A measured, evidence-based look at your building
A building envelope assessment is a one-shot engagement that combines measurement, diagnostics, and visual inspection to characterize how an existing building's envelope is actually performing — and what's most worth doing about it.
Every assessment is anchored in measured data: a multi-point blower-door test to ASTM E779, guided air leakage diagnostics under depressurization, and infrared thermal imaging to localize leaks and thermal weak points. The result is a prioritized written report that owners, architects, and code officials can all act on.
Engagements are led and executed directly by Nate Gusakov, CxA+BE, BECxP, BPI Building Analyst-Professional, RESNET HERS Rater, and ABAA Certified Whole Building Airtightness Technician — with a background as a working carpenter and project manager that informs every diagnostic call.
Standard assessment scope
Most assessments include some combination of the following. Scope is tailored to the building and what the owner or owner's rep needs to learn.
Whole-building airtightness testing
Multi-point blower-door testing to ASTM E779 to establish the building's air leakage rate at standard reference pressures (50 Pa, 75 Pa).
Guided leakage diagnostics
Systematic walk-through under depressurization using smoke pencils and tracing agents to locate and photograph specific air leakage pathways.
Visual envelope inspection
Methodical visual inspection of exterior and interior envelope components — cladding, windows, doors, roofline, foundation transitions — noting defects and risk conditions.
Infrared thermal imaging
Calibrated interior and exterior IR scans during the blower-door test to localize thermal bridging, missing insulation, and concealed air leakage.
QLoss energy loss modeling
Efficiency Vermont's QLoss spreadsheet tool applied to the measured leakage data to quantify seasonal energy penalty and prioritize repairs by payback.
Written assessment report
A consolidated report with measured results, photo-documented findings, prioritized recommendations, and any supporting IR or diagnostic imagery.
Who assessments are for
A building envelope assessment is the right call when you need objective, documented answers about an existing building's performance:
- Owners considering major envelope work — municipalities, institutions, non-profits, or private owners weighing weatherization, re-cladding, or deep energy retrofits and needing a defensible basis for scope.
- Owner's representatives specifying baseline testing before a capital project — typical on historic institutional and mixed-use buildings in Vermont.
- Architects doing pre-renovation due diligence on an existing envelope before designing interventions.
- Buildings with performance complaints — comfort issues, high energy use, ice dams, moisture stains, or indoor air quality concerns rooted in envelope performance.
- Incentive and code-driven projects requiring documented pre- and post-airtightness results (Efficiency Vermont, VT RBES/CBES, other state programs).
Recent work. Rutland Free Library (historic institutional, ~34,948 ft²) · 128 King Farm Rd, Woodstock (Vermont Land Trust, ~10,995 ft²) · 195 Colchester Ave, Burlington (UVMMC, ~33,000 ft²).
Assessments are priced as a lump sum based on the building's total conditioned floor area. Field work typically runs 6–10 hours on site for a single building, with a final written report delivered within about two weeks.