ADVANCED BUILDING ENVELOPE TESTING
Air, Water, & Thermal Performance Evaluations

Hightower Labs specializes in building envelope testing, providing precise air, water, and thermal performance evaluations to ensure compliance with ASTM standards and industry best practices. Whether you need to diagnose leaks, verify air infiltration rates, or assess thermal efficiency, our testing services deliver the data you need to make informed decisions.

Hightower Labs delivers precise, independent testing services to assess the performance of building envelope systems under real-world conditions. Using advanced methodologies and industry-standard procedures, we provide lab-quality data that objectively measures critical factors such as air tightness, water resistance, and thermal performance. Our comprehensive testing ensures that envelope components meet design expectations, comply with regulatory standards, and perform reliably over time—whether for new construction, retrofit projects, or forensic investigations.

ASTM E1105 test viewed from the interior, on a large curtain wall system

TESTING SERVICES OVERVIEW

At Hightower Labs, we specialize in evaluating and improving the performance of building envelope systems. Our completed projects, some of which are showcased here, reflect our commitment to precision, problem-solving, and delivering actionable insights for building owners, developers, and design professionals.

Air Infiltration Testing (e.g. ASTM E779)

  • Measures overall air leakage rate of an entire building or enclosed space.
  • Utilizes blower door testing to quantify air permeability and infiltration/exfiltration rates.
  • Helps identify building envelope deficiencies, energy loss, and HVAC inefficiencies.
  • Supports compliance with energy codes, LEED, Passive House, and airtightness standards.
  • Ideal for new construction, existing buildings, and energy performance diagnostics.


Leak Assessment - Water Penetration Testing (e.g. ASTM E1105)

  • Evaluates water penetration resistance of windows, curtain walls, and other exterior wall assemblies.
  • Uses a calibrated spray rack to apply water at a controlled rate while subjecting the specimen to uniform air pressure.
  • Measures whether water penetrates beyond the innermost plane of an assembly under specified conditions.
  • Does not simulate real-world weather but provides a standardized test environment for performance evaluation.
  • Commonly used for new construction quality assurance, forensic investigations, and product validation.

ASTM E1105 test viewed from the interior, on a large curtain wall system

Why Choose Hightower Labs?

At Hightower Labs, we provide industry-leading building envelope testing designed to ensure long-term performance, durability, and compliance for commercial, institutional, and high-performance buildings. Our expertise, precision, and commitment to actionable results set us apart from standard testing providers.

Industry-Leading Expertise

    Our team brings decades of specialized experience in building envelope diagnostics, forensic investigations, and performance testing. We understand not just how to conduct ASTM-standardized tests, but how to interpret results in real-world conditions to provide practical, actionable solutions.

  • BECxP, CxA+BE Certified Staff – Recognized experts in building enclosure commissioning (BECx).
  • BPI accredited & required certifications for test procedures, calibration, and equipment.
  • Forensic Building Specialists – We go beyond testing to help diagnose failures and recommend targeted solutions.
  • Trusted by Architects, Developers, and Consultants – Our testing helps ensure code compliance, risk mitigation, and long-term asset protection.

Precision Testing Adheres to Standards

    Hightower Labs specializes in air, water, and thermal performance evaluations that go beyond the minimum industry requirements to deliver high-confidence results.

  • ASTM-Compliant Testing – We strictly follow and exceed standards such as ASTM E1105 (Water Penetration), ASTM E779 (Air Infiltration), and AAMA 501.2 (Field Water Testing).
  • Advanced BEAM 03 Methodology – Our proprietary BEAM 03 test provides higher reliability than ASTM E1105, ensuring a more comprehensive assessment of water resistivity.
  • Controlled and Repeatable Testing Conditions – Unlike unreliable in-field evaluations, we provide data-driven performance verification under controlled conditions.

Data-Driven Solutions & Actionable Insights

    We don’t just run tests—we interpret the results and provide solutions that help owners, architects, and contractors make better, more informed decisions.

  • Detailed, Engineering-Level Reports – Every test includes a clear, data-driven report outlining findings.
  • Root Cause Analysis – If a failure occurs, we can help diagnose the issue and develop practical remediation strategies.
  • Pre- and Post-Construction Support – Our work extends beyond new builds, offering testing for existing buildings experiencing water intrusion, air leakage, or thermal inefficiencies.

Trusted by Industry Leaders

    Hightower Labs has worked on commercial office towers, mixed-use developments, hospitals, universities, government buildings, and high-performance residential projects. Our clients trust us because we provide:

  • Unbiased, Third-Party Testing – We are independent and do not sell products nor maintain working relationships with manufacturers, ensuring completely objective evaluations.
  • Support for Litigation & Expert Witness Testimony – Our data is frequently used in dispute resolution, defect claims, and liability determination.
  • National Reach with Local Expertise – While headquartered in Chicago, we perform building envelope testing across the U.S.

Protect Your Investment with Hightower Labs

Whether you’re constructing a new building, diagnosing a leak, or verifying envelope performance, Hightower Labs delivers the highest level of expertise and accuracy in building envelope testing.

Contact Us Today to discuss your project and schedule testing

E-mail: service at hightower-labs.com

Phone: 312.897.3742



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Air Tightness of the Building's Envelope

Comfort & Energy

Air barrier code criteria have been introduced slowly, in measured increments, are heavily balanced by manufacturer and contractor incumbrance, and are therefore not stringent. A code-compliant thermal envelope is both relatively energy-efficient and easy for your builder to achieve.

Hightower Labs conducting ASTM E779 air tightness field testing for building envelope systems.

There is little reason to fear test validation for air barrier code compliance with modern budgets, materials, and design/install practices. Even the most egregiously-detailed projects have a decent chance to meet 0.4 cfm/ft² @ 75 pa, and we offer cost-efficient pre-test diagnostic reviews that offer recommendations for improvement and make the results known prior to the formal test.

For ASHRAE 90.1, IECC 2021 C402.5.2 & C402.5.3, or project-specific air barrier performance criteria compliance, call 312.897.3742 or e-mail service@hightower-labs.com. With the midwest’s largest CFM capacity and experience in projects widely ranging in volume and complexity, HTL is best equipped to support your project’s energy efficiency verification.


ASTM E779
Standard Test Method for Determining Air Leakage Rate by Fan Pressurization

ASTM E1186
Standard Practices for Air Leakage Site Detection in Building Envelopes and Air Barrier Systems

ASTM E1827
Standard Test Methods for Determining Airtightness of Buildings Using an Orifice Blower Door

ASTM D4541
Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers

ASHRAE 90.1 2016 Testing

ASHRAE 90.1 2019 Testing

IECC Air Barrier Testing

USACE Test Protocol

Water-Resistive Properties
Fenestration | Cladding | Masonry | Flashing

The water-resistive performance of the building envelope is critical for structural integrity (reference nearly every recent catastrophic building collapse), indoor air quality (organic growth formation), humidity/moisture control, component deterioration and rot, etc. HTL has a complete suite of field tests to evaluate a building's water-resistive performance with lab-quality data and comprehensive report deliverables.

Hightower Labs conducting ASTM E1105 field testing for building envelope systems.

AAMA 501.2-15
Quality Assurance and Diagnostic Water Leakage Field Check of Installed Storefronts, Curtain Walls and Sloped Glazing Systems [sic]

AAMA 502-21
Voluntary Specification for Field Testing of Newly Installed Fenestration Products

AAMA 503-14
Voluntary Specification for Field Testing of Newly Installed Storefronts, Curtain Walls and Sloped GLazing Systems [sic]

AAMA 511
Voluntary Guideline for Forensic Water Penetration Testing of Fenestration Products

ASTM E1105
Standard Test Method for Field Determination of Water Penetration of Installed Exterior Windows, Skylights, Doors, and Curtain Walls, by Uniform or Cyclic Static Air Pressure Difference

ASTM E783
Standard Test Method for Field Measurement of Air Leakage Through Installed Exterior Windows and Doors

On-Site Mockup
Save cost and improve awareness of critical system detailing and transitions among on-site personnel. Rather than a remote location with, often times, little involvement from key on-site installers and documentatation of critical detailing/remediation lost in the subsequent reporting - consider an on-site or local "mini-PMU" with participation from all building envelope trades (e.g. block, framing, sheathing, vapor barrier install, rain screen, metal panels, windows, etc.).

Electronic Leak Detection (ELD)

Among HTL's roster of test equipment is the Electronic Leak Detection system compliant with ASTM D7877 - Standard Guide for Electronic Methods for Detecting and Locating Leaks in Waterproof Membranes.

A meticulous and thorough procedure, we can detect voids, tears, slices, and holes in roof and parapet membranes with pinpoint accuracy so that they can be repaired before leaking into the roof assembly. This method can detect even miniscule breaches undetectable to the human eye and overlooked by the often misused thermal camera approach.

Hightower Labs conducting ASTM D7877 field testing for electronic leak detection of roof systems.

Critical step in responsible envelope procurement

HTL provides on- and off-site mockup arrangements at a fraction of the cost for traditional PMU mobilizations. We are local to Chicago and therefore save travel and lodging expense for the project team & installation contractor(s).

In this environment of unreliable test and certification data, skipping the PMU is malpractice.

With HTL's budget-conscious and highly informative PMU offering, there is little reason to accept a VE deduct for pre-mobilization testing ever again.

Hightower Labs conducting air barrier field testing per ASTM E1186.

Hightower Labs, Inc. is an AAMA-accredited field testing agency.

Accurate Measurement of Adhesive Attachment for Installed Materials

Air barrier adhesion can be evaluated under ASTM D4541, where the ultimate force applied at barrier detachmnet is measured and recorded.

For air barrier and EIFS systems where the structural attachment is entirely dependent on adhesive bond, this procedure provides an important evaluation of that structural attachment before the system is buried under rainscreen cladding.

Hightower Labs conducting ASTM D4541 for air barrier adhesion.

NOTEWORTHY FROM HTL

Independent studies, industry papers, slideshows, video presentations, and other content benefiting those in the industry with the patience to read five pages, and diagrams for the developers.

  • Meet the New UI Design
    ASTM E783 AND ALL-GLASS FACADES

    Industry-wide, invalid and improperly executed ASTM E783 test data are not providing a reliably accurate accounting of the building's air-tightness on window wall and curtain wall systems comprising the majority of envelopes built this century and, consequently, building stakeholders are blind to their property's performance.

  • ssg system scale
    SSG ITEMS OF CONCERN

    In this Notes From The Field article, HTL checks in on the U.S. construction industry's widespread use and mis-use of structural glazing systems.

  • Lean
    BEAM03 PROCEDURE INTRODUCTION

    The BEAM03 procedure introduces a novel approach to evaluating building envelope water resistivity, addressing critical gaps in traditional QAQC practices. BEAM03 delivers reliable, repeatable data for assessing large-scale envelope performance, including complex geometries and system transitions.

13
U.S. States Served
72
2-Yr Trailing Avg. Satisfied Clients
1.000
Leak Investigation Batting Avg.
172
Buildings Served