ABAA Field Auditor cheat sheet

Air barrier systems limit unintended air flow; insulation limits heat flow; vapor retarders limit vapor diffusion. These functions are separate and must be evaluated separately.

Pressure difference across the envelope: ΔP = ΔP_wind + ΔP_stack + ΔP_mechanical. Leakage direction and rate depend on the sign and magnitude of total ΔP.

Orifice flow approximation: Q = C_d A sqrt(2 ΔP / ρ), where Q is volumetric flow, A is leakage area, ΔP is pressure difference, and ρ is air density.

Stack effect increases with building height and indoor-outdoor temperature difference; in cold weather, warm buoyant indoor air tends to exfiltrate at upper levels and infiltrate at lower levels.

ACH50 = (CFM50 × 60) / building volume; CFM50 is measured airflow at 50 Pa and volume is conditioned building volume in cubic feet.

In cold climates, exfiltration can carry moist indoor air into cold cavities and cause condensation; in hot humid climates, infiltration can carry moist outdoor air to cool interior surfaces.

Continuity must be maintained across wall-roof, wall-floor, fenestration, penetration, and material-change interfaces; discontinuities are common leakage sites.

Air permeance of a material and air leakage of an assembly are different metrics; material data cannot by itself prove joint and penetration performance.

Common air barrier materials include sheet membranes, fluid-applied membranes, rigid board sheathing with sealed joints, closed-cell spray foam, and sealed concrete or masonry.

ASTM E2178 reports material air permeance at 75 Pa in L/(s·m2); lower values indicate greater resistance to airflow.

ASTM E2357 evaluates assemblies with joints and penetrations at 75 Pa; it is the appropriate basis for judging installed system leakage rather than material-only data.

Accessory selection rule: tapes, sealants, primers, and membranes must be compatible with substrate and with each other; follow manufacturer limitations for temperature, moisture, UV, and cure.

Sealant joints require clean, dry, compatible surfaces, correct joint dimensions, continuous contact, and tooling; adhesion failure or cohesive failure both create leakage risk.

Mechanical fasteners must be specified by type, length, spacing, edge distance, and washer; overdriving can tear membranes and create leakage paths.

Vapor permeance and air permeance are independent properties; a vapor-permeable material can still be an effective air barrier if joints and penetrations are sealed.

ASTM E2178: material air permeance. ASTM E2357: air barrier assembly leakage. ASTM E283: laboratory air leakage of fenestration. ASTM E783: field air leakage of installed fenestration.

ASTM E779 and ASTM E1827 cover fan pressurization testing of building airtightness; ASTM E1186 covers air leakage site detection practices.

Material and assembly air leakage tests commonly use 75 Pa; whole-building airtightness tests commonly report airflow at 50 Pa (CFM50 or ACH50).

Specifications should define products, substrates, joint treatments, mockups, test standards, acceptance criteria, retest conditions, and documentation.

Codes such as IECC and ASHRAE 90.1 require continuous air barriers; compliance can be shown through listed materials and assemblies or envelope testing, depending on the adopted code path.

Test reports must state standard, specimen or building description, pressure differences, airflow, normalized results, equipment, calibration, and test conditions.

Acceptance criteria must be fixed before testing; changing criteria after results are known invalidates the audit conclusion.

Surface preparation rule: substrates must be clean, dry, sound, and compatible with primer or adhesive; dust, oil, frost, and moisture can prevent bond.

Membrane laps follow manufacturer direction and width; shingle-lap upper courses over lower courses where drainage or water shedding is required.

Sealant beads must be continuous at transitions and penetrations, with proper width-to-depth ratio and tooling; voids and fisheyes are rejectable.

Fasteners and washers must be installed to specified spacing and embedment without overdriving, tearing, or pillowing the membrane.

Penetrations require sealing on the air barrier side and at penetrations through sheathing; sleeves, gaskets, and flexible membranes accommodate movement.

Sequencing rule: complete and inspect air barrier work before concealment by cladding, drywall, or insulation; protect exposed materials from UV and weather per manufacturer.

Repair rule: patches must extend beyond damaged area, use compatible material, and restore continuity; repairs are documented and inspected before closeout.

Workmanship verification checkpoints: substrate condition, transitions, joints, fasteners, penetrations, terminations, and protection.

Audit planning starts with scope, criteria, schedule, roles, documents, sampling plan, safety plan, and communication protocol.

Document review includes drawings, specifications, submittals, RFIs, test reports, inspection logs, calibration records, and prior nonconformances.

Risk-based sampling prioritizes complex transitions, penetrations, repairs, repeated details, inaccessible areas, and locations with high moisture or pressure risk.

Random sampling within defined strata reduces selection bias; record sampling frame, random method, sample size, and locations.

Sample size should be justified by audit objective, population size, risk, and confidence needed; convenience samples must be labeled as such.

Chain of custody records who collected, handled, transported, and tested samples or evidence; it includes dates, times, locations, and signatures.

Inspection records should capture location, detail type, requirement, observed condition, photo number, and auditor initials at the time of observation.

Access and safety constraints must be documented; auditors do not inspect unsafe or unauthorized areas without controls and permission.

Blower door test procedure: prepare building, close intentional openings, measure baseline, install calibrated fan, record pressure-flow points, and calculate normalized leakage.

ASTM E779 provides a fan pressurization method; ASTM E1827 provides building airtightness determination; ASTM E1186 provides leak-site detection practices.

Test conditions to record include indoor and outdoor temperature, wind, baseline pressure, building volume, fan configuration, and gauge calibration.

Smoke tracer locates leaks under pressure; infrared thermography locates temperature anomalies, but interpretation requires suitable ΔT, emissivity, and pressure.

Chamber testing evaluates mockups or assemblies under controlled pressure; field testing evaluates installed work and includes real joints, penetrations, and transitions.

Manometers and gauges must be zeroed, ranged appropriately, and calibrated; pressure tubing must be protected from wind and kinks.

Results must be interpreted against pre-established criteria and reported with uncertainty and anomalies; a single pass/fail number does not identify defect locations.

Diagnostic sequence: visual inspection, pressure test, leak location, repair, and retest.

Report contents: scope, criteria, methods, equipment, calibration, test conditions, results, photographs, nonconformances, conclusions, and limitations.

Nonconformance record: requirement, location, observed condition, evidence, severity, responsible party, correction required, and due date.

Corrective action follows sequence: contain or correct, root-cause analysis, preventive action, verification, and closure.

Closeout requires objective evidence such as photos, inspection sign-off, material records, and retest results; verbal assurances are insufficient.

Distinguish observations from findings: observations describe conditions; findings state verified noncompliance against a specific requirement.

Records should be legible, dated, signed or initialed, and retained according to contract and program requirements.

Reports must separate facts from opinions and identify limitations, exclusions, and areas not inspected.

Follow-up tracking should include open items, responsible party, due date, status, and verification date.

Ethical rules: disclose conflicts of interest, avoid gifts or inducements that affect judgment, protect confidential information, and audit only within competence.

Impartiality requires findings based on evidence and criteria, not on client pressure, prior relationships, or desired outcomes.

Before site work, review hazard assessment, site rules, permits, utility clearance, access control, and emergency procedures.

PPE selection follows task hazards: head, eye, hearing, respiratory, hand, foot, and fall protection as required.

Fall protection is required when working at heights or near unprotected edges; use guardrails, nets, or personal fall arrest systems with suitable anchors.

Blower door testing can affect combustion appliance draft; assess CO and backdrafting risk, and follow safety procedures before operating fans.

Stop work and report imminent danger or serious noncompliance; do not enter unsafe areas or operate equipment without authorization.

Hazard communication includes knowing chemical labels and safety data sheets for sealants, primers, solvents, and spray foam.