Building Code Resources

Energy Code Blog

By Rob Pickett, Rob Pickett & Associates, LLC.



Movements in Building Codes  (November 2020)

With the “election” season behind us, the regular state business will regain its priority.  Within that renewal will be the question of codes and regulations on life safety and energy conservation.  Code reviews begin with those currently covered by NH legislation.  For home builders and remodelers, that would primarily be the 2015 International Residential Code (for 1&2-family dwellings, including townhouses, a.k.a., “IRC”) with state amendments.

The IRC, written by the International Codes Council (ICC,, is one of many model codes (a.k.a., the I-Codes) published on a 3-year cycle (explained here).   ICC is one of two codes-writing agencies that publish model building codes and standards recognized by NH.  The other is the National Fire Protection Association (NFPA,  NFPA’s Referenced Standards Fact Sheet (for more info) offers a very good summary of how codes and standards relate and are administered.  The codes and standards published by either agency are updated on a regular basis to adjust for new conditions in the building environment as well as to integrate new methods and materials for construction.  Deck safety, fire protection, structural insulated panels, and cross-laminated timber are just a few of the recent updates.

This article looks at the I-Codes and how they correlate to NH’s building codes.  To manage the immense issue of code updates, the ICC breaks the effort into two Groups.  The Group A codes are the Commercial Building (IBC), Fire (IFC), Plumbing-Mechanical-Fuel Gas (PMG, and related sections of the IRC).  Proposals are currently being developed to modify the 2021 editions of those codes for the 2024 editions.  These proposals will be heard at the 2021 Committee Action Hearings, April 11–21, 2021 in Rochester, NY.

Group B includes general and structural sections of the IBC, Existing Buildings (IEBC), Green Construction (IgCC), the Energy Conservation Code (IECC) and remainder of the IRC.  Proposals for these codes will come later, with the 2022 Committee Action Hearings occurring March 27 – April 6, 2022, also in Rochester, NY.

With that long summary as an overview, it is interesting to note that while the national model codes have finalized the 2021 editions and are on their way to the 2024 editions, NH adopted the 2015 I-Codes and NFPA codes and standards (note that the current electrical code is the 2017 NFPA 70, National Electrical Code (NEC) with NH Amendments.

So, what does this mean?  Is NH lagging behind?  The answer is no.  Each edition of I-Codes is built from the previous and the heritage of safe building practices is maintained.  Despite the thousands of code change proposals every cycle, the process weeds out many of them.  And a “thank you” should go to the building code officials who actively participate and vote on those proposals.  They evaluate the changes as to the potential impact/benefit to their roles in their communities.  Overall, advances in life safety will always generate support from this group while the importance or value of other proposals may be sent back to the “drawing board”.

Adopting an older code does not mean that NH homes are deficient or obsolete.  Building officials are open to new and better if there is reasonable substantiation.  One way to demonstrate acceptable enhanced performance of methods and materials of construction is through evaluation reports published by ISO/ANSI accredited organizations (e.g., ICC Evaluation Services,; Underwriters Laboratories,, and others).

One last note for this post:  What happens in one code cycle can be corrected by the next.  An example is that the 2012 IRC had some disconnects when the 2009 energy conservation provisions were incorporated.  Those disconnects were corrected with the 2015 edition.  Generally, the 2018 edition can be viewed as a good code, but that is for another day’s discussion.  And of course, what are we to do with the energy code?


A Look at NH’s Residential Energy Code  (December 2020)

Last month’s article summarized how the model codes continue to evolve.  It is totally up to the individual state and local code authorities to establish which will be adopted, and this is not uniform across the United States.  Relative to energy codes, the Dept. of Energy (DOE) maintains a web site ( which is helpful to design professionals who work beyond their local market.

The DOE map for Residential construction shown below is updated regularly and accurately shows NH’s energy code to be the 2009.

The website also maintains information about compliance for both commercial and residential construction.  For residential, ( It includes the link to the Residential Energy Code Application EC-1 Form (  This is the prescriptive path to compliance, but that means that it is the most conservative.  Using the option of completing the REScheck calculations and submitting them through the Public Utilities Commission (PUC) can produce a compliant design that may be less expensive to build.

Let’s look at that in a bit more detail.  Form EC-1 offers one solution regardless of the design.  Yet design and code professionals know that buildings perform differently based on orientation on the site, footprint, and ratios to living area (e.g., roof to floor, wall to floor, window to floor).  REScheck (and AreaCalc, the associated take-off tool) provide that flexibility.  Either the design professional can certify the REScheck or the builder can complete and submit it for review by the PUC.  This means that the builder has a choice for demonstrating compliance with the NH Energy Code.

Building beyond compliance with the energy code is also an option.  Our Association has had a long term relationship with NH Utilities and NHSaves (  It was also one of the first states to establish a BuildGreen Council based on the National Green Building Standard (NGBS) Certified Homes program (

NHSaves is an excellent program that provides incentives.  Based on DOE’s ENERGY STAR programs (including Indoor airPLUS, WaterSense, DOE Zero Energy Ready Home and Renewable Energy Ready Homes), homes that are built or remodeled in compliance with the program requirements can receive significant rebates while performing at a rate that saves money by reducing energy demand.  The benefits may extend to resale when lower utility cost shows up in the real estate data.  The only downside is that the programs have been updated and have requirements that are beyond those minimum requirements of the NH Energy Code.

The NGBS is another above-code program managed by Home Innovations Research Center, formerly the National Association of Home Builders Research Center.  A fully accredited third-party inspection program, it is based on ICC 700 National Green Building Standard which includes sections on site development, material resources, energy conservation, indoor air quality, water conservation, and owner/occupant education.  Certification levels reflect attention to design, products, and systems.  Builders of green certified homes have managed to minimize costs when working toward Bronze and Silver levels.  Owner/occupants generally agree that the benefits outweigh the cost of certification and overwhelmingly say they would purchase another green home (see survey report here).

With such a variety of methods for builders and remodelers to satisfy the NH Energy Code, is it true that the issue remains that the minimum requirements are changing faster than education of those implementing them?  Just in NH, the knowledge and experience of builders and authorities having jurisdiction range from none to expert.  We may be able to establish a record of where the median is, but the fact remains that educational opportunities exist.  NH Building Officials Association, state and local NH HBAs, utilities, and others offer them.

The issue is that energy codes themselves do not explain how buildings work.  They set minimum requirements of individual elements and don’t look at the overall building operating in a particular environment.  This is explained pretty well in the article, “Let’s Admit Building Science Is Complicated, Here’s Why”.  It was one of the reasons the Home Builders and Remodelers of Southwest NH (HBRASWNH) developed a three-part educational program with Peter Yost of Building-Wright.  The first presentation was given in person, Fall 2019 to a very receptive audience.  Thanks to COVID, the second session has been continually postponed and now converted to an online event.  It will be a Zoom-conference on January 20 and is open to all NH homebuilders.  For information to attend, please contact or


The Building Thermal Envelope (January 2021)

A look at where the energy codes are heading is such a huge subject that it is tough to break into small bites (bytes?).  Step one is the thermal envelope.

The topic of the 2012 Building Codes was covered in the Fall 2013 issue of Granite State Builder (GSB) by Russ Collins.  He provides examples of code changes to show how they impact the builder and homebuyer.  In the Summer 2014 issue of GSB, I wrote about the need for controlling ventilation considering airtight requirements of the 2012 and 2015 codes.  I wrote again in the Winter issue of 2015 about changes to the ICC’s International Residential Code (IRC).  Then John Starr did an excellent piece in the Summer 2015 GSB issue.

The primary targets of the model building code and the authorities who implement them are life and fire safety —   Protecting those who occupy our built environment.  Life safety covers structural issues, means of egress (including stairs — 2018 IRC = 7-3/4” riser, 10” tread), safety glazing, types of building and how they can be used for various occupancy groups.  This includes requirements for fire protection for protection of both for the occupant and the firefighter, including suppression and more. Our building officials are active in helping to keep the updates reasonable,  necessary, and legitimate.

When it comes to energy conservation codes, is the three-year code cycle bringing more advancements in materials and methods?  In 2018, insulation requirements reached the flat segment of the cost/benefit curve.  Glazing technologies are changing, but other challenges come with them.  The issues of air and moisture movement are the next “opportunity”, driving the call for layers/barriers on the outside of walls.  A change from the 2009 code came in 2012, when moisture control was moved from the IECC to IRC.  This is the type of change that makes code update reviews necessary.

The table below shows how the minimum insulation requirements for the building thermal envelope have changed by code edition.  While NH’s 2009 requirements are not far off the 2021 levels, it appears that going back to a single requirement (one NH climate zone vs. zones 5 and 6) would simplify everyone’s life.  It could mean that NH could adopt the 2018 IECC with Amendments to make the requirements for CZ6 uniform statewide.


Table 1 Building Thermal Envelope by Code Edition


History is important even if often overlooked.  In the early days of energy conservation codes, air leakage was a concern.  Then came the oil embargo and insulation dominated the market even though it was known that 30% of energy consumption was due to the discomfort of a leaky/drafty house.  But insulation is a big market and there is very little money in sealants (e.g., gaskets, tapes, caulking, etc.), so “R” hit the wire (and the codes).

For several years, there has been a movement to help folks weatherize existing homes.  This is the “low-hanging fruit” since it can be effective at a low cost.  Next may be replacement/storm windows, but costs increase. Insulating the thermal envelope (roof, walls, foundation/floor) is more complicated and may affect structures and moisture management.  Even Owens-Corning recognized the impact of air tightness with a study published in 2017 (contact NH HBA for a copy of the pdf).  More information is available in a slide set that can be downloaded at
Like the marginal
benefit of adding more insulation (see, research has demonstrated the diminishing returns of air tightness (graph right).   Here are some other very informative resources on air sealing:

The discussions don’t end with insulation and tightness.  If the building is that tight, here comes the next bite — how good is the air quality contained inside?

Responding to an airtight house requires a ventilation system that addresses all aspects of the house as a system to protect the occupant’s air quality.  Off-gassing from materials used – paints, carpets, cabinetry, etc., to moisture management that minimizes mold/mildew (asthma trigger) to filters and monitors that control contaminants from household cleaners, aerosols, or even outside air pollution.  One method is to balance the volume of exhausted air from bathrooms and kitchen appliances with fresh incoming air.  Another is to build walls to seal off fuel burning appliances to eliminate the movement of carbon monoxide through the home.  This is a 2015 update (read more) in the IECC!

As noted in the previous post, Peter Yost of Building-Wright will be presenting on January 20 part 2 of “Apply Building Science to Achieve Sustainable Building Performance.  His expertise and ability to translate technical information in terms that builders can readily implement covers how buildings work and the impact of product decisions.


A Question of Innovation (February 2021)

Shelter is one of man’s fundamental needs.  It began as a simple structure created from the materials and topography of the building site.  Immigrants to North America used vast woodlands to build log homes across the ever-moving frontier.  On the plains and Southwest, the indigenous materials were sod and adobe.  Bricks and sawn lumber came from Europe until facilities were made to produce them locally. This is our building heritage.

We have evolved since 1680.  The 8/2014 edition of BUILDER Magazine published “Century of Housing”, summarizing change well… “Whether it was war, recession, urban flight, energy shortages, or consumers’ desire for more space, the industry always has provided adaptable, sustainable, and affordable solutions.”  The century (see pdf here) spans from 1920 Sears Catalog Houses to Energy Star and Net Zero Homes.

The authors continue by saying that “Combining historic research with new innovations is what will produce the best housing.”  Design is subjective, but material choices and quality of work is key.  The shift to a carbon neutral environment has started, and the impact of rising temperatures is changing the where and how of building in coastal zones, high wind regions and fire-prone areas.

For those interested in more housing history, look at the timeline from 1930 to present as documented by the U.S. Dept. of Housing & Urban Development (

Throughout this history of change, builders have used new methods and materials of construction.  Yet, there are critics who say the industry “…is rather stodgy, entrenched in an infrastructure of widely disparate players and business models operating at a local level, rigid materials supply chain protocols, and legacy labor skills pinned to outdated building methods…” (January 2019, ProBuilder Magazine article, See Change:  Innovation in Home Building.)  Other critics say that there haven’t been any significant innovations in homebuilding in decades.  Really?

Have you heard that there is an adage that builders don’t like change?  Like any business, a lot of time and effort goes into learning how to run the business and set up a template to maximize success and minimize liabilities.  Anytime a new variable (be it a new product, regulation, or model code) is introduced, there is a natural resistance to the effort and cost required to adjust to it.  Some companies are built to change faster than others.  However, history shows that builders have and do adapt.

History also shows something else… Buyers, real estate markets, supplier networks, and training on new systems and materials are the throttle to innovation in housing.

Building product innovation may be the least intrusive, although builder acceptance may take time.  How fast can the product be proven to perform over the life of the building?  Examples include engineered lumber (e.g., I-joists) and new sheathing products (e.g., Huber’s Advantech and Zip System R-sheathing) that integrate a structural panel with integrated moisture, air, and thermal protection.

Spray foam insulation (SFI) is an example of product innovation that has become widely accepted after learning about its application and quality control points.  Certifying and continuing education has played a big part of the business to improve quality and safety.  A side effect of the added insulation in attics to meet code is the longer duration of roof snow load.  Now the review of the roof structure is tandem to adding insulation.

The level of education available is tremendous with many new products, but it takes some experience sometimes to realize that.  Take I-joists.  Strong and lightweight, builders learned how to use them.  Manufacturers provide engineering guidance for loads, spans and required squash blocking.  But…  Fire forensics revealed that firefighters were injured when the web of I-joists would burn through faster than a solid 2x joist.  The code response was to provide fire protection to the floor assembly using one of various methods (e.g., ½” sheet rock).  As Russ Collins points out (2013 GSB), this appears simple in the code but creates other issues in practice.

Digital technologies driven by changing consumer preferences and expectations have become a key to housing innovation. Look at ZOOM and the work-at-home necessity created by the coronavirus pandemic.  This changed at-home power demand, connectivity, and longer hours of space conditioning.  Will these changes be reflected in new code editions?

The codes transformed lighting with LED technology.  LED lighting has brought about rapid acceptance.  Another technology change that is having a positive impact is heat pump technology as applied to water heaters.

Consumer decisions drive change in homebuilding, but their budgets control where codes do not regulate.  As consumer products change due to their own level of regulation (e.g.,, those innovations are added to the new home or renovation.

The point is that homebuilding and building practices/codes have historically worked hand-in-hand.  New Hampshire homes will continue to change with the times, but homebuilders can rely on their traditions to successfully provide shelter for hundreds of years.


Selecting Methods & Materials (March 2021)

Project specifications list the methods and materials for construction.  These are reflected in details and schedules on the house plans.  Some of specifications are carried from one project to the next.  Structural specs will be custom to each building design and are reviewed as loads need to be continuous from the roof to walls to floors to foundation.  Like the building process, the design of the thermal envelope starts at the foundation and moves up.

  • Foundation – Under slab treatment for radon, moisture, insulation (heated, unheated slab), stem wall, sill plate, termite shield(?).
  • Floor – insulated over unconditioned crawl space, framing inside or on top of stem wall, insulate perimeter to match stem wall.
  • Exterior wall – clear wall definition, wall openings (headers, air and water seal), partition/corner connection, door/windowsill flashing, top of wall to roof/ceiling structure.
  • Roof – Connection/insulation above exterior eave (side) and rake (gable) walls, soffit/ridge vents, heated attic, vapor control above partitions.
  • MEP – how the mechanical, electrical, and plumbing systems interact with the above.

There are several online sources that provide guidance and details for the building thermal envelope.  They are listed in the Resources section of this blog.  Each organization offers similar details to the following from EnergyStar®.

Figure 1 ES floor perimeter detail

Following on the presentation in January by Peter Yost, a large portion of innovation in sealing a home against water and air intrusion has to do with product selection.  Does the product itself provide the answer?  What about installation?  Are contiguous products (e.g., sealants on barriers) compatible?  Is training available from the supplier?

If 30% of energy conservation comes from air sealing, the choices are important.  Selling rated insulation products is the manufacturer’s goal and proponents of these products actively promote higher R-Values.  Sealants are less of a product choice than a process and focus on the builder.  Thus, air sealing may offer greater profits to the builder!  The installers can show quality, build reputation, and earn other benefits from sealing up new homes/remodels.  It is their attention to detail the drives their success.

Beyond specifying insulation and sealing products, today’s energy codes drive the need to focus on air and moisture movement through framing assemblies.  In our climate zones 5 & 6, a vapor barrier is required to keep moisture from moving through wall finishes from the warmer, more humid indoor air.  Kraft-faced batt insulation acts as a vapor barrier, but performance relies on the quality of installation.  Other options are defined in IRC Section R702.7 and vary based on the wall configuration.

Why would condensation occur within a wall that is properly insulated with the appropriate vapor barrier?  Research and case studies have demonstrated the need to understand the passage of indoor vapor through the wall, especially in spaces like kitchens and baths.

From the outside, what happens when the wall is sealed with exterior continuous insulation?  The minimum prescribed wall insulated to R-20 cavity with R-5 continuous insulation allows the dew point occurs within the wall.  Again, IRC Table R702.7.1 provides guidance for use of Class III vapor retarders (latex or enamel paint) to minimize the negative effects of moisture trapped in the wall.

Consumer advocates and Federal agencies maintain minimum product standards that are beyond the building codes.  Their research and development offer innovations and choices for new homes and remodeling projects.  New building products that are not covered in the building codes can be reviewed by accredited agencies that publish evaluation reports.  The product manufacturers make considerable investments in these reports to demonstrate conformance to the code, often including limitations of use.  Builders and code officials can rely on these evaluation reports to determine if an innovative product can achieve the performance its manufacturer claims.

Figure 2 ICC-ES Evaluation Report

Some companies like Dow and Simpson Strong-Tie have incredible commitments to research and development.  These manufacturers have a huge impact on builder decisions and have support staffs who provide assistance.

It is known that building methods and materials can change quickly, which is the “why” for the 3-year code development cycle.  However, the building industry doesn’t change that fast, which is why it balks when new codes are published.  Look at green building… what was abnormal, costly, and impossible in 2007, eased by 2010, and is readily available in 2020.  The question is, when will new editions of the International Energy Conservation Code be as stable as the rest of the IRC?







Model Codes and Regional Variation (April 2021)

Building science experts continually advise to look at a building as a complete model that responds to the environment in which it is created. Consider the whole versus a focus on one element and integrate human comfort in the analysis. This is why green and/or Energy Star certifications pertain to the completed home. A good example of this is documented in the 2005

publication, “Building America Best Practices Series: Volume 3 – Builders and Buyers Handbook for Improving New Home Efficiency, Comfort, and Durability in the Cold and Very Cold Climates.” The coordination of the building science expert (like our friend Peter Yost or your HERS rater) and the builder is depicted in Figure 6 (at the end of this article).  Note that Volume 3 is for cold and very cold climates. Going back to the Climate Zone (CZ) map in the IECC, we see that NH’s CZs 5 & 6 are among the geographic region of the U.S. that is green and blue in Figure 3. Are we to believe that building is homogenous across those areas? Let’s immediately separate New England from the region noted as “Dry”. Face it, they are spoiled there. Untreated wood products exposed to the elements in a dry climate are more durable than in the “Moist” East. A blog by a Colorado company explains why preservative treated decking is bad in the mountain region (‐treated‐wood‐not‐used‐colorado/). The cold, moist climate of the northern and eastern regions of the U.S. are a different story, but sub‐regions exist there too. In the Great Lakes region, lake effect snows can generate larger roof loads and encase homes with snow and ice. In New England, we experience mild summer seasons and harsh, frigid winters. And then there are micro‐climates where terrain alters weather patterns. Even though the climate is different, housing in NH is generally a traditional style. The website identifies New England architectural styles as Colonial, Cape Cod, Georgian, Farmhouse, and Shingle. Mediterranean, Ranch, and Modern styles are identified as western by Craftsman and Prairie styles are popular in the Midwest, but Farmhouse and Shingle styles show up throughout the region. Zillow even published a list by state of the prevalent architectural style (scroll down at‐architecture‐style‐regional‐or‐not‐4388/).


One difference in New England is that comfort from the longer cold weather season drove certain design responses.  For example, wall openings were once limited in size and quantity until better windows came along.  Heating and lighting have been fueled by natural gas since the late 1800s.  Coal and wood fueled home heating.

The chart from in Figure 4 shows a far greater dependence on fossil fuels for home heating in the Northeast than the other regions.

Figure 4 2015 Residential Energy Consumption Survey, updated 7-31-18


The nationalization of news, data, statistics, etc. tend to mislead us when trying to set policy for one state.  Perhaps a regional approach is more appropriate, especially as Net Zero policies drive electricity over use of fossil fuels.  This Winter’s cold blast in Texas may have taught us all something.  First, pay attention to the thermal envelope.  Second, consider a back-up heat source (wood?).  Maybe a third is to rely more on local power generation (renewable or not) to reduce the extent of grid damage in such weather.

Conversions to alternative methods and materials is possible.  One resource for promoting this is the Northeast Energy Efficiency Partnerships (NEEP,  It is one of six Regional Energy Efficiency Organizations (REEOs) formed in 1996.  A non-profit, NEEP is funded, in part, by US Department of Energy to support state efficiency policies and programs.  NEEP’s goal is to assist the Northeast and Mid-Atlantic region to reduce building sector energy consumption at least three percent per year and carbon emission at least 40 percent by 2030 (relative to 2001).  They want to help NH understand how to move to greater reliance on electrification and natural gas.

Furthering the idea of regional responses, perhaps states and counties of similar climate and terrain could publish a regional code or at least “best practices”.  One idea would be a single “Montshire” energy standard for the mountain and lake regions across state and county lines from the Adirondack region of NY to Maine.  It may be that an adjustment for the coast of Maine/NH makes sense.  At least the mountain version could be modeled on the work done in Vermont.  Builders (stakeholders) in the Vermont Building Energy Code (CBEC or RBEC) development process had a significant impact on the result.  Updating the 2018 IECC, the 2020 VT RBEC (residential) is good piece of code development.

The Montshire region is a predominantly heating climate (zones 5-7), has common interests in reducing utility costs, carbon footprint, and housing cost while maintaining a standard for human comfort.  Can a movement away from fuel-burning appliances/equipment be effective?  Or is it ok to consider natural fiber (wood to pellets to biofuels)?

Figure 5 from EIA provides data from a national survey of residential electricity use.  This is data from 2015, so imagine how much it has changed in the past year alone.  The graphic paints a complex picture when responding to issues of electricity generation, distribution, and the demands for thermal comfort.

Figure 5 Estimates of Residential Electricity Use

Figure 6 Coordinating Science and the Building Process

Where is this heading?  An energy code alone cannot address all these areas.  Net Zero/Carbon Zero will still need Energy Star efficiency targets for appliances, lighting, and HVAC.  As our homes become more “intelligent”, how will energy use be managed?  Perhaps it is time to recognize that the ideal target for the building thermal envelope has been defined, and it is time to start adjusting to how occupants use dwellings.

International Code Council

The NHHBA is a member of the International Code Council (ICC).

The mission of the ICC is to promulgate a comprehensive and compatible regulatory system for the built environment, through consistent performance-based regulations that are effective, efficient and meet government, industry and public needs.

To view all the products and services available from the ICC click here.

In 2006 New Hampshire adopted the IRC 2000 as the state-wide residential building code for one and two family dwellings. Since that time the State Building Code (including the Energy Code) has been updated to the 2015 codes. 2015 IRC Update

NHHBA has a copy of the 2015 International Residential Code (IRC) book in a loose leaf binder format available to members for reference.


Building Code Links & Resources

New Hampshire Building Code Review Board (BCRB) – By statute the NHHBA has a seat on the BCRB.

The State Building Code Review Board is charged with the responsibility for reviewing and recommending to the legislature any adoption of codes in New Hampshire.

New Hampshire Building Officials Association  
Attached is a PowerPoint presentation provided by the NH Building Code Officials outlining the significant changes in the 2015 International Residential Code (IRC). Click Here

NAHB’s Construction Codes & Standards on the web.


Is Net‐Zero a Prescriptive Minimum? (May 2021)

The question and motivation for writing is, how can we establish an energy efficiency standard that is good now and in the future? The new ICC Residential Energy
Standard may be the answer. Work is starting towards a 2024 ICC publication that reduces the trauma of 3‐year code development cycles.

Carrying last month’s idea forward, net‐zero needs clarity. Various advocates have offered a response, but a good definition is offered by the Whole Building Design Guide’s

Net Zero Energy Cost is perhaps the simplest metric to use: it means that the building has an energy utility bill of $0 over the course of a year. In some cases,
building owners or operators may take advantage of selling Renewable Energy Credits (RECs) from on‐site
renewable generation.

Ideally, a building thermal envelope should minimize heat loss/gain while systems (air/water conditioning) are extremely efficient and distributed renewable energygeneration is sufficient to cover energy demand. This is now code in California, with solar photovoltaic (PV) systems, highly efficient air filters, heat pump water heaters, and battery
storage combined with improvements for attics, walls, water heating, lighting. It is an all‐electric house.

Does California have it right? In Policy Statement 525, The American Society of Civil Engineers states the purpose of a building code is to establish minimum requirements necessary to protect and improve public health, safety, and welfare in the built environment.

How does a net‐zero energy code help? There are many alliances, associations, advocates, partnerships, and others who are asserting their philosophy of the best way
to answer the question of sustainable home building and renovation. Do so many voices help or cause confusion? It is tough to determine who to listen to among those
listed in the “Referenced Links:” section of this blog.

A good message to rely on came In April 2018. The NewHampshire Office of Strategic Initiatives published the NH 10‐Year State Energy Strategy. For all who want to see
the big picture for NH and New England, this may be the most important single reference. The focus is on “cost effective.”
The Executive Summary begins NH energy prices are among the highest in the nation. On average, each NH resident spent $3,934 on energy in 2015.

Federal sources project that between now and 2050, residential energy consumption will increase overall, with electricity taking a larger role, natural gas remaining
steady, and other energy sources declining. Perspective on the national stage is provided in Figure 7.

Figure 7 Housing & Populations, , Annual Energy Outlook 2021

The Annual Energy Outlook 2021 reinforces that HVAC and domestic hot water dominate residential energy.  Cost-effective choices (e.g., heat pumps, heat pump water heaters) are available and not necessarily new.

Sustainable independence has been explored for decades.  Articles and books tell of folks who started living off the grid back in the 60’s and 70’s.  Pre-photovoltaics, they likely incorporated a home-made solar water heating system.  Some used major passive solar techniques (a.k.a., Trombe thermal storage walls, attached sunspaces, daylighting, shading, etc.).  Wood heating systems were popular too, but home automation wasn’t at the level it is  today.

Along with energy conservation and solar design principles of the 60’s, another concept began.  In 1966, ASHRAE published the first edition of Standard 55, Thermal Environmental Conditions for Human Occupancy.  Human comfort brings the indoor environment into the equation by measuring the occupant element (population and activity producing metabolic heat buffered by clothing insulation), radiant temperatures of surfaces in the space, ambient air temperature (at ankle, waist, and head), air movement/speed, and relative humidity.

The topic of human comfort as measured via ASHRAE 55 is discussed in a blog by SimScale.  It includes the diagram in Figure 8 from an article posted on LinkedIn.

Figure 8 Evaluating occupant thermal comfort.

Research with radiant floor and thermal mass methods of construction indicate that occupant comfort may be a key to energy savings.  Changing the code-focus from today’s convective heat transfer to radiative heat transfer can result in a very comfortable thermostat setting of 65-66 deg-F vs. the code specified design heating temperature of 72 deg-F.  A study performed for 80 mass wood buildings in Finland showed up to a 50% lower measured actual heating demand than the calculated heating

While that sounds simple, it is not. Occupant comfort is a condition of mind that cannot be codified. Perhaps this can change as SimScale continues working to model
occupant comfort.

It appears that Net‐Zero is possible now, that all‐electric homes are happening today, and that heating back‐up systems will be using wood or gas to fuel them.

Greater policy coverage and stringency will be needed according to a study by the International Energy Agency (IEA). Electricity consumption by household appliances
continues to increase … driven by rising ownership of connected plug‐load devices… Mandatory Energy Performance Standards (MEPS) cover one‐third of the
energy used, mainly for large household appliances, but smaller plug loads, including consumer electronics, are less well regulated.

Referenced Links

Click on the hyperlinks that follow to view more information, read articles, and learn about other services available.

Building Energy Experts
Construction Details
Model Codes
  • International Codes Council (ICC,
    • 3‐year cycle (explained here)

The mission of the ICC is to promulgate a comprehensive and compatible regulatory system for the built environment, through consistent performance‐based regulations that are effective, efficient, and meet government, industry and public needs. The NHHBA is a member.

  • NFPA’s Referenced Standards Fact Sheet (for more info)
  • Passive House Institute US (‐page)
  • Vermont Residential Building Energy Standard (RBES)
    •‐use‐of‐the‐2020‐vermont‐residential‐building‐energy‐ standards
    •‐ pdf
ISO/ANSI Accredited Agencies
Federal Resources
NH Resources
Technical Reports/Articles
  • National Green Building Standard Certified Homes Report on Survey Responses (‐content/uploads/2014/01/GuildQuality‐Study‐of‐National‐Green‐Building‐ Standard‐Certified‐Homeowners.pdf)
  • The Trouble With Building Science, Betzwood Associates PC (‐ building‐science/)
  • The Diminishing Returns of Adding More Insulation, posted by Allison Bailes on October 13, 2014 (‐Diminishing‐Returns‐of‐Adding‐More‐Insulation)
  • How to Build a Furnace Enclosure,‐furnace‐enclosure‐20100.html
Resources on air sealing
International Code Council

The NHHBA is a member of the International Code Council (ICC).

The mission of the ICC is to promulgate a comprehensive and compatible regulatory system for the built environment, through consistent performance-based regulations that are effective, efficient and meet government, industry and public needs.

To view all the products and services available from the ICC click here.

In 2006 New Hampshire adopted the IRC 2000 as the state-wide residential building code for one and two family dwellings. Since that time the State Building Code (including the Energy Code) has been updated to the 2015 codes. 2015 IRC Update

NHHBA has a copy of the 2015 International Residential Code (IRC) book in a loose leaf binder format available to members for reference.

Building Code Links & Resources

New Hampshire Building Code Review Board (BCRB) – By statute the NHHBA has a seat on the BCRB.

The State Building Code Review Board is charged with the responsibility for reviewing and recommending to the legislature any adoption of codes in New Hampshire.

New Hampshire Building Officials Association  
Attached is a PowerPoint presentation provided by the NH Building Code Officials outlining the significant changes in the 2015 International Residential Code (IRC). Click Here

NAHB’s Construction Codes & Standards on the web.