes and condeneses, the moisture runs out the outboard end, providing a little dehumidification, too. So, this morning it was about 30 degrees out. I made bacon and, in a supertight house, that smell would linger for days. I flipped on the cooling tube blower and within an hour the house was all fresh air. The air coming out of the registers in the floor was 62F (I checked) but did not cool the house down since the house itself is heated, not the air (radiant vs. forced air). The old air exhausts out the various baffled openings for bathroom fans, cooktop exhast fan, dryer vent, etc. (No house is truly tight, they all have vents). The rationale is that it is easier to heat or cool air that comes in at 60-70 degrees than air that infiltrates in at 20-100 degrees. Every house needs makeup air to replace what escapes when you run the clothes dryer, the bathroom fans, cooktop exhaust, fireplace or just opening doors. That air will either leak in around your windows, etc. (infiltration) or, if your house is too tight, the fumes, germs odors and chemicals of daily living will stay there and might actually make you sick. The cooling tubes provide managed makeup air by pre-conditioning outside air to earth temperature. Of course, we bought all Energy Star appliances and compact flourescent lights (excepts the one I put on dimmers for mood lighting - ooh la la). Was it worth it? I think clearly so. Our electric bill during the hottest month last year was $180. Our last electric bill was $400+ but I'm also running livestock water tank deicers, pet house heating pads (don't get me started on cats), lights at my front gate and a lot more compressors, power equipment, chargers, etc. than I ran during the summer. Note we have a propane tank for cooking, fireplace starter and garage supplemental heat . We filled the 500 gal tank last July and it still shows 80% full. I learned that when you build your new house you need to spend a few months researching. God bless Google. Get some books on energy efficiant home design. Plan your own house and the technologies you want and try to stick to it. Your builder and his subs will often try to talk you out of things they are not familiar with. They like making houses the way they always make them, its quicker and cheaper for them, even if it ends up costing you more in the long run. Stick to your guns, innovate a little and you'll be glad you did. Your energy costs will be low and your home value will soar in these troubling years to come.
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