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Say What? A Quick Guide to Building Science Jargon

By Katie Weeks


What do MEC, NPP, and RTFM mean? Here's a hint: They're not texting shorthand; they're building science acronyms. Some, like NZE (or net zero energy) may be common vocabulary for some practitioners, but others such as, say, SDO (Standards Development Organization, an ANSI designation), may not be as commonly known. And then there's the challenge of subtlety. An REC, for example, or more specifically its plural form, RECs (renewable energy credits, for those of you wondering), is not the same as RECS (Residential Energy Consumption Survey). With all the jargon floating out there, it could make you think you need a PhD to keep track of it all.

Luckily, one PhD has taken the challenge on. For the past few years, energy consultant and RESET-certified trainer Allison Bailes (who has a PhD in physics) has been compiling a master list of must-know building science (aka BS) acronyms and initials that are handy for all green building practitioners to know. So far, he has compiled 153 terms and not only lists the top 50 over at Green Building Advisor, but also offers up a full downloadable list or Excel sheet. (PS: He's also categorized common HERS lingo on his site, Energy Vanguard.)

My favorite of them all? SWAG, or scientific wild-ass guess.

And speaking of linguistics, we're still keeping a running list of overused or outdated green building terms that we started at the end of last year. Add your picks to the mix here.

Source: Katie Weeks, Eco Building Pulse. January 9, 2014.

For the original article please click here.


Top 50 picks from Green Building Advisor. 

Acronym What it stands for  
AAC autoclaved aerated concrete  
ABAA Air Barrier Association of America  
ACCA Air Conditioning Contractors of America  
ACH50 air changes per hour at 50 Pascals  
ACHnat air changes per hour natural  
ACI Affordable Comfort Inc.  
ADA another damn acronym (although this would really be initials)  
ADA Americans with Disabilities Act  
ADC Air Distribution Council  
AFUE annualized fuel utilization efficiency  
AGW above-grade wall  
AHJ authority having jurisdiction  
AHRI Air Conditioning, Heating, and Refrigeration Institute  
AHU air handler unit  
ANSI American National Standards Institute  
APHN American Passive House Network  
ASHP air-source heat pump  
ASHRAE Amer. Soc. of Heating, Refrigerating, and Air-conditioning Engineers  
ASTM American Society for Testing and Materials  
BA Building America  
BAS building airflow standard  
BCAP Building Codes Assistance Project  
BOP Builder Option Package  
BPI Building Performance Institute  
BS building science  
BSC Building Science Corporation  
BTL building tightness limit  
BTU British Thermal Unit  
CAZ combustion appliance zone  
CCF hundred cubic feet  
CDD cooling degree days  
CFA conditioned floor area  
CFL compact fluorescent lamp  
cfm cubic feet per minute  
cfm50 cubic feet per minute at 50 Pascals  
CHP combined heat & power  
CO carbon monoxide  
CO certificate of occupancy  
CO2 carbon dioxide  
COP coefficient of performance  
CYA cover your ass  
CZ climate zone  
DIY do it yourself  
DOE Department of Energy  
ECM electronically commutated motor  
EEM energy efficient mortgage  
EER energy efficiency ratio  
EF energy factor  
EFL Environments for Living  
EIA Energy Information Administration  
EIM Energy Improvement Mortgage  
ELA envelope/enclosure leakage area  
ELR Envelope/Enclosure Leakage Ratio  
EPA Environmental Protection Agency  
EPS expanded polystyrene  
EqLA equivalent leakage area  
ERV energy (or enthalpy) recovery ventilator  
ES / ESTAR Energy Star  
ES V3 Energy Star version 3  
FHA U.S. Federal Housing Authority  
FLA four letter acronym or five letter acronym  
FROG finished room over garage  
GBA Green Building Advisor  
GC general contractor  
GSHP ground-source heat pump  
GWP global warming potential  
HDD heating degree days  
HEPA high efficiency particulate air  
HERS Home Energy Rating System  
HOT2000 A type of Canadian energy modeling software  
HP home performance  
HPwES Home Performance with Energy Star  
HRV heat recovery ventilator  
HSPF heating season performance factor  
HUD U.S. Department of Housing and Urban Development  
HVAC Heating, Ventilating, & Air Conditioning  
IAQ indoor air quality  
ICAT insulation contact, air tight (designation for recessed can lights)  
ICC International Code Council  
ICF insulated concrete form  
IEA International Energy Agency  
IECC International Energy Conservation Code  
IEQ indoor environmental quality  
IR infrared  
IRC International Residential Code  
IREC Interstate Renewable Energy Council  
iwc inches of water column (pressure unit)  
iwg inches of water gauge (pressure unit, same as iwc)  
KISS keep it simple, stupid  
LBL Lawrence Berkeley Laboratory (old name, still used by some)  
LBNL Lawrence Berkeley National Laboratory  
LCA life cycle analysis  
LED light emitting diode  
LEED Leadership in Energy & Environmental Design  
LEED AP LEED Accredited Professional  
MEC Model Energy Code  
MERV Minimum Efficiency Reporting Value  
NAHB National Association of Home Builders  
NAPHN North American Passive House Network (a.k.a. APHN)  
NASEO National Association of State Energy Offices  
NATE North American Technician Excellence  
NCI National Comfort Institute (not to be confused with Comfort Institute)  
NIST National Institute of Standards and Technology  
NPP neutral pressure plane  
NPV net present value  
NREL National Renewable Energy Laboratory  
NZE Net Zero Energy  
OCEAN Online Code Environment and Advocacy Network  
OEM original equipment manufacturer  
ORNL Oak Ridge National Laboratory  
OSB oriented strand board  
OVE Optimal Value Engineering (includes advanced framing)  
PDW pre-drywall  
PHAUS Passive House Alliance U.S.  
PHIUS Passive House Institute U.S.  
PM project manager  
PPE personal protective equipment  
PSC permanent split capacitor  
PTAC packaged terminal air conditioner  
PTHP packaged terminal heat pump  
PV photovoltaic  
PV present value  
QA quality assurance  
QAD Quality Assurance Designee  
RECS Residential Energy Consumption Survey  
RESNET Residential Energy Services Network  
RH relative humidity  
RTFM read the friendly manual  
SDO Standards Development Organization (ANSI designation)  
SEER seasonal energy efficiency ratio  
SFBE square footage of building enclosure  
SHF or SHR sensible heat fraction (or ratio)  
SHGC solar heat gain coefficient  
SIP structural insulated panel  
SIPA Structural Insulated Panel Association  
SIR savings investment ratio  
SMACNA Sheet Metal and Air Conditioning Contractors' National Association  
SPF spray polyurethane foam  
SPFA Spray Polyurethane Foam Association  
SWAG scientific wild-ass guess  
TESP total external static pressure  
TLA three letter acronym  
TXV or TEV thermal expansion valve  
USGBC U.S. Green Building Council  
VOC volatile organic compound  
VRF variable refrigerant flow  
VRV variable refrigerant volume  
WRB water-resistive barrier (not weather-resistant barrier)  
wrt with respect to  
WUFI Wärme-und Feuchtetransport instationär  
XPS extruded polystyrene  
ZEB zero energy building (should be 'net' zero)  
ZPD zone pressure diagnostics