For some, winter means overheated apartments and clanky radiators, but for homeowners it’s more often a struggle to keep an inefficient home cheaply warmed. What many don’t realize is addressing energy loss by decreasing cold air infiltration are often relatively simple fixes with associated costs far lower than continuing to jack up the heat. Improving a home’s overall thermal envelope doesn’t always require renovation, and small changes have far-reaching implications. Here is a look at five problem areas that cause heat loss in colder climates and older homes with some potential solutions to explore.
Can daylight help close more home sales?
It’s a fair question. In the world of commercial real estate, where just about everything can be valued in dollars and cents, even daylight has a price: Commercial real estate space with windows lease for about 20 percent more than space without them.
The value of natural light is a growing factor with today’s home buyer as well. Many home buyers like the idea that a home interior bathed in daylight can help:
Home builders are well‐served to play‐up these widely‐documented health benefits, especially in homes that take maximum design advantage of a sun‐drenched southern facing. Turning “the daylight health factor” into a tangible sales benefit can only help reinforce buyer interest and speed the close.
How about daylight aesthetics? Home builders have several ways to play the sun card at design time. Here are three proven daylight‐loving strategies that you may yield unexpected home‐selling results:
The Double‐Sided Strategy
In 1977 a book titled A Pattern Language was published to wide acclaim. Today this 1,171‐page book stands as a classic in architecture, informing the profession with rules – called patterns – that guide winning residential and commercial design.
One pattern goes like this: “When they have a choice, people will always gravitate to those rooms which have light on both sides, and leave the rooms which are lit only from one side unused and empty.”
In many cases, the idea of rooms with windows on two sides is impossible. But enterprising builders can extend natural light by adding a window to an interior wall when an exterior wall isn’t available.
The Large South Window Strategy
Expansive glass on the south of a home can be an attractive design feature, especially if it integrates overhangs to temporize the excessive heat gain of midday summer exposure. Another technique home builders use to moderate heat gain is to add interior surface mass to the south wall. The extra mass, which may be nothing more than an extra layer of drywall, absorbs excess heat and retains it until the room temperature drops. The absorbed heat is then comfortably released into the room.
The See‐Through Home Strategy
A Pattern Language prescribes rooms with windows on two sides. How about the entire house? Entering a home without an interior see‐through to backyard daylight can be an unsettling, even confining, experience. Homes that allow a view to backyard daylight at the entryway are considered more inviting and welcoming.
Today, residential and commercial architects are taking ever more aggressive steps to capture daylight (daylight harvesting) in the buildings they design. As you plan the next phase of your homebuilding program, consider daylight a bright idea to build with.
Sustainable, or green, is no longer just a buzzword–it’s become an important factor for consumers as they make purchasing decisions. In fact, up to 70% of Americans say they are searching for greener products, according to the Shelton Group. Purchasing decisions regarding housing and home renovations are no exception, as consumers are making more green-conscious choices that impact their living spaces. Learn more about how purchase decisions are being affected by increased awareness of how the built environment affects occupants here.
Buyers are demanding homes that won’t make them sick. This means that builders, who are pushing to make their homes energy efficient and airtight, must be extremely careful about the products and materials they use. It’s the Catch 22 of energy-efficient construction: Well-sealed buildings can trap in toxic chemicals, mold, pollen, and other irritants. It takes a range of building science-based strategies—from proper ventilation and moisture control to radon mitigation and conscientious construction practices–to make sure a home is healthy. Read about some of these strategies here.
A Basement Finishing ℞
You have many weapons to fight moisture damage, from passive exterior applications like house wrap and attic/roof ventilation to active drying solutions like bathroom exhaust fans and even whole house air exchangers.
No builder can guarantee complete moisture protection. The exterior assault from Mother Nature is unstoppable. But the interior battering can be just as ferocious. A family of four generates water vapor from all their activities, including showering, cooking, bathing, washing, etc. It adds up to an estimated 13 gallons each week (after converting the mass of water vapor to an equivalent volume of liquid water).
Because you build a great home, observe code, and make smart choices about best practice, the home’s passive and active drying systems keep moisture-loving mold and mildew safely at bay.
Then, for many builders, there’s the basement.
Your approach to exterior moisture control probably includes a rigid foam board cladding around the exterior. It makes sense for a couple reasons. First, the thin, light, and nearly impervious rigid foam board shields the foundation wall from wintry temperature extremes, when the concrete can act as a gigantic, whole-house thermal break.
The proven high-R properties of extruded polystyrene (XPS) can mitigate the transfer, helping provide an extra measure of household comfort on a cold January evening.
Second, rigid foam board helps backstop the waterproofing compound applied to the concrete. An XPS foam board, for example, is ASTM C272-rated to be 99.7 percent waterproof by volume.
The tricky part isn’t the exterior sub-grade. It’s the interior, especially if the owner has specified a finished basement.
A concrete basement wall is packed with water and will be shedding it for years as water vapor. As one basement finisher observes, “Every basement is susceptible to water … it’s only a matter of time.” If provision isn’t made to account for concrete ‘off-vaporing,’ the drywall and framing stands very little chance from moisture-induced mold, mildew, and/or rot.
A basement wall system should not be constructed the same way as an above-grade wall system. It should be engineered for moisture-prevalent, below-grade conditions. Colder basement walls (structural elements are in direct contact with the ground) should be insulated with non-water sensitive insulation such as rigid insulation or semi rigid insulation to minimize condensation from warmer moist interior air, especially in summer. For an in-depth guide to basement finishing best practice, visit here and review pages 12-14.
Experts say a basement finishing system should offer homeowners:
Traditional paper-faced gypsum board wall systems fall short in meeting all seven. Today more and more homebuilders, home remodelers, and homeowners specify systems like the Owens Corning® Basement Finishing SystemTM. This engineered, basement-friendly finishing solution has proven to deliver the long-term peace of mind contractors and homeowners expect. To learn more, visit here.
In today’s residential marketplace, air sealing has become a fundamental part of the home building equation. As building codes and Home Energy Rating System (HERS) targets have evolved, so too has the need for builders to incorporate air sealing into the build equation.
Of course, not all air leaks are created equal. Knowing where and how to air seal will save you money, time and resources on a job. Recent data from a comprehensive industry study has yielded new insights into the role of air sealing in high performance building that can equate to savings for builders and homeowners.
To identify the joints and openings that have maximum impact when sealed, Owens Corning’s Building Science team conducted a comprehensive 12 month study that recorded and measured where and how air leakage occurs in a typical home.
This extensive research conclusively confirmed that joints associated with the wall cavities, which is where spray polyurethane foam (SPF) is often applied, are not the major sources of air leakage. As a result, it is better understood that insulating and air sealing are two separate building considerations when achieving the goal of high performance.
Using laboratory and real-house measurements, the air infiltration research quantified the leakage quantities and characteristics around 17 of the most critical joints and openings commonly found in a home where air is most likely to enter and escape through vulnerable gaps, cracks and seams.
The researchers used fan pressurization to measure which leaks have the biggest impact on reducing the blower door number. The findings were then grouped into three categories – those areas that provide a significant, moderate and minimal result for the air sealing investment in terms of achieving the best blower door result.
Armed with this new data, building professionals can pair a more targeted air sealing and insulation strategy with product solutions designed to gain a competitive advantage.
For example, Owens Corning’s EnergyComplete® Sealant features a flexible composition designed to expand to easily fill gaps and cracks. As the only foamed-in-place air sealing solution that can be applied pre-drywall to create a durable gasket between all top plates, EnergyComplete® Sealant helps builders meet the new IECC 2012 code requirements.
For more information, visit THE JOURNAL OF LIGHT CONSTRUCTION.
We’ve put together a comprehensive resource guide of materials to help market your ComfortBuilt™ homes.
Making your local marketing program effective and affordable, this guide helps you market your homes every step of the way. While you do what you know best—build comfortable, quality homes—we’ll do our part to move the buyer to action.
See Performance Specification Sheets for Climate Zone requirements of the ComfortBuilt™ Home Program.
From the Ground Floor Up, Owens Corning is Contributing Building Science Expertise to The New American Home 2016
Designed and built by Element Design Build, and presented by the National Association of Home Builders’ (NAHB) Leading Suppliers Council, The New American Home (TNAH) 2016 is a 5,200-square-foot contemporary “Desert Elegance” showplace that will incorporate energy efficiency and sustainability, and offer stunning views of the Las Vegas Strip.
Throughout the TNAH build process, platinum-level sponsor Owens Corning is applying cutting-edge building science to help maximize the home’s energy efficiency and to deliver whole home comfort around the clock.
Using advanced predictive Hygrothermal modeling software, the Building Science Team of Owens Corning, led by Dr. Achilles Karagiozis, customized a climate-specific comfort strategy by normalizing variables, including climate, material properties, construction and boundary conditions. Owens Corning worked with the builder to evaluate risks and benefits associated with using different assemblies at the outset and to preempt problem areas that could impact long-term durability.
Several Owens Corning insulation products are specified in the home’s walls, roof and foundation to provide air sealing, moisture management, and acoustic solutions that improve the overall energy efficiency and comfort performance.
This is the first in a series of NAHB-produced videos about Owens Corning’s participation in the 2016 New American Home. Take a look and listen to what Element, the builder, has to say about working with Owens Corning on this project – and then let us know how we can work with you to help Turn Building Science into Building Genius™.
When you collaborate with Owens Corning to design and build a ComfortBuilt™ Home, we’ll help you optimize costs based on HERS scores in your area. Through our partnership, we’ll help you identify the best return on your investment. Exceeding today’s building standards through maximized performance, ComfortBuilt™ delivers on a promise that buyers will ask for by name, and want to call home for years to come.
Performance Specification Sheets for each Climate Zone here outline the requirements of the ComfortBuilt™ Home Program.
Today’s International Energy Conservation Code (IECC) does more than improve performance. It can help avoid unintended consequences related to poor air quality, premature equipment failure and a less comfortable environment. For builders, this means the chance to reduce callbacks and to leave customers with added benefits beyond the obvious.
According to an article from Residential Energy Services Network (RESNET) programs director Ryan Meres, here are just three ways that the steps you take to comply with up-to-date energy codes can help you do more than just improve energy performance.
Added protection against backdrafting from combustion appliances.
In certain situations, leaky duct systems can cause gas appliances such as water heaters to backdraft—drawing unwanted air down vents and flue pipes. The result can be detrimental or even dangerous to the air quality inside.
Complying with the provisions of the 2015 IECC minimizes the leakage rate and disallows other practices that can contribute to the risk of backdrafting.
Longer life for cooling systems (with fewer allergy symptoms).
When it comes to cooling systems, bigger isn’t always better. Systems that are larger than necessary cycle on and off more than necessary. Not only does that make them less effective at removing humidity, it causes undue wear and tear on the system and can promote the growth of bacteria, viruses and mold that can trigger allergies and respiratory symptoms in occupants.
Current energy codes require new methodologies to determine the appropriate size cooling system, which can result in a longer life for the system, for fewer callbacks and lower homeowner costs.
Less waiting for hot water.
Waiting for hot water isn’t just wasteful, it’s annoying. While not every homeowner faces California’s drought restrictions, millions of cold-climate dwellers endure the daily annoyance of waiting for the water to heat up every time they want to wash their hands or take a shower.
Simply following the current IECC means most hot water pipes will be insulated, turning that daily nuisance into a home that just works the way it should.
For more details on the these and other benefits of the International Conservation Code, read the full article here.
