ASTM E2813 and the Owner’s Project Requirements
There are dozens of factors considered in establishing OPR for a given project, including energy consumption, environment, safety, security, durability, and operation. Design aspects of the building enclosure have also evolved dramatically over the past decade—new and improved materials, better understanding of how enclosures perform, updated codes and standards, building information modeling (BIM), and additional project delivery methods (e.g. design-build). Each of these aspects has an impact on the others, which has invariably resulted in a more complex process of how a project unfolds and is ultimately completed.
The majority of large-scale design/construction projects revolve around a single concept known as the owner’s project requirements (OPR). Developed throughout each project phase, these criteria essentially define the performance specifications for the building as a whole.
This increased complexity often means significant time (a valuable resource) in ensuring proper performance test standards are specified, building codes are satisfied, the design is constructible, and, ultimately, OPR is satisfied. The recently published ASTM E2813, Standard Practice for Building Enclosure Commissioning, provides the architect of record (AOR) a single-source guideline for establishing OPR and providing a clear pathway to accomplishing each project phase to satisfy the requirements related to the building enclosure (Figure 1).ASTM E2813 is essentially a vehicle for combining existing requirements from dozens of test standards covering several building enclosure elements, as well as American Society of Heating, Refrigerating, and Air-conditioning Engineers (ASHRAE) Guideline 0, The Commissioning Process, and National Institute of Building Sciences (NIBS) Guideline 3, Building Enclosure Commissioning Process. Similarly, the various design, performance, and operational requirements covering the elements comprising the building enclosure can be combined into a single specification section that references ASTM E2813. In fact, Section 01 91 19.43–Exterior Enclosure Commissioning has been included in MasterFormat since at least the 2004 edition, but has yet to be implemented on a widespread basis. The AOR can now simply reference one section that includes such references in the individual specification sections.
A building enclosure commissioning (BECx) process to ensure high performance provides myriad benefits to the owner, AOR, and contractor (similar to the processes by which mechanical, electrical, and plumbing systems are commissioned to verify compliance with OPR). Benefits of BECx include:
- building enclosure-related OPR is clearly established and conveyed throughout each project phase;
- a single-source reference for dozens of performance testing requirements simplifies the specification writing (and interpreting) process;
- better planning and proactive design considerations in the pre-design and design phases reduce confusion, Requests for Information (RFIs), change orders, and improper or inadequate deliverables in the construction phase;
- supplements to contractor’s quality control (QC) program via third-party quality assurance observations and construction checklists reduce the potential for construction defects;
- testing and verification of building enclosure performance characteristics result in proven performance before building turnover and decreased operating costs via less energy consumption (Figure 2); and
- routine inspection and maintenance plans produced as part of project close-out provide guidance to building owner/occupants.
As mentioned, current traditional systems requiring commissioning include mechanical, electrical, and plumbing. While these systems have evolved in their function and complexity, so have the elements of the building enclosure. In the authors’ interactions with clients and colleagues across the country, there has been as steady increase in attention to BECx and requirements included in project specifications. At this point, government and institutional facilities appear to be leading the charge for these requirements, but the private sector is steadily falling in line. There are multiple scenarios as to how the BECxA is integrated within the project—ultimately, the OPR would establish the function and relationship of the BECxA with the team.
Establishing the OPR and Levels of BECx
The newly created ASTM E2813 Annex A1, “OPR Development Guideline,” outlines the establishment of the owner’s project requirements in consideration of energy, environment, safety, security, durability, sustainability, and operation. This guideline is a prescriptive method that includes a series of questions representing “the minimum range of issues and concerns that must be considered under this practice during the development of the OPR to determine the level of commissioning and functional performance testing.” These queries cover general building characteristics, including:
- use and occupancy classification;
- construction type;
- anticipated service life;
- geographic location;
- energy performance requirements;
- project delivery method; and
- budget considerations for BECx activities and the overall project.
From this process, the owner, AOR, building enclosure commissioning agent (BECxA), and commissioning agent (CxA) create a scope of consulting and testing services.
ASTM E2813 establishes two levels of building enclosure commissioning: fundamental and enhanced. These levels are similar in terms of the BECxA’s role, and both are defined as architecture/engineering-related technical services performed on the owner’s behalf. In fundamental BECx:
- BECxA becomes involved in the project no later than the design development phase;
- preliminary OPR is reviewed and documented;
- there is a single design review of enclosure-related drawings and specifications; and
- limited number of lab and field performance tests are required, including:
– American Architectural Manufacturers Association (AAMA) 501.2-2009, Quality Assurance and Diagnostic Water Leakage Field Check of Installed Storefronts, Curtain Walls, and Sloped Glazing Systems;
– ASTM E783, Standard Test Method for Field Measurement of Air Leakage Through Installed Exterior Windows and Doors; and
– 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.
In enhanced BECx:
- BECxA is involved in the project no later than commencement of the schematic design phase;
- technical assistance and documentation are provided for development of preliminary OPR;
- at least three design reviews of enclosure-related drawings and specifications are accomplished; and
- additional lab and field performance tests are conducted beyond those in the fundamental process—examples include:
– ASTM E966, Standard Guide for Field Measurements of Airborne Sound Insulation of Building Facades and Façade Elements;
– ASTM E779, Standard Test Method for Determining Air Leakage Rate by Fan Pressurization; and
– AAMA 501.1, Standard Test Method for Water Penetration of Windows, Curtain Walls, and Doors Using Dynamic Pressure.
Successful commissioning of the building enclosure requires specific areas of expertise and experience in areas generally outside the capabilities of most mechanical/electrical/plumbing (MEP) commissioning firms. ASTM E2813 recognizes the need for qualified BECx firms, and the standard therefore requires agents to demonstrate a level of proficiency in the following building and materials science areas:
- enclosure-related materials, components, systems, and assemblies (with respect to durability, serviceability, interaction with other building elements, and performance characteristics);
- heat transfer;
- air infiltration/exfiltration (Figure 3); and
- moisture storage, transport, and diffusion.
While ASTM E2813 does not provide strict guidelines for what constitutes the “level of proficiency” in each of these core competencies, caution should be taken when selecting potential BECxA firms. Those companies with years of project experience in the core competencies generally possess the knowledge and abilities to contribute to a successful project. Potential BECx firms should be carefully vetted as part of the selection process to ensure a successful installation and performance of building components that are arguably the highest risk area of design and construction.
ASTM E2813 outlines a BECx process similar to those described in ASHRAE 0 and NIBS Guideline 3, and defines it in each of the project phases. The roles and responsibilities of the BECxA evolve as the project progresses; close communication with the owner, AOR, and general contractor is paramount to the commissioning agent’s successful integration with the project team. Depending on various factors, including the contract delivery method and OPR, the BECxA could be positioned in several locations within the project team. Possible scenarios are show in Figure 4.The BECxA could be part of various enclosure commissioning activities for both fundamental and enhanced routes, depending on the required level of involvement. With the exception of the aforementioned key differences, the services provided in both processes are nearly identical. They include:
- provide technical assistance to owner and AOR to develop written OPR for the enclosure;
- evaluate durability, serviceability, performance, and sustainability of various types of enclosure elements;
- target key elements related to the building enclosure to be incorporated into the design documents (e.g. below-grade waterproofing, WRBs, air barriers, vapor retarders, claddings, and roof assemblies);
- attend project planning/kickoff meetings to discuss the building enclosure system, review OPR, and ensure its consistency with Basis of Design (BOD) for the project; and
– submit a preliminary plan defining:
– scope and budget of commissioning activities;
– BECxA roles and responsibilities; and
– how BECxA relates to the owner, AOR, project manager, contractor, and commissioning agents.
- develop BECx specification to be included in the construction documents;
- review enclosure-related design documents (quantity and timing dependent on whether the commissioning is fundamental or enhanced);
- establish quantifiable test standards and performance metrics to be included in the CDs, including protocol for required additional testing due to test failures;
- evaluate performance of untested or questionable assemblies via thermal and vapor flow analysis (Figure 5); and
- document advantages, disadvantages, and summary discussion of related design decisions adopted by AOR during design phase.
- assist, as required, owner/AOR in the bidding and award process;
- attend pre-bid conference and evaluate bidder RFIs;
- aid in the development of addenda related to building enclosure-related RFIs (this ensures information included is consistent with OPR); and
- document, after bid awarded, pre-construction-phase OPR, enclosure BOD, and revised BECx plan for owner review and approval.
- review enclosure-related shop drawings and technical submittals to ensure compliance with OPR;
- participate in pre-installation meetings related to the building enclosure;
- develop site observation and documentation protocols requiring timely identification and remediation of unanticipated field conditions;
- observe progress of enclosure-related work and provide reports for site visits;
- attend BECx meetings with the general contractor/AOR/owner;
- maintain documentation on performance testing milestones; and
- develop BECx closeout documents.
Occupancy and Operations Phase
- meet with owner and building representatives to discuss project history and current open items, as well as an evaluation and maintenance schedule; and
- provide owner and building representatives with a routine evaluation and maintenance schedule that aims to preserve the enclosure’s as-built durability and performance.
BECx Performance Testing Requirements
Table A2.1 in ASTM E2813 Annex 2 includes a comprehensive list of BECx performance testing requirements. Approximately 90 test standards are listed, including those from:
- American National Standards Institute (ANSI);
- Glass Association of North America (GANA);
- Canadian Standards Association (CSA);
- National Fenestration Rating Council (NFRC);
- Underwriters Laboratories (UL); and
- U.S. General Services Administration (GSA).
- acoustic performance;
- air and water leakage;
- thermal performance and condensation resistance;
- structural performance; and
The latter columns in table A2.1 designate whether each test is optional or mandatory, and mockup or in-situ. In considering whether tests are actually ‘mandatory,’ it is worth discussion with the owner and AOR whether these requirements would lend to satisfying the OPR for the specific project.
Applying the Standard to Projects
Located in Fort Hood, Texas, the new Carl R. Darnall Army Medical Center project includes the design and construction of an 87,980-m2 (947,000-sf), $534-million facility consisting of a six-story hospital, three out-patient clinic buildings, and three parking garages. It will replace the adjacent original 55,740-m2 (600,000-sf) Darnall Hospital (Figure 6).
The hospital serves roughly 45,000 soldiers, as well as nearly 125,000 family members and retirees. An important feature of the new hospital is the approximately 9290-m2 (100,000-sf) clinic dedicated to behavioral health services, which provides mental and physical care for soldiers. The BECx services provided are listed in Figure 7.
There is no doubt there is a growing movement in the construction field toward building enclosure commissioning. The individual components have been around for years, but it seems this most recent push forward by ASTM to compile them into a single standard simplifies the effort necessary to incorporate high-performance building enclosure design into construction specifications.
Merely referencing an ASTM standard in a specification might not convey the design intent for building enclosure. As with any specification, it should be fully developed to clearly identify the qualifications of the BECxA and define project-specific procedures in Part 3.
Stuart Mitchell, PE, is a project manager in the Building Science Group at Pie Consulting and Engineering. He is responsible for design development assistance, plan/specification peer review, and quality assurance field observations related to water management systems, air barriers, vapor retarders, and thermal insulation. Mitchell is involved in field performance testing and diagnostic evaluations of fenestration, curtain walls, and claddings, as well as whole building air barrier testing. He has extensive experience in the development of rehabilitative design documents and project management. Mitchell can be contacted at firstname.lastname@example.org.
Jeff Crowe, MS, EI, is a senior building science specialist in Pie’s Building Science Group. His responsibilities include design development assistance, plan and specification reviews, quality assurance field observations, building performance testing, and diagnostics on both new and rehabilitation construction projects. Crowe has also served as a restoration and design engineer for a specialty engineering firm, providing design and consulting services for the construction and rehabilitation of concrete parking structures across the United States. He can be reached at email@example.com.
Article was originally published February 1, 2012 in The Construction Specifier.