Purpose

The Net Zero Energy Residential Test Facility, located at the National Institute of Standards and 

Technology (NIST) in Gaithersburg, MD, enables the 

development and demonstration of measurement 

science needed to achieve net-zero energy 

residential homes that are safe, comfortable, 

and desirable. The facility was initially used 

to demonstrate that a home, typical in size/

features of those in an upscale community in the 

metropolitan D.C. area, can produce as much 

energy from renewable sources as it consumes 

on an annual basis. The facility is subsequently 

being used to generate "real world" field data 

to validate and improve building performance 

models and to improve laboratory based 

measurements of systems and components to 

better represent field performance.

Unique Capabilities

The facility was designed to ensure that it would meet current and future measurement science 

needs to enable the nation to achieve its sustainability 

and comfort goals. The inherent capabilities of this 

facility include: 

• Evaluation of design strategies, technologies, and 

ventilation strategies to provide quality indoor 

environments consistent with energy efficiency 

goals

• Development of the measurement science to 

characterize “as-installed” performance of various 

space-conditioning, water heating, integrated 

systems, and appliances, as well as the building's 

thermal envelope

• Development of the measurement science required 

to capture the efficiency of various techniques for 

distributing conditioned air throughout a residential 

structure

• Improvement and validation of models used to 

predict the energy consumption and indoor air 

quality of buildings

• Studies of earth-coupled heat pump systems using 

various ground-coupling techniques

• Evaluation of methodologies and standards to 

interface with the Smart Grid, and test procedures 

for assessing Smart Grid-enabled appliances

• Evaluation of the relative merits of various building 

control systems and strategies

• Assessment of interactions between the building 

envelope, HVAC systems, and solar systems

• Evaluation of models that predict annual energy 

production of solar energy systems and aid 

modelers in how to best use these models l a b o r ato r y

engineering

Net-Zero Energy 

Residential Test Facility

 la bor ator y

engineering

April 2017

Technical Directors

Brian Dougherty William Healy

brian.dougherty@nist.gov william.healy@nist.gov

(301)975-6396 (301)975-4922

 tinyurl.com/nistnetzero

NIST Engineering Laboratory

Dr. Howard Harary, Director

www.nist.gov/el

Designed and Built in Collaboration with:

Architect of Record

Building Science Corporation

Engineer of Record

EBL Engineers, LLC

Contractor

Therrien Waddell

Subcontractor

Bethesda Bungalows
Unique Features of 

NIST’s Net-Zero Energy 

Residential Test Facility

Building Envelope/Materials 

• Advanced framing and insulation techniques

• Fenestration units easily replaceable

• All ductwork within conditioned space

• Building components selected to minimize heat 

loss/gain

• Basement slab – R-11 1

• Exterior below grade walls – R-25 

• Exterior above grade walls – R-48 

• Roof – R-75 

Photovoltaic System

• Scalable array allowing researchers to select four 

power outputs between 2.6 kW and 10.2 kW 2

• Tandem direct to alternating current inverters 

allow side-by-side test option

• Array layout, instrumentation 

package, and time lapse 

photos aid understanding of 

string level performance

Water Heating and Distribution Systems

• Closed loop solar thermal water heating system and 

multiple collector array size and storage tank capacity configurations

• Capable of providing hot water and/or solar 

assist to earth-coupled heat pump systems

• Heat pump water heater used to supply

water heating requirements not provided 

by solar system

• Highly instrumented water distribution system

Smart Grid 

• Incorporates smart grid meter/network 

capabilities for smart appliances/equipment

Air Distribution Systems

• Multiple zoning capabilities (floor vs high wall 

supplies, perimeter vs central)

• Conventional duct system 

• Small duct, high velocity air distribution system 

• Dedicated ductwork for dehumidification and heat 

recovery systems

Monitoring/Control Systems 

• Lights, appliances, and water use fixtures are 

operated to simulate the use patterns of a typical 

family.

• Every electrical circuit within the facility is 

instrumented to enable measurement of point of 

use energy consumption.

• Instrumentation/control equipment power is 

isolated from the facility both 

electrically and thermally.

Space Conditioning Systems

• Air-to-air central and multi-split heat 

pump systems

• Earth coupled heat pump system with three distinct 

earth coupled fields

• Three vertical well loops (1, 2, or 3 active)

• Horizontal and slinky loops, each 

configurable to 3 different total lengths

Simulated Occupnacy

• User specifies detailed occupancy and activity 

schedule of virtual family

• Schedule implemented by facility's monitoring/ 

control systems

• Occupants' heat and moisture generation emulated

Windows (U-Value <0.2) Photovoltaic Inverters

Mechanical Systems

LED and CF Lighting

Radiant Heat (Future)

Energy Ecient Appliances

Enclosure Penetrations

Solar-Thermal Panels Electric Vehicle Ready

Roof (R-75)

Rim Joist (R-39)

Wall (R-48)

Basement 

(R-25 and R-11)

Photovoltaic Panels (10.2 kW)

1 The R-values (ft2 . °F . h/Btu) 

associated with the various building 

envelope assemblies are approximate

2 The photovoltaic power output is 

the projected output at standard 

reporting conditions

Building Science Corporation