Many people look forward to selecting paint colors, countertops and appliances when designing their new homes. One other item that they may want to add to the list is how tightly the home is built.
AIR LEAKAGE AND CODE
A typical existing home can be very leaky by today’s standards. The metric used to measure the leakiness of a home is air changes per hour (ACH), often measured at 50 Pascal’s (ACH50). In many existing homes this number can approach or even exceed 10 ACH50. For context, the International Energy Conservation Code (IECC), which sets minimum standards with regards to energy efficient construction, requires all new construction to meet certain air leakage requirements. In the 2009 edition the limit was 7 ACH50 (air changes per hour @ 50 pascals), which was then tightened to 5 ACH in the 2012 edition, and again to 3 ACH50 for the most recent 2015 edition. It is widely accepted throughout the industry that anything less than 5 ACH50 is considered to be a tight home.
CONDUCTING A BLOWER DOOR TEST
To measure a home’s air leakage, we use a tool known as a blower door. To conduct a blower door test, a fan is mounted into a frame of an exterior door, which pulls air out of the house thus lowering the air pressure inside. Because the outdoor air pressure is now higher than the air pressure inside the home, the outdoor air is pulled in through all penetrations, crack and openings in the buildings envelope.
To measure the airflow, a manometer is connected to the fan and includes reference hoses inside and outside of the home that monitor airflow and pressure. The manometer measures airflow at cubic feet per minute reading (CFM) measured at 50 Pascal’s. Using this number and the volume of the home, we can calculate the infiltration or leakage rate.
Formula for calculating the ACH on a house using a blower door:
“Having a blower door test helped validate the quality and energy efficiency we are getting with our new home. With rising energy costs its great piece of mind that any preventable issues with the home were addressed and we will spend less on heating & cooling as a result.”
– New Homeowner, Ballston Lake, NY
THE BENEFITS OF A TIGHTER HOME
The benefits of having an energy efficiency home with little air leakage are great. Here are some advantages:
Lower utility bills
Reduced heating and cooling loads
Improved indoor air quality
Reduce/eliminate moisture problems
SCHEDULE YOUR BLOWER DOOR TEST
If you are a builder or homeowner and are interested in getting a blower door test done on your home, please contact us at 518-377-9410 or email@example.com.
With the Hurricane Harvey devastation in Houston and the impending doom of Hurricane Irma en route, we thought it would be a good idea to revisit a popular publication written by Newport Partners and ARES Consulting for the U.S. Department of Housing & Urban Development on building Safer, Stronger Homes.
Why should I consider improving the way my home is built? Don’t building codes already ensure a home is safe enough? And doesn’t insurance take care of any damage anyway? How much does it cost and what do I get in return? — These are just a few of the questions that come to mind when considering decisions related to upgrading the construction of your new home.
At a very basic level, most people probably will admit that they want to avoid costly forms of damage to their home, personal contents, and harm to human life. Yet there are natural forces all around us that we often ignore or pay little attention to for various reasons. We tend to assume the big events like hurricanes and earthquakes are already taken care of through building codes. As you read through this document, you will find that building codes don’t fully protect you or your home all of the time. Further, they don’t often address damage from smaller events that can prove costly.
The first step to considering improvements during construction, or mitigation as it is often called, is to become an informed builder or consumer. That is the primary goal of this guide.
Here, you will find that it includes answers to important questions which will help consumers, builders, and others become wise decision-makers. It is not about “pushing” disaster mitigation so much as it is about explaining it so that individuals can make sensible decisions.
How to Use This Guide
This mitigation guide allows you to shop for specific disaster mitigation solutions and associated resources. When you consider one mitigation strategy, other related strategies will be brought to your attention for consideration. Often, you will find that the best value comes in a package deal rather than a piecemeal approach. So, please browse this catalogue for items that make sense to you for your particular situation. And, along the way, pay attention to any other considerations associated with a particular mitigation strategy
BUILDERS: If you already have a strong and current building code in your area, you can use this catalogue to design optional upgrades or include quality features in your homes that will differentiate you from other builders. If you are not in an area where the risk of a disaster is high or if there is an older or no building code, you should first look at the section in this report on the basics of good practice to help prevent damage from ground movements, winds, and flooding.
HOMEBUYERS: Use this catalogue to shop for features you want and to compare builder practices.
Air sealing in buildings reduces energy consumption and in multifamily settings it can also reduce the migration of noise and odors. But these same separation walls in multifamily buildings are also important fire rated assemblies which separate the units. In this December 2016 webinar sponsored by US DOE’s Building America research program, the presenters cover the basics of UL fire rated assemblies, explore how energy and fire code requirements can cause conflicts, and describe best practices for air sealing.
Joe Nebbia of Newport Partners was interviewed by the Journal of Light Construction as their content expert in a recent article published in July 2017. “A New Way to Meet the Energy Code” speaks about following the prescriptive code versus a performance pathway to meet the residential energy code standards. Joe is quoted a number of times throughout the article. Read the full article below.
Ever since the Home Energy Rating System (HERS) index was introduced by the Residential Energy Services Network (RESNET), people have been talking about whether builders should be able to use HERS as a way to comply with the building code. In some states, that’s starting to happen. The International Code Council (ICC) voted in 2013 to create an Energy Rating Index (ERI) pathway to code compliance, based on the HERS index. To allow its inclusion in the code, RESNET has also converted the formerly proprietary HERS index to a consensus standard maintained under the open stakeholder procedures of the American National Standards Institute (ANSI).
A permissive option rather than a requirement, the ERI pathway lets builders use a HERS rating to comply with the 2015 International Energy Conservation Code (IECC) if they wish, and so far 10 states have adopted versions of the IECC that include the ERI. If you work in a jurisdiction that has adopted the 2015 edition of the IECC, you can get a new house approved by obtaining a HERS rating that meets the ERI threshold for your climate zone, specified in a table in the code.
For help understanding the options, JLC turned to an expert: Joe Nebbia, a code consultant with Newport Partners, based in Davidsonville, Md. Nebbia, who teaches comprehensive energy-code education sessions for builders, has been participating in a multistate Department of Energy (DOE) study to assess whether education outreach can boost the industry’s compliance levels and improve the performance of houses. Maryland was one of the first states in the nation to adopt the 2015 IECC, and it does offer the ERI pathway to builders. Nebbia walked us through the various options for code compliance under the 2015 IECC, starting with the basic “prescriptive pathway.”
“In Chapter 4 of the residential code,” said Nebbia, “you will see a whole lot of requirements that are basically a checklist. You put in this much insulation or more, you use windows with this rating or better, you use this much efficient lighting—that sort of thing.” If you follow the prescription, you pass.
But if you know what you’re doing—or if you have expert help—you can choose to follow the “simulated performance alternative” pathway to compliance, which has existed in Section 405 of the IECC for many years. To take that pathway, you have to model your proposed building using appropriate software and compare the model of your plan against the model of a “twin home” specced out to comply with all the mandatory requirements and prescriptive measures in the base code. If the model says your proposed building will have energy costs equivalent to (or lower than) the prescriptively compliant baseline house, then your proposal will be approved—but at inspection time, your local inspector will want to verify that you actually built what you drew.
FLEXIBILITY WITHIN LIMITS
The performance pathway offers trade-offs, but only in certain defined areas. Many parts of the prescriptive code are also “mandatory”—meaning that even if you follow the simulated performance alternative, you can’t get out of those requirements. So, for example, Nebbia explained, the band joist of a wood-framed floor system always has to be insulated to the code-required minimum, and air-sealed as specified in the code—that’s mandatory. On the other hand, slab perimeter insulation is prescriptive, but it isn’t mandatory—so if you follow the prescription, you will pass, but if you don’t follow it, you might still pass. Suppose it’s impractical for some reason to install rigid foam insulation on the edge of the slab up to the top of the concrete, as prescribed in the code. With the simulated performance alternative, you may be able to omit the slab edge insulation from your design, as long as the modeling substantiates that your house will perform as well as a baseline house.
The simulated performance alternative is more flexible than the prescriptive pathway, but it is still limited and constrained, Nebbia explained. Ever since the 2009 edition of the IECC, for example, the code has not allowed builders to trade off equipment efficiency against envelope requirements. “So let’s say I plan to install a super-efficient ground source heat pump or something like that,” said Nebbia. “Well, the building that I’m being compared against also gets a super-efficient ground source heat pump. I don’t get any credit.”
THE RATINGS GAME
Enter the ERI. Written into the 2015 IECC, the ERI “was mainly a change that was requested by the larger production builders,” said Nebbia, “because so many of them were already getting an energy rating done on their homes. The goal was to have a path that uses that same energy rating system to show code compliance.”
Like the simulated performance alternative, the ERI pathway does not get a builder off the hook for mandatory items in the code. But it does expand the available trade-offs, said Nebbia, including HVAC: “Unlike section 405, you can use heating, cooling, and water heating—basically any load in the building—and take credit for that efficiency.” There are backstops, though: You can’t go below the minimum insulation requirements from the 2009 IECC.
So far, builders have been slow to take up the ERI option. One reason, said energy rater Gary Boyer of EDGE Energy in Beltsville, Md., is that most advanced builders can already pass code easily using simpler methods. Instead of using advanced software such as REM/Rate to model their buildings (which requires time-consuming data entry), builders can show compliance using the much more rudimentary REScheck app (a free download from the DOE). Another reason, Nebbia suggested, is that the HERS rating thresholds set by the ERI are quite a bit more stringent than the rating a house would earn just by complying with prescriptive code. In the 2018 edition of the energy code, he said, the step up won’t be so sharp.
THE FREEDOM TO BEAT CODE
So far, Gary Boyer said, he has been asked only once to help a builder use the ERI option—for the townhome project shown on page 29, built by developers Jessica Pitts and John Miller of Flywheel Development, based in Washington, D.C. “They built these super-cool modular net-zero row houses,” said Boyer. “The walls were like R-50—it was way over the top. But REScheck was penalizing them because the windows didn’t meet what it wanted. So I had to model it for them with REM/Rate.”
Pitts and Miller described the problem to JLC in a phone call. The building, it turns out, was precertified as a Passive House and designed using the Passive House Planning Package (PHPP) to meet the stringent airtightness and energy-conservation specifications of the Passive House program. Clearly, the building exceeded code.
“But we had a challenge around the Solar Heat Gain Coefficient (SHGC) factor for the windows,” Miller explained. “Our south-facing glass is designed to be oriented in such a way that it does admit light in the winter to help warm the house. That’s what the Passive House Planning Package expected us to do, so we went with that because we needed that solar heat gain in the wintertime for heating. And it was not code compliant because it didn’t meet the minimum SHGC factor for the code.”
In the design, most of the south-facing glass is sheltered under front porch roofs that will block summer sun, but allow low-angle winter sun in—a smart passive-solar technique. But REScheck couldn’t capture that benefit, and the prescriptive pathway in the code wouldn’t allow the trade-off.
Maryland has an industrial and modular building program that regulates plan review and inspections of modular projects, Miller said, and Flywheel is using a modular manufacturer that works directly with a third-party plan reviewer. “They needed to see something in their package that checked the right box, and we couldn’t check that box,” Miller said. “So we needed the REM/Rate model.”
Passive House buildings use far less energy than average code-compliant houses. But you don’t have to be that far beyond code to get value from the ERI compliance pathway. Joe Nebbia said he expects to see more mainstream builders picking up the approach. “It’s not here to save the builder who has no understanding of energy performance and can’t meet the prescriptive code,” Nebbia said. “It is going to be used by a lot of big builders who have a standard product where they know where that HERS rating is going to be coming in, and they know that they can get efficiencies by trading it off, but they are much better than code minimum. It also might be used by builders who are doing a lot of above-code programs like Energy Star, because they know that they’ve got an efficient product, and this just simplifies their code compliance.”
Kitchens are a principal source of some of the most harmful pollutants generated in the home. Kitchen range hoods can mitigate the impact of these pollutants, but range hoods can be ineffective at capturing pollutants and are often not used either because of noise or because occupants are unaware of when ventilation is needed. With funding from the U.S. Department of Energy, Newport Partners, in partnership with Broan-NuTone, will develop and validate a “smart” range hood that senses pollutants and automatically operates to remove the contaminants efficiently. The proposed smart range hood will be quiet (<1 sone), five times more energy efficient than today’s ENERGY STAR® models, and will capture nearly 100% of pollutants.
A smart range hood can improve residential indoor air quality (IAQ), extend the lives of residents, and save billions of dollars in health-related costs annually. By effectively addressing a major indoor pollutant source with a new smart range hood at a target price point competitive with the intermediate market for standard kitchen range hoods, Newport Partners and Broan-NuTone will enable residential building envelopes to be built tighter while still preserving healthy, acceptable IAQ.
On Monday, June 5th, Sam Bowles of Newport Partners spoke at the 2017 NFPA Conference and Expo in Boston, MA. Recently, Newport had completed a study on behalf of NFPA regarding the perceptions of different stakeholder groups in state’s that have mandatory requirements for home fire sprinkler systems. At the conference, Mr. Bowles discussed some of the findings of that study and how these results can be leveraged for other state’s that might be looking to adopt requirements for sprinkler systems in new construction.
The debate on whether or not to adopt code requirements mandating sprinklers has been ongoing across the country for a long time now. In 2006, sprinklers were included in the International Residential Code (IRC) but were added as an optional appendix and in 2008 they became a standard requirement. However, since being included in the IRC, only two states, Maryland and California, have adopted statewide sprinkler requirements. The debate still continues across the nation, with fire protection professionals heavily advocating for sprinkler requirements while being met with pushback from some other stakeholder groups.
What made this study interesting is that nothing like it has been done before. The majority of previous studies related to home fire sprinkler systems looked at the cost impact, but until we had states that had experience without mandatory requirements, we could not look at how some of the more common perceptions that hindered widespread adoption actually played out. Maryland and California both adopted requirements in 2011, so at the time the study was conducted, they had nearly 5 years of experience in living and working with residential sprinkler systems. (Many areas of these states actually had sprinkler requirements long before they became statewide mandates.)
What is the Internet of Things (IoT) and how does this relate to Newport’s LED project? The IoT is the interconnection of any device for communication purposes either wired or wirelessly. Basically the devices would be able to sense or collect data that in turn generates some kind of response to the acquired data. With LED lighting, since LEDs are essentially computer chips that glow, the range of possibilities for the Internet of Things is almost limitless. We need lighting in our buildings so why not take advantage of the abundance of lighting, especially in commercial buildings
“Beyond simple illumination, this “Internet of Buildings” built on top of next-generation lighting systems will forever change the way we interact with the spaces in which we live.
In your kids’ elementary school, biometric sensors will track students’ alertness, subtly shifting spectrum to automatically boost their focus any time it starts to wane.
Around the corner at the grocery store, beacons embedded in connected fixtures will track every movement you (or your mobile phone) make — from produce to dairy — beaming coupons at you along the way.
Even the lights around your home will be intelligent, learning from and responding to the steady stream of data generated by your wearable devices — using light to help de-stress you after a long day or to perk you up on a cold, dark winter morning.
All of these scenarios (and more like them) are just around the corner. Intelligent lighting will be one of the first markets to realize the dream of the Internet of Things — millions (if not billions) of connected devices, silently sensing and acting on our behalf.” Excerpted from techcrunch.com
As you can see there is a lot of buzz about what the Internet of Things can be and how it can help simplify our lives. Though major concern about interconnecting all of the devices is security. Would it be possible to access a network through one of these internet enabled devices?
While still in it’s infancy, we will see how the market accepts and adopts this newer technology.