Made up of thirteen different buildings, completed at different times, the Waterbury State Office Complex recently underwent an extensive renovation and rebuild following Tropical Storm Irene. WSOC’s renovation was the largest state building project in Vermont’s state history. The project comprised a New Central Plant of 20,000 gsf, a new office building of 86,000 gsf and seven renovated historic office buildings totaling 115,000 gsf on one campus.  ZbD was involved throughout the design and build process from plan reviews to post-occupancy inspections. 

Built in 1956, Hartford Town Hall's layout was not ideal for a municipal building.  Originally designed as a school building, the dark and narrow hallways complicated the connectivity of various departments.  Zero by Degrees worked with Bread Loaf Corporation and Energy Balance, Inc.

ZbD was recently awarded a 2016 Efficiency Vermont Award for “Major Renovation on a Large Building” for their work on the Hartford Town Hall municipal building.  Our team provided quality assurance testing with infrared imaging, fog, and blower door testing as well as on-site inspections. Congratulations to our fellow team members on this project: Bread Loaf Corporation, Energy Balance, Inc. and Efficiency Vermont for their collaboration.

27 lab rooms and 2 corridors at the recently constructed Vermont Public Health Laboratory required individual air tightness tests to verify compliance with their ultra-low leakage targets. Spaces included several Bio Safety Level 3 (BSL-3) labs. The air tightness specification required the door of each lab room be included in the final leakage reading so using a typical blower door was out of the question. Zero by Degrees followed the specification by measuring leakage through each room’s transfer grill with a calibrated fan and custom enclosure. In a few rooms no transfer grills were present but we were able to adapt by accessing the lab’s isolated supply duct to obtain a leakage reading for the room. In addition to providing a numeric leakage rate for each of the lab rooms we also identified the leakage sites within each room so they could be repaired. Testing the labs in this manner gave us confidence that the contractor would meet the air tightness specification for each of these critical environment labs. By testing through transfer grills and ductwork we were able to catch flaws at the doors that ultimately made the difference in the pass/fail of some of the lab rooms.

The Vermont State Employees Credit Union (VSECU) Rutland Branch took first place in the small new construction category (<15,000 SQ.FT.) 2013 Efficiency Vermont Awards. Zero by Degrees provided infrared and blower door quality assurance testing for the building envelope. With a solid design by Gossens Bachman Architects and excellent workmanship by Russell Construction the Zip System envelope tested out at less than 0.10 CFM50/sf and is among the tightest buildings in the state. VSECU has hired Zero by Degrees to provide the same services for its St. Johnsbury Branch.


 2013 Award Winner - Bennington State Office Building

The 65,000 sf Bennington State Office Building and Superior Courthouse is a 2013 Efficiency Vermont Award Winner in the major renovation category. Zero by Degrees worked with Andy Shapiro of Energy Balance during the construction phase to provide envelope quality assurance testing, window air tightness testing and whole building blower door testing.  




We were hired to commission the envelope of Hypertherm’s LEED certified 3 1/2 acre office and manufacturing facility in Lebanon, NH. 
Despite its size this building went together quickly using insulated metal panels. The panels boast an impressive R43 insulation value but the frequency of panel joints initially made us nervous in the design review phase. Working with the architect and builder we were able to identify and improve the most challenging types of joints. Then, we tested these joints along with window, door, and roof details in the early days of construction to insure they were working before they got repeated throughout the building.  
At substantial completion we had to figure out a way to blower door test a building of this size without the cost being prohibitive. The earlier quality assurance tests gave us a good indication that the building was working but we needed blower door testing to actually quantify the shell. Working with the builder we isolated two large representative sections of the building for blower door testing.

Sheldon Towers is a 10 story senior housing complex in Rutland, VT. The challenge on this blower door test was working with the tenets on every floor to get the test done accurately without compromising safety or security. The housing authority staff was great to work with as we developed a plan, notified the tenants several days in advance, and carried out the test one June evening.




Finished in 2010, the Vermont State Forensics Laboratory is a 30,000 s.f. state of the art crime lab attached to the existing State Police headquarters in Waterbury, VT. The building had a strict air tightness standard and we were hired to find out if the standard had been met.  
The first task was to “separate” the new lab from the existing State Police headquarters so the air leakage from just the lab could be isolated. This was done with a balanced pressure blower door test to create a neutral pressure across the common wall between the 2 buildings. For security reasons blower fans had to be placed quickly and the controls and metering instruments had to be located outside so the state police headquarters would remain secure and undisturbed during testing. The balanced pressure blower door test revealed that 1400 CFM50 of the total air leakage was not true leakage to the outdoors, but leakage through the common wall between the 2 buildings.  
The second task was to locate the air leaks that remained in the envelope of the new lab. These were located by pressurizing the building with the blower door fans and checking suspect areas with theatrical fog.

SUNY Plattsburgh 6-14-12 065.jpg

Recently renovated Hood Hall at SUNY required the storefront windows to be tested in accordance with AAMA 501.2, a water penetration test using a calibrated nozzle to spray every linear foot of the glazing frames. Significant time was put in to carry out the test of 3 large storefronts which would be representative of the rest of the storefronts throughout the building. Testing showed that the windows were water tight except for one clogged weep; a discovery made after thoroughly retesting and investigating the window details for points of entry and areas of pooling.


The east wing of the Putney Central School needed an overall assessment of the insulation and air barrier systems to anticipate improvements that could be made at the same time as other construction projects. The wing was assessed with guarded blower door testing in order to mitigate air flow from the rest of the building, a comprehensive R-value survey, and infrared thermography; all data that proved to be useful in making final recommendations.


This building has been a brewery and a bottling company and now exists as the headquarters for Cover Home Repair, a non-profit that helps people get needed home repairs with teams of volunteers under the direction of a professional contractor. The building has a haggard appearance but is really a diamond in the rough. Cover Home Repair approached Zero by Degrees to help them develop a long term energy plan for the building with a goal of net zero energy use. With the remnants of past use throughout the building and multi vintage construction the energy audit was a challenge but by no means a lost cause. In fact, the building’s unique attributes made “net zero” even more a possibility: a large cistern in the basement that could be used for hot water storage and a defunct freight elevator shaft that could facilitate electrical and HVAC upgrades were among the findings.

Enclosure Commissioning - Middlebury College Fletcher Hall

Originally built in the 1860s Fletcher Hall was renovated in 2010-2011 into 5 faculty apartments inside 8700 sf. Envelope commissioning included a blower door and pressurized fog evaluation of the existing conditions, envelope design review, a quality assurance milestone test during construction and a final test near the end of construction. The challenge on this building was that the renovation scope included only selective demolition so new envelope components had to be fully integrated with existing envelope components to form a continuous air, vapor, and thermal barrier. In addition, the air barrier standard had to be set with an understanding that some areas would not be accessible for improvement. In the end the building improved air tightness by 47% and exceeded its air tightness target by 22%.


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