Tuesday, July 8, 2008

Developing the Building Envelope Workforce and Infrastructure to Reduce Maine's Dependance on Energy

With oil over $140/barrel and climbing and $4.70/gallon in Maine, I wanted to raise the alarm about a major component of heating costs in Maine that is within reach of being dramatically reduced. It is in the area of the building envelope, otherwise known as “weatherization” or “tightening up” or “insulation”. However, despite a well established understanding of the problem and how to fix it from a technical standpoint, there exists a massive lack of infrastructure in Maine and the nation to retrofit buildings.

Essentially, there is a huge problem with poor performance of building envelopes in Maine. I think it would be conservative to estimate that 1/3 of the total energy used to heat Maine buildings is wasted due to excess air leakage (infiltration) and poorly insulated surfaces. This has all been well documented.

The following Study by the LBNL details where the heating energy is going, including that to ascribe to infiltration.

Residential Heating Loads


Commercial Heating Loads


A good overview of the “state of the art” on building air tightness is here: http://buildingairflow.lbl.gov/pubs/LBNL53356.pdf

A report by the National Institute of Standards has indicated that over 1/3 of the heating energy load is a result of infiltration and that commercial buildings are not as tight as often thought. They state that reducing air leakage to a target standard could result in savings of up to 36% in the coldest climates. Much of that report is summarized in the Winter 2007 issue of the Journal of Building Enclosure Design http://www.nibs.org/JBED/JBED_Winter07.pdf on page 16.

In the same issue, on page 42, is a description of the adoption of air tightness standards to fix the Carbon emissions problem and energy cost of leaky commercial buildings in the UK. There is a routine blower door testing of large commercial buildings in the UK and retrofitting to meet standards.

The Cost of Energy Waste from Building Envelope Deficiencies in Maine

In trying to quantify what constitutes 1/3 of the total heating cost of the state of Maine, I refer to the following tables and only pull out the figures on “distillate fuel” which I take to be #2 heating oil.

Residential heating of 49.1 trillion Btu: http://www.eia.doe.gov/emeu/states/sep_sum/html/sum_btu_res.html

Commercial heating of 16.8 trillion Btu: http://www.eia.doe.gov/emeu/states/sep_sum/html/sum_btu_com.html

Total distillate fuel in Maine in 2005 according to these charts is 65.9 trillion Btu (49.1+16.8). There is 139,400 Btu in a gallon of #2 oil so this converts from 65.9 trillion Btu to 473 million gallons of oil.

473 million gallons of oil @ $4.50/ gallon will cost Mainers $2.13 billion dollars. Burning a gallon of oil produces 22.38 lbs of CO2, burning 473 million gallons of oil produces 5.29 million tons of CO2.

I would estimate conservatively that building envelope deficiency in Maine is about 25% of total heating energy. I have personally witnessed the obnoxious problems that many larger buildings have, new and old, and residences. Our residential clients have experienced dramatic reductions in energy consumption, some of them experienced reductions of about 40-50%!

Of the 25% reduction, I estimate that at about half of the reduction (12.5% of consumption) could be accomplished with improvement costs that would result in a 5 year payback or less (the low hanging fruit). The other half could reasonably have a 10 year payback at current prices.

Total Cost of Oil Consumption in Maine: $2.13 billion

Estimated Reductions of 25% from building envelope improvements: $532 million

Estimated Reductions of 12.5% defined as “low hanging fruit”: $266 million

Cost of Low Hanging Fruit Improvements (payback of 5 years): $1.33 billion

Estimated Reductions of 12.5% defined as longer payback: $266 million

Cost of longer payback items (payback of 10 years): $2.66 billion

Total cost of improvements to achieve 25% reduction: $4 billion

Based on these assumptions, there could be an astronomical investment in building envelopes in Maine, for which there is no infrastructure of contractors and workers to do the work. We need a massive expansion of skilled building envelope technicians in Maine and the nation.

Technical and Training Resources for Building Envelope

There is no shortage of information, research, and technical knowledge to support the effort, much of which is old knowledge published over a decade ago. There just needs to be an infrastructure. Here is a sampling of these resources.

Envelope Design Guidelines for Federal Office Buildings: Thermal Integrity and Airtightness (a NIST publication from 1993 detailing guidelines for the building envelope for the GSA)


Affordable Comfort (an organization devoted to advancing home performance, much of which deals with building envelope. They hold regional conferences for training these skills) Perhaps Maine should host an Affordable Comfort conference ASAP to kick start the industry in Maine. They have done some pioneering work in deep energy reductions of residential buildings as detailed in this white paper. On page 28 they list things that local governments can do.


Maine Home Performance (a program started in 2006 to train home performance evaluators, geared to residences and a whole house approach, essential to dealing with Maine’s older housing stock with wet basements)


MSHA has been working in the field of training “weatherization” for decades and may have resources to expand.

Building Performance Institute is a leading credentialing organization which has a published standard for a Shell Professional (otherwise known as a Building Envelope Technician or Specialist) http://www.bpi.org/documents/Shell_Standards.pdf which is a great place to start.


Saturn Resource Management publishes text books and guides including Residential Energy (used by Maine Home Performance and MSHA Energy Auditor Courses) They have recently published a Building Shell Field Guide http://www.srmi.biz/Bookstore.Professionals.Building_Shell_Field_Guide.htm. which I have yet to see but have high hopes for it being a helpful training tool and guide.


British Resource Establishment (BRE) has been instrumental in implementing a testing and improvement of airtightness in the UK. They may be able to provide important technical development and support should Maine adopt a serious plan on addressing leakage of large commercial buildings. They appear to be world leaders in this field.


Rick Karg of R.J. Karg Associates (an experienced trainer in energy efficiency for decades who has written weatherization standards for several states and is well qualified to guide the process of training and development of infrastructure. He is the lead technical trainer of Maine Home Performance and has been a trainer for MSHA’s energy auditor trainings.


Growing the Workforce and Infrastructure

While there are many incentives for Mainer’s to invest in energy improvements (such as MSHA HELP loan program funds or just the high price of energy), there is almost no current infrastructure to effectively take care of this demand. There are existing insulation contractors but I would estimate that less than 25% are compentent in airsealing. Of that 25%, precious few have the standard tools to do it effectively (namely the blower door and infrared camera).

With my estimate of building envelope work that can be done cost effectively being about $4 trillion, Maine is no where near being able to put a dent into this problem.

A well trained building envelope techician must have the building science knowledge, diagnostic skills, and capability of performing work that results in energy savings. Training needs to be as rigourous as other licensed trades such as plumber, electrician, and heating technician. A building envelope technician is responsible for ensuring indoor air quality, adequate insulation, moisture control, and air tightness. It can involve everything from installing a sump pump to drain a wet basement, installing vapor barriers over dirt floor basement and crawlspaces, basement insulation and air sealing, attic air sealing, blower door guided airsealing, proper mechanical ventilation for kitchens and bathrooms as well as whole house air quality, wall and attic insulation, attic ventilation, etc.

It is a surprise to many that tightening up a house involves more than weatherstripping and caulking. There is a so much more that needs to be considered to control heat, air and moisture to support the health, safety, and comfort of a buildings occupants while also ensuring the durability and efficiency of the structure. This knowledge base and approach is at the core of Home Performance with Energy Star. Since the laws of physics govern results of improvements, knowledge of building science is essential to design successful solutions consistent with the physics. This is high skill work.

In order to develop this work force, the state’s educational system needs to be brought in, from the University to the Tech Colleges and Schools. However, the first problem to be solved is developing a way to train the trainers who will then need to train the technicians. The field is so new that building significant infrastructure will take time.

Incentives to Existing Contractors

Existing contractors, such as our company, are facing great hurdles for expansion to meet incredible market demand. Much of what our company faces is no different than any other company faces in the start up phase, financing, management, systems building, etc. Added to this problem is the prohibitive cost to self train in this pioneering field and to find and train new workers. Established trades such as electricians, plumbers, etc already have an infrastructure. Home performance contracting companies will need a workforce to expand.

If the state invests significant resources to finance energy efficiency improvements with out an infrastructure to provide those services, they are in effect giving out reduced price train tickets when there are no trains in the station. Contractors need financing to grow their business to serve the public demand, to purchase the diagnostic equipment (blower doors and infrared cameras) to do high quality work, to train their workforce and develop systems.

What about the Energy Auditors supporting Building Envelope Improvement

The efforts by MSHA and Maine Home Performance to expand the pool of energy auditors in this state is a very important step in diagnosing buildings and Maine and finding opportunities for savings. However, the diagnostic tools that auditors use to evaluate the home are essential to the improvement of the home. It is essential that these same advanced tools be available to the contractors creating the improvements. I have found from personal experience of both evaluating and fixing homes, that in the course of doing work, especially airsealing, initial conclusions in the audit phase where often quite different in the course of improvement work. Assumptions made turn out to be wrong. The workscope needs adjustment, sometimes dramatically, to reflect found conditions.

The auditor, as consultant, could of course be brought in every time, and be available to test out at the end but the real success of an improvement lies with the technician installing the improvement.

It is no different than walking into a modern hospital with modern equipment and getting diagnosed by a skilled doctor / surgeon and have surgery recommended. However, instead of the doctor doing the surgery, the patient gets referred to a list of uncertified people that do the surgery on the kitchen table without the high tech tools used in modern hospitals.

BPI has a Building Analyst certification which corresponds to “energy auditor” as the basic level credential. A Shell Specialist (Envelope Tech) is a more advanced certification requiring the Building Analyst designation as a pre-requisite. It takes more specialized skill to actually achieve energy improvements than to diagnose them.

It is really no different than an energy auditor finding that a heating system really needs improvement or replacement and the improvement work being done by a licenced heating technician. The auditor is essentially an energy efficiency reconnaissance professional, focused on identifying opportunities. Airsealing work, in particular, is something that most auditors simply don’t have direct, first hand experience in. For this reason, the most experienced people in diagnosing and fixing air leakage problems should be the ones doing the improvement. Therefore, they need the blower doors and infrared cameras, etc as well as the training to use them effectively.

I would even go so far as to argue that MSHA or any other state funding source shouldn’t be financing air sealing work done by contractors that don’t have this equipment and training. Providing contractors with the equipment through leasing or financing or grants while also requiring them to use them and record air sealing improvement results would be a carrot and stick approach that would benefit Mainers by increasing the effectiveness of work done and paid for.


With an energy crisis facing Maine, it is a shame to ignore a major gap between significant portion of the energy problem and its solution. It is my belief that the building envelope improvement will emerge as one of the most significant sources of reducing energy usage for Maine.

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About Me

Richard Riegel Burbank founded Evergreen Home Performance LLC in 2006. The Rockland, Maine based company provides building diagnostics and building envelope installation and renovation. Their projects range from installing cellulose in new construction and retrofit, air leakage reduction in residential and commercial buildings, and moisture mitigation in basements and crawlspaces. He is one of the first Building Performance Institute certified analysts in Maine, and an affiliated contractor with Maine Home Performance with Energy Star and ZeroDraft.