Green building page
We took our first green building class in 2003, put on by Southface Institute of Atlanta, originators of the Earthcraft program, an early green building program that was a joint venture between Southface and the Greater Atlanta Home Builders Association. We began building green houses in Our approach to green building begins with the building science aspects. Whether we are building a speculative house (customer not identified prior to breaking ground) or a custom home for a particular customer, getting the design details right initially is crucial. Groundbreaking architect Peter Pfeiffer (Barley & Pfeiffer, We own software to do both energy analysis and HVAC sizing (Both Manual J and Manual D). Our energy software package, Energy-10, is particularly useful in doing the initial design and figuring out which techniques are most beneficial. This software does essentially the same analysis that the software the HERS raters use does. Energy-10 is known for its ability to handle passive solar applications as well as the ability to figure out which energy-reduction strategies make the most efficient use of your resources. Energy10 can rank order the best strategies to use as well as tell you those that would never pay back if implemented. Our HVAC software calculates the sizing for the HVAC (Manual J) and also the duct runs (Manual D). We can offer our own independent analysis to the HVAC contractor of the sizing of the unit and the placement of the duct runs. We are the only builder in We offer a consulting relationship for all the green building analysis that we can do for you. It is an hourly rate explained further on the We utilize many different green building techniques. Because we build both spec houses and custom houses and in varying price points, not all these techniques are used on every house, but all of them and more are available to use on any homes we build for you. Crawlspaces and basements: Crawlspaces- We have done several closed crawlspaces (also called sealed crawlspaces and conditioned crawlspaces) both with our own crews and utilizing outside contractors. The purpose of them is to reduce moisture and partially condition the crawlspace. Basements- We have built both poured-wall (crawlspace-type-foundations) and whole basements from Insulated Concrete Forms which are super-insulated. The basements have all been finished off to make conditioned space. The exterior walls of an ICF structure are minimally R-22, which understates the true R value due to lack of credit for airsealing. Framing: We use 2”X 6” exterior walls as well as energy-saving framing techniques such as two-stud corners, ladder-T’s for interior-to-exterior-wall intersections, and other thermal bypass techniques. Airsealing: Extreme care is taken with airsealing because as much of 50% of the eventual heating and cooling load is caused by leaks in the exterior envelope of the house. These leaks, once covered with insulation and drywall, become a permanent part of the house, causing needlessly high heating and cooling bills for the life of the house. Insulation: We use 2X6 exterior walls which allows more insulation and less frequent studs. By using 6” studs, we can put in thicker insulation, starting with R-19. We currently are using blown-in-blanket insulation which achieves R-23 in the side walls. Our ceiling insulation is generally R-55 since a high proportion of the heat loss is vertical. Windows: Windows, no matter how good, are the weak insulation areas in the exterior walls. Even the best windows generally achieve no better insulation values than R-5 whereas the rest of the exterior wall may be achieving R-23. So the amount of glazing in the exterior wall is a balance between the reduction in energy efficiency and the increase in beauty and views desired by most homeowners. Sunshine entering houses through the windows both heat the interior and have the capability of fading textiles. We use high-efficiency windows which achieve the lowest solar heat gain and highest insulation vales available for the price point houses we build. Much work is being done in this area by manufacturers and R-10 windows are now available, though pricy. Heating and Air Conditioning: Fireplace: We utilize an EPA-certified clean-burning (72% efficient) wood fireplace which serves two purposes. First is the beauty of a wood-burning fireplace that homeowners enjoy. The second purpose is as a supplemental heat source. The fireplaces have two sets of blowers; one is to supply heated air to the area around the fireplace; the second set of blowers is connected to the HVAC system so that warm air can be circulated to the rest of the house with the flip of a switch. Water Heater: We use high-efficiency water heaters (.91EF or better). Additionally we have used heat pump water heaters that are used to primarily heat the water with standard less-efficient resistance elements only used sparingly. IAQ (Indoor Air Quality): We have used most of the traditional outside-air-introducing techniques (Aircycler, damper-driven introduction, as well as ERV’s [Energy Recovery Ventilators]) as well as the exhaust-only techniques of constant and intermittent exhaust. The techniques used vary in price dramatically and therefore vary with the price point of the home being built. Based upon the price point of the home you want to build we will make a recommendation. The HealthyBuilt home inspector visits the home on several occasions as the home is being built to verify and test particular subsystems. The output of this process, once the home is complete, is a certification that the home complies with the program and a score is derived. Paperwork is sent in that will enable the homeowner to get a 5% energy deduction from Progress Energy, the local utility provider. All of the techniques thus far are site-independent, meaning that these techniques can be used on any home. The site-dependent strategies are solar, wind, and micro-hydro. We are looking for customers that want us to build houses using these techniques. We’ll build the house and work with your choice of the solar, wind, or water vendor. Some of the green features in Mountain Realty Builders’ homes are contained in the following list. Because we build in several price ranges, not all features are available in every home; which features are in which home is a matter of the agreement between the homeowner and the builder. Mechanical systems All heating and air ducting in conditioned spaces All ducts mastic sealed to prevent air leakage-no more than 5% leaks Heating/cooling system properly sized for efficiency by Manual J Motorized damper introduces outside air to replace stale inside air (or ERV) MERV 9 pleated filters installed on HVAC system Ducting protected from debris and dust during construction High efficiency hot water heater Programmable thermostat High efficiency HVAC system (Min 13SEER and 7.55HSPF) Upgrades available. Exterior-Yard Erosion control plan to prevent washouts Onsite trees protected from damage during construction New/replacement trees added at rate of 12/acre Drought-resistant trees and shrubs indigenous to NC Drought-resistant planting plan given to homeowner Drought-resistant sod provided standard Bait termite system used rather than poisoning soil. Interior Low flow showerheads and faucets standard Dual-flush toilets standard Energy Star dishwasher standard Formaldehyde-free particle board/MDF used for trim throughout whole house Formaldehyde-free particle board/MDF used for closet systems throughout whole house Low/No VOC paints used inside house 100% formaldehyde-free insulation used throughout house Concrete countertops in kitchen EPA-certified 72% efficient wood fireplace with central HVAC option can be used to heat entire house. Exterior Construction Construction waste recycled Framing, insulation package, air intrusion independently verified by an outside 3rd party. Use of Insulated Concrete Forms for basement walls (poured foundation walls) High efficiency Andersen or Peachtree windows with low U values and low SHGC values. Double-paned low-e argon-filled windows. Conditioned crawl space for mold-resistance 2X6 exterior walls with R-19 insulation R-30 batt insulation in the floors R-38 to R-55 blown insulation in the ceiling Radiant barrier sheathing in the attic reduces heat buildup by up to 30 degrees Zero formaldehyde OSB used in subfloor Locally recovered aggregate and sand Window and door flashing installed in addition to air/vapor barrier Window and door gaps foam sealed Door and window sill sealers used in addition to window and door flashing Hardiplank siding and trim with 40 year manufacturer’s limited warranty Extensive air sealing and weatherstripping to minimize air and moisture intrusion. In 2009 we became Department of Energy Builder’s Challenge builders. Builder’s Challenge builders have enhanced access to the work of the DOE national labs like Oak Ridge National Labs and high-powered teams like Building Science and Davis Energy. Through them we have the ability to get early notice of cutting edge energy-saving research which we can then apply to the custom homes of our customers. Most Western North Carolina Green Home builders have not certified anywhere close to twelve homes with the local green agency (Western North Carolina Green Build Council). We do not know of any other Western North Carolina Custom Green Home builders that own their own blower doors. No other Recently we became Certified Green Professionals through the new NAHB (National Association of Home Builders) Green program. As a result, we can now build your green home to either the NAHB standard, the Western North Carolina Green Building Council standard, the Environments for Living program recently reintroduced by Masco Corporation, or the original Earthcraft standard. If you have a particular project in mind that will use enhanced building science techniques, we would love to discuss the project with you.
