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CEA’s Home of the Year Sports “Optionsthat Will Sell”PAGE 20

5 Builders ShareTheir OnlineManagementSuccess StoriesPAGE 24

Reaction to FCC’s Ban ofExclusive MDUCable ContractsPAGE 26

Selecting the RightFTTH ArchitecturePAGE 30

Innovative HousingTechnology Awardsat PCBCPAGE 32

The $8.64 monthly utility bill is here … and it’s realistic. PAGE 14

INSIDE:

Energy,Excuses

ZERO

ZEROEnergy,Excuses

ZERO

ZERO

Missouri builder makes herown home an experiment labfor greener things to come.

by John Vastyan

Gemma McKee-Bartholomew’s new home in the Ozarks has radiant heat

comfort, air conditioning and domestic water heat-sourced from a geothermal

system. More than that, the home is what she calls “a lab,” by which she

has developed a process for incorporating such systems.

“I planned this house for several

years,” McKee-Bartholomew explains.

“Every facet of its construction, with

special attention given to all mechan-

ical components — my specialty —

was thought through deliberately.

It’s essentially a live-in laboratory that was ‘green-build’ from the start, before

‘green’ became iconic as the new Holy Grail in construction that it is today.”

McKee-Bartholomew is a nationally acclaimedgeothermal expert who owns Kimberling City, Mo.-based High Tech Homes Construction, Consulting& Seminars and also owns Air Brokers HVAC LLC.McKee-Bartholomew’s championship of smarter,earth-wise construction has earned her the localmoniker, “Queen of Green.”

McKee-Bartholomew fiddled with plans for anear-zero-energy home design for several years.Her plans finally took shape when she completedthe home she built for herself near Branson, Mo.“When we at last broke ground, there were fewsurprises,” she says. “Today, the home has sur-passed my expectations for energy efficiency, per-formance and comfort. The lab test proved-outnicely, but we’re still looking for ways to improvethe formula. That’s what High Tech Homes is allabout.”

Green from the Ground UpMcKee-Bartholomew is reluctant to ignore any keyfacet of a home’s design. So, she often incorporatesinsulated concrete form (ICF) structural compo-nents to create an air-tight envelope. With her ownBranson home, she opted for superbly insulatedICF for this slab-on-grade project.

Embedded in that concrete, the 3,570 square-

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Energy-SavingFormula

Concoctingan

foot single-level home incorporates about 2,700lineal feet of Watts Radiant’s RadiantPEX under-floor radiant systems in just two heating zones.The great room, office, master bedroom and allbathrooms comprise one zone. The second heatingzone is made up of the dining room, living room,kitchen and guest bedroom. They also needed1,200 lineal feet of Watts Radiant WaterPEX, across-linked polyethylene tubing used for radiant

floor heating, snow melting and potable water.The home was designed to require minimal

maintenance, to maximize the use of renewableresources and for energy efficiency. “These werethe key ideas from the earliest point,” McKee-Bartholomew says. “On them, we hung everydesign, construction and mechanical concept.”

Piling On Energy-Conscious OptionsFor the driveway, McKee-Bartholomew chose a“cultured” cobblestone, which requires no mainte-nance. Similarly, she used gutter helmets to whiskleaves from rooftops and composite decking thatneeds no regular sealing.

McKee-Bartholomew also selected a compos-ite flooring with laminate oak, designed specifical-ly for use over the radiant heat system. She alsoused compact fluorescent lights and low-flow toi-lets throughout the home.

Although McKee-Bartholomew knew herhouse would be an energy miser, McKee installedelectrical sub-meters that measure energy use bythe geothermal and domestic water heating sys-tems. To do this, she uses three of the devices typ-

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ically found in commercial or multi-housing build-ings. Their purpose is to continuously monitor andtrack energy used for specific purposes.

“We expected 10 to 15 percent better effi-ciency, and a whole lot more comfort inside,”McKee-Bartholomew says of her home. “What wegot — with comparable winter conditions — wasan astounding 22 percent greater efficiency withradiant. That’s hard, objective data provided bythe sub-metering of energy use.” She adds, “Withmuch better comfort from the radiant, we can setthermostats at around 68–69 degrees and accom-plish a comfort level greater than the forced-airwhen set at 74–76 degrees.”

Of course, this radiant system was not yetfully in place in time for the home’s first winterseason (2005/2006), but that didn’t seem to mat-ter. “The first winter heating of the home was pro-vided strictly via the 2-ton, ground loop-to-air geosystem that was originally intended for use only asa cooling system,” McKee-Bartholomew explains.

In fact, from August 2006 through July 2007,the home required a net electric use of 1,104 kilowatt-hours. At 9 cents per kilowatt-hour, the11th month period cost McKee-Bartholomew just$99.36 or $8.64 a month.

McKee-Bartholomew’s energy data from lastwinter reveals that, when taking into considerationall the benefits of radiant heating (from an effi-ciency standpoint as well as a comfort and healthperspective) radiant has a rapid payback, whichdispels yet another misconception about theaffordability of these systems, she says.

The Geo-Radiant ConnectionThe geothermal unit McKee-Bartholomew mostrecommends for super energy-efficient combina-tion with radiant heat is ClimateMaster’sTranquility water-to-water heat pump. The “geothermal boiler” is a high-temperature, 4-ton(48,000 BTU) unit that accomplishes this with noelectric heating of the water, giving it a coefficientof performance (COP) 25 percent higher than cur-rent units on the market, she says.

New scroll compressors within the Tranquilityunits make it possible to generate leaving watertemperatures of up to 145°F even at ground loopminimum temperatures.

Until now, many experts in the hydronicindustry, like Bob “Hot Rod” Rohr, have beenreluctant to couple geothermal boilers with radi-ant. Rohr is Phc News magazine’s hydronic colum-nist and is also president of Rogersville, Mo.-basedShow Me Radiant. According to him, prior to theupgraded compressors, geothermal systems wereproducing temperatures typically in the 110-degree to 120-degree range. “With temperaturesabove 140 degrees,” he says, “we can use it for alltypes of radiant heat, many forms of hydronic con-vection and to exchange heat for domestic watersupply — all without need of expensive, addition-al electricity to generate that heat.”

The 3,570-square-foot home uses 2,700 lineal feetof underfloor radiant systems in two heating zones.

HOMETECH GEOTHERMAL

The hydronic system for McKee-Bartholomew’s own home was designed by Rohr todeliver a range of temperatures. “We needed toaccommodate the varying demands of an extensivefloor heat system, one hydro-air coil and domestichot water,” Rohr says. Among the controls wereItalian-made Caleffi three-way thermostatic valves,an air separator, a boiler fill and a backflow pre-venter. Rohr says Caleffi has won a stable followingamong hydronic devotees nationwide.

“And, because Gemma [McKee-Bartholomew]’s system may be altered andtweaked at a later time,” Rohr explains, “we alsoused several three-speed SuperBrute circulatorsfrom Grundfos.” He says that the circulators gavethe home “the flexibility of increasing or reducingflow with the simple flick of a switch.” He adds,“I’m also a real fan of the wet rotor design amongcirculators, using the liquid that’s circulated tolubricate the device.”

McKee-Bartholomew acknowledges that most“geo homes” are coupled with ducted water-to-airgeothermal systems. “Radiant heat delivery offerscomfort without compromise, but it is less expen-sive to provide heating and cooling through a duct-ed system,” she says.

Nevertheless, McKee-Bartholomewinsists, in the long run, such “geo home”designs are worth it. “An ultra-high effi-ciency geothermal system, a straight for-ward design and incredible energy savingsall accelerate payback to the homeowner,”she said. “While many in the residentialconstruction industry will claim the costto install geothermal HVAC systems isprohibitive, I say it’s dirt cheap. And Ihave the data to back that up.”

Water: Clean and UnwastedAccording to some industry estimates, afamily of four wastes 12,000 to 16,000 gal-lons of water per year without recircula-tion (or hundreds of thousands, if not millions, ofwasted gallons per sub-division).

McKee-Bartholomew chose Grundfos’ UP10-16 pump to recirculate domestic water within thehome. The pump is installed above McKee-Bartholomew’s indirect water heater and uses adedicated return line (that’s insulated) to accom-plish the recirculation path.

In the opinion of McKee-Bartholomew,EcoQuest’s Springhouse system has revolutionizedthe industry. Its seven stages of sediment filtrationare augmented with a sequestering agent to treathard water and prevent scale. It then uses a pow-erful UV light to disinfect the water it treats,

instantly killing a host of microorganisms. Inspired by the success of all the mechanical

systems in her home, McKee-Bartholomew nowhopes to take green construction into her region’saffordable housing market.

McKee-Bartholomew is now preparing todevelop a subdivision of small, energy efficienthomes in the 960- to 1,400-square-foot range, withthe goal of providing heat, air conditioning and

domestic hot water production for as little as $12to $15 a month.

“Why should sophisticated, energy-wisehomes be available just to people of greatermeans?” she asks.

John Vastyan is a Manheim, Pa.-based journalistand communications professional whose workfocuses on the plumbing, mechanical, radiantheat and geothermal industries. He can bereached by e-mail at cground@ptd.net.

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A geothermal system is a heat exchanger that tapsthe earth’s abundant energy in the most efficientmeans possible.The system harvests heat directlyfrom the earth, which in North America maintains aconstant temperature of about 50°F to 60°F year-round.This is possible because the earth absorbsabout 48 percent of the sun’s radiant energy.

While air-source heat pumps rely on ambient

air temperatures that can range anywhere from20°F to 120°F, the earth’s constant temperatureprovides a much more favorable source for “geo-exchange” heating and cooling.

A modern geothermal system harvests heatfrom the earth through a liquid transfer medium,such as groundwater or an earth-friendlyantifreeze solution. Typically, in a “closed loop”system, fluid flows through an extensive networkof underground tubing. The fluid then flows into

a heat pump.The systems use ground water (or the earth

itself) as a source of building heat in the winterand as a place to “sink” or bury that heat in thesummer. The final process of thermal exchangetakes place in mechanical equipment that servesboth heating and cooling needs for homes andcommercial buildings alike.

Depending on the size of the HVAC sys-tem to be installed, a series of holes aredrilled in the earth near the home in whichthe ground loops are installed. Once installedand connected to the components inside thehome, the loops are then filled with a water-glycol or water-methanol solution that ulti-mately transfers temperature from the hometo the earth in the cooling mode, and fromthe earth into the home the heating mode.

According to geothermal expert GemmaMcKee-Bartholomew, installation of a geother-mal home comfort system is becoming simplereach year. Drilling small diameter bore holes,or excavating ground to insert PEX loops isn’tvery complicated. Either way, thermal transfer

is achieved.

In the WinterDuring the heating cycle, a geothermal system usesthe earth loop to pull heat from the ground. Itthen distributes the heat through a conventionalforced-air duct system or through radiant heat tub-ing in the floor.

In the SummerIn the cooling mode, a geothermal system condi-tions the air in interior spaces by reversing theprocess of thermal exchange. THB

Geothermal, the Understood System

Drilling small diameter holes or excavating toaccommodate geothermal heating/cooling isn’t verycomplicated, according to Mike Bartholomew.

Upgraded compressors make it easy to couple geothermal boilers with radiant heat, says Bob Rohr of Show Me Radiant.