Parkwood Homes is committed to building a better house every year than we did the year before. One of the areas in which we’ve seen the greatest improvement over the last ten years is Energy Efficiency. High energy costs and climate change concerns have led the industry to an increased focus on building a smarter home. Resulting new technologies and practices have allowed us to build a house that is better for the environment and saves our customers a lot of money.
A Home Energy Rating System (HERS) Score is a measurement of a home’s energy efficiency. Lower scores are better, like golf. The Department of Energy has designated 130 as the score for an average existing home and 100 as the score for a standard new home, while a score of 0 (zero) indicates that the house uses no net purchased energy. Each point lower than 100 represents 1% better energy efficiency than a typical new home. So a house with a HERS Score of 75 would be 25% more efficient than a standard new home with a score of 100.
A new home needed a HERS Score of 85 to be Energy Star certified until 2012, when the standard was raised to the low-70s. Each house has different characteristics that impact its HERS Score potential, but Parkwood’s average scores in Stapleton have always been well ahead of the required standards. We averaged a score of 63 in 2009, and have improved each year to reach an average of 50 on our homes so far this year. That means that a new Parkwood home is about 50% more efficient than a typical new home!
We hope that potential Parkwood homebuyers will compare our HERS Scores and energy savings to re-sales and other builders’ new homes. We’re very confident that the design, care, and features we’ve included in each new Parkwood home will encourage you to step up to a new Parkwood home.
Read below to find out some of the things we’ve done to make every new Parkwood home a model of high performance and energy savings:
Parkwood Homes Top Energy Savers*Because we are always innovating with new products and systems, some of this information may not be current.
Exterior Wall Assemblies – Every new Parkwood home includes 2×6 exterior wall framing (in lieu of 2×4). This provides an additional 2″ thickness in all exterior walls to allow us to add additional insulation. In addition, these exterior walls are designed to limit the amount of wood framing materials wherever structurally feasible (because wood is a relatively poor insulator). The exterior walls are designed with vertical studs every 24″ wherever structurally practical (in lieu of the traditional 16″).
In addition, “Advanced Framing” details are employed throughout these exterior wall designs in an effort to maximize insulation. By paying attention to these details we can maximize the true R-value (efficiency of a home’s insulation) of our exterior walls. For example, rather than using multiple vertical framing studs in the corners of these exterior walls, (which creates thermal bridging by reducing the R-value in this area—wood conducts heat much more than insulation does) we employ design details which retain the required strength but minimize the wood used, allowing for additional insulation.
The next major component of our exterior wall assemblies is the insulation itself. We use a blown-in fiberglass insulation called Owens Corning Pro-Pink. Blown-in insulation, while more expensive than typical “batt and roll” insulation, provides much more even distribution around electrical boxes and eliminates gaps or voids that you see with a batt product. Some builders use a blown-in cellulose product (essentially recycled newspaper). We believe that the Pro-Pink product is superior as it will not absorb moisture, does not support mold growth and will not settle with age.
The last component of our exterior wall assemblies is the exterior sheathing. This is the material that envelops the exterior surface of the framed walls and that the siding is applied over. Most builders are now using a particleboard sheathing (OSB) with some type of house wrap installed as a waterproof membrane on top. We use a product called DOW SIS panels. This product has a combination of three features not normally found in one product:
a. It acts as a structural sheathing, which is required for a properly designed exterior wall assembly.
b. It adds an additional insulating value of R-3 (unlike typical OSB sheathing which has negligible R value).
c. It is engineered with a water resistant barrier on the exterior which, combined with the manufacturer’s adhesive tape at all joints, creates a comprehensive water-resistant barrier below the exterior siding.
This combination of features allows us to construct a wall with a value of R-26. This represents a 100% improvement over a typical R-13 code-built home with 2 x 4 walls, R-13 batt insulation and particleboard sheathing.
Tankless Water Heater – All of our homes feature a tankless gas hot water heater manufactured by Rinnai. These heaters offer significant advantages over a typical tank style water heater installed by most other builders because they heat water only as you use it. On the comfort side, these heaters offer an endless supply of hot water, as opposed to the limited reserve of a tank system. These systems also offer energy savings up to 40% versus some tank type systems and considerably longer life than many tank systems.
NEST Learning Thermostat - The Nest learning THERMOSTAT learns what temperatures you like, turns itself down when you're away and can be controlled from anywhere over Wi-Fi. By programming itself, the Nest THERMOSTAT can save up to 20% on your heating and cooling bill. You just have to teach it well.
Extensive Inspection Process – Each of our customers have an opportunity to inspect their new home with our construction managers at five separate stages during the construction of their home. Our Construction Managers also inspect each new home routinely through the construction period. In addition to these inspections, there are a multitude of independent inspections conducted to verify the proper construction of each new Parkwood home.
An independent Energy Rater, certified under the Energy Star program, completes an inspection of each home before it is dry walled. At this inspection, a Thermal Bypass Checklist is completed to verify that all of the construction details “behind the walls” meet the Energy Star criteria. In addition, the ductwork for the entire home is pressure-tested to verify that the ducts are properly sealed.
Upon completion of the home construction, these energy raters again inspect each home and verify the proper design and installation of the HVAC (heating, ventilation and air conditioning) system. They also conduct a second Duct Leakage Test and a Blower Door Test, which essentially measures the amount of air infiltration into the home to ensure that it meets all Energy Star criteria. At the conclusion of this testing, the energy raters provide each homeowner with a final report for each new home.
Aside from these independent inspections, the City of Denver conducts at least twenty individual inspections of each home including such items as plumbing, electrical, hvac, fireplace, framing, drywall nail inspection and roofing inspections, just to name a few.
Energy Star Approval of all New Homes - Every new Parkwood Home is Energy Star certified to meet the latest Energy Star guidelines. There is a wealth of information available about the benefits of this independent Energy Star certification on their website: http://www.energystar.gov/index.cfm?c=new_homes.hm_index
Solar Options – Solar Photo-voltaic (PV) systems are available as options for most of our new home sites, and systems can be purchased or leased. Our solar partner, Namaste Solar, offers many different options including no-money-down programs. The best source for information on these options is Ben Griffin at Namaste. Ben can be reached at firstname.lastname@example.org
Low-E Windows – Our windows are obtained from Atrium (http://www.atrium.com/), and are the Series 8100 windows, featuring double-pane Low-E glass. Windows manufactured with Low-E coatings typically cost about 10 to 15 percent more than regular windows, but they reduce energy loss by as much as 30-50%. Here’s a good link talking about the benefits of Low-E windows: http://construction.about.com/od/Chemical-Projects/a/How-To-Choose-The-Best-Type-Of-Window.htm
High Efficiency Furnace – Our standard furnace is manufactured by Lennox and has an energy efficiency rating of 92.5% and is Energy Star Qualified. Here’s an interesting Consumer Report about furnace efficiency: http://www.consumerreports.org/cro/appliances/heating-cooling-and-air/gas-furnaces-703/efficiency-matters/efficiency-matters.htm