Attachments -A-C ENAPROC QA REP.pdf

ATTACHMENT A

DEPARTMENT OF THE ARMY EP 415-1-261

U.S. Army Corps of Engineers Volume 6

CECW-CE Washington, DC 20314-1000

Pamphlet No. 415-1-261 21 April 2016

Construction

QUALITY ASSURANCE REPRESENTATIVE’S GUIDE

VOLUME 6: BUILDING ENVELOPES

FOREWORD

1. Purpose.

a. The purpose of this Engineer Pamphlet (EP) is to provide guidance on the inspection and quality assurance process for the construction of key components of building envelopes to ensure performance standards (e.g., references a and b) are met.

b. The performance of our buildings can be quantified by how well they protect the interior from the exterior environmental conditions. Specifically, how well they limit the intrusion of air, heat, and water (as both liquid and vapor). Both designers and constructors should be keenly aware of how the building assemblies control each of these elements, ensuring that the controlling layers are continuous to form a complete envelope wrapping all six sides of the interior space. Careful consideration must be given as to how each of these layers of the envelope is sequentially constructed to ensure performance continuity through all corners and material transitions.

c. In reviews of many high performance buildings, we have found strategies that can be employed during the project construction phase to ensure building envelopes have been appropriately detailed, constructed, and tested to assure high performance. The attached guide serves as a reference manual for construction activities to ensure the quality and functional requirements of High Performance Building Envelopes are met.

2. Applicability.

a. This guidance applies to Headquarters, U.S. Army Corps of Engineers (HQUSACE) and all Office of the Chief of Engineers (OCE) elements, major subordinate commands (MSC), district commands, laboratories, and field operating activities (FOA). This document adds a sixth volume to EP 415-1-261 (reference c). Certain components of the building envelope which are addressed in this document are critical to overall building performance. To achieve the intended building performance, Quality Assurance (QA) plans will need to address the following, as applicable:

(1) General Overview and Three Phase Control Process

EP 415-1-261 VOL 6

21 Apr 2016

(2) Exterior Cladding

(3) Roof Coverings

(4) Fenestration

(5) Thermal Bridges

(6) Thermal Envelope and Insulation

(7) Air, Vapor and Water Control Layers

(8) Water Drainage

(9) Wall Types

(10) Air Leakage Test Protocol

(11) Air Leakage Specification

(12) Reporting of Test Results

3. Distribution Statement.

a. This Engineering Pamphlet is approved for public release; distribution is unlimited.

b. Electronic copies of this and other United States Army Corps of Engineers publications are available at http://www.publications.usace.army.mil/. This site is a repository for all USACE engineer regulations, circulars, manuals, and other documents originating from

HQUSACE.

4. References.

a. Unified Facilities Criteria (UFC) 1-200-02, 1 Mar 2013, Subject: High Performance and Sustainable Building Requirements

b. Unified Facilities Criteria (UFC) 3-101-01, 28 Nov 2011, Subject: Architecture

c. Engineer Pamphlet (EP) 415-1-261, 1 Aug 1992, Subject: Quality Assurance Representative’s Guide series, Volumes 1 through 5

5. General.

a. Quality Assurance/Quality Control (QA/QC) representatives will find the information provided in this guide useful during the performance of their duties of assuring and controlling construction quality in accordance with the plans and specifications. The guide will, therefore, become a valuable reference when implementing project plans and specifications.

EP 415-1-261VOL6

21Apr2016

b. The contents will also help refresh the memory of experience, training, and good common sense. The application of sound knowledge together with a proper sense of responsibility and use of authority will result in meaningful decision making, a factor considered essential for effective quality assurance/quality control.

FOR THE COMMANDER:

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D. PETER HELMLINGER

COL, EN

Chief of Staff

THIS PAGE INTENTIONALLY LEFT BLANK

EP 415-1-261

Volume 6

21 April 2016

Quality Assurance

Representative’s Guide

Volume 6:

Building Envelopes

Approved for Public Release. Distribution is Unlimited

Published by:

Headquarters, US Army Corps of Engineers

Engineering & Construction Division

441 G Street NW

Washington, DC 20314

Point of Contact:

Eric Mucklow, AIA eric.s.mucklow.civ@mail.mil

Approved for Public Release

Distribution: Unlimited

EP 415-1-216 VOL 6

CONTENTS

CHAPTER 1

1-1. General Overview

1-2. Three Phase Control Process

CHAPTER 2

2-1. Definitions

2-2. Materials

2-3. Applications

2-4. QA activities

CHAPTER 3

3-1. Definitions

3-2. Materials

3-3. Applications

3-4. QA activities

CHAPTER 4

4-1. Definitions

4-2. Materials

4-3. Applications

4-4. QA activities

CHAPTER 5

5-1. Definitions

5-2. Materials

5-3. Applications

5-4. QA activities

CHAPTER 6

i

6-1. Definitions

6-2. Materials

6-3. Applications:

6-4. QA activities

CHAPTER 7

7-1. Definitions:

7-2. Materials:

7-3. Applications:

7-4. QA Activities

CHAPTER 8

8-1. Definitions

8-2. Materials

8-3. Applications

8-4. QA activities

CHAPTER 9

9-1. Overview

9-2. Insulated Concrete Forms (ICF)

9-3. Cold Formed Steel (CFS) Framing

9-4. Concrete Masonry Units (CMU)

9-5. Autoclaved Aerated Concrete (AAC)

9-6. Tilt-up and Pre-Cast Concrete Panels

CHAPTER 10

10-1. Building Air Tightness Requirement

10-2. Performance Requirement and Substantiation

10-3. Specifier and Witness Guidance. Application and Scope ii

10-4. Defining the Test Boundary

10-5. Whole Building Testing

10-6. Individual Room or Dwelling Testing

10-7. Test Spaces Contained within Larger Zones

10-8. Larger Buildings

CHAPTER 11

11-1. General

CHAPTER 12

12-1. U.S. Army Corps of Engineers (USACE) Standard for Air Leakage

12-2. Application and Scope

12-3. Test Equipment Air flow Capacity

12-4. Building Envelope Pressure Measurement

12-5. Interior Pressure Uniformity

12-6. Pre-Test Inspection and Equipment Check

12-7. Before Starting the Test

12-8. Performing the Test

12-9. Reporting of Results

12-10. Locating Leakage Sites with Pressurization and Depressurization

12-11. Thermography Requirements

12-12. Infrared Imaging System Calibration

12-13. Infrared Imaging System Specifications

Glossary and Acronyms

Envelope Testing Process Quick Reference iii iv

CHAPTER 1

General Overview and the Three Phase Control Process

1-1. General Overview.

Due to the complexity and variability of the building envelopes in construction, coupled with the variation in functions of Military and Civil Works vertical construction projects and the requirements associated with them, this Guide will attempt to canvas the most pertinent Quality Assurance related aspects of a High Performance Building Envelope in Military and Civil works construction and give the Quality Assurance Representative a foundation from which to ensure that the building envelope will meet the specified performance expectations required of it. The aspects covered in this guide are applicable to new vertical construction as well as renovation and retrofit construction projects.

1-2. Three Phase Control Process.

a. Preparatory Phase

(1) Drawings and Specifications

(a) During the Preparatory phase meeting the QAR should ensure that the contractor and subcontractors have the most current sets of the contract drawings and specifications.

(b) Drawings and specifications should be thoroughly reviewed and discussed with all the applicable trades or craftsmen involved in the vertical construction of the building envelope.

(2) Submittals

(a) Material Submittals

Submittals should be reviewed for contract compliance as well as compliance to the Buy American Act. All submittals for either DOR approval or government approval should be approved before this phase of the three phase process. All applicable submittals should be present for the Preparatory meeting for review and discussion.

Each material or assembly as stated above will have specific manufacture’s installation instructions and performance criteria. The QAR should be looking to these documents to ensure that the contractor or subcontractor is installing or applying these materials properly and within the application or installation parameters. Many of these materials come from a manufacturer as systems of components. For best results, it is recommended that the materials be consistent from a manufacturer if possible.

(3) Shop Drawings

(a) The QAR ensures that all shop drawings for assemblies such as curtain wall, windows, doors, store front assemblies, roof systems or other envelope specific components interface with the air barrier and/or other control layers and that continuity is maintained between fenestration and systems.

(b) Changes to specific assemblies identified for thermal bridge reduction in the contract drawings by shop drawings may be to the detriment of the design for this assembly. Due to the specifically designed nature of thermal bridges, deviations from a detail of this nature could result in the failure to reduce the thermal bridge. Any changes to the design must be validated by the DOR before construction begins. The QAR should always involve the Contracting Officer or Contracting Officers Representative before changes are made to the design of the assembly.

(4) Schedule/Sequence

(a) The schedule and sequence of construction of the various features of the building envelope may occur at different times throughout the life of the project. Proper sequence and coordination entail ensuring that the substrates are complete, ready to accept or have installed the control layer, insulation fenestration or roof assembly and are free of any material that would damage or alter the material or assembly and its dedicated function once in place. Coordination with the trades should be discussed and those specific aspects of the other features of work that will interface with the various building envelope components are complete or in their final location prior to the follow on feature being constructed.

(b) The QAR should ensure that the contractor is at a point in the construction that will facilitate the proper construction of the building envelope feature, component or assembly. The QAR should be aware of the assemblies and the details of the construction feature to ensure that proper sequence is maintained. This should be discussed with all contractors, subcontractors and trades prior to work beginning.

(c) Out of sequence work with regard to control layers, fenestrations, thermal insulation or roof assemblies can adversely affect the installation and performance of the various envelope components or features and the performance of the envelope as a whole. Out of sequence work can also lead to inadvertent changes in the construction of the assembly that may be detrimental to the function of the building envelope.

(5) Mock-ups

(a) The QAR should be familiar with the requirements for a mock-up of the prescribed assemblies in the specifications and ensure that the contractor is aware of these requirements also.

(b) An individual three phase process with all of the associated craft related to the construction of the mock-up may be needed to ensure that the mock-up is properly constructed and all features are represented as specified.

(6) Testing

(a) The QAR should ensure that any material or system related testing is discussed and identified as well as the time frame in which the testing is to occur. Testing entities or individuals competent to perform testing should be present for coordination and expectation purposes.

(b) The QAR should ensure that the contractor or subcontractors are aware of any and all testing requirements for the materials and systems. Qualifications for testing if applicable should be identified at this time.

(7) Discrepancies or Changes

b. The QAR should be made aware of any discrepancies or changes associated to the work prior to the work being started or completed. The QAR should document these all discrepancies or changes as well as the contractor. Depending on contract type the changes should flow through the RFI channels to the DOR to ensure that changes will not adversely affect the quality, performance and scope of the work in question. The Contracting Officer, Administrative Contracting Officer or Contracting Officers Representative should be involved with any changes that are made to ensure contract compliance.

c. Materials Inspection

(1) All materials or assemblies must be inspected for compliance to the submittals prior to their incorporation into the initial representative sample of work. Contract requirements such as compliance to the Buy American Act should be addressed before the work has started to prevent or identify any non-compliant or non-specified materials.

d. Initial Phase

(1) Upon determination of the time and date for the initial inspection as well as establishing that a representative sample of work has been completed, the QAR, QCM and all associated trades and craftsmen should be present to inspect the work. Any manufacturer representatives or third party entities identified by the specifications or deemed necessary should also be present during this phase.

(2) Primary inspection points as listed in this guide, plus any site specific conditions that may exist should be inspected for contract compliance. Means and methods should be assessed to ensure that subsequent work will remain compliant, which should include any manufacturer recommendations or parameters specific to the building envelope feature or component being inspected.

(3) Should the QAR or QCM during the initial inspection process identify deficiencies, these issues should be documented and with the installation or application craft present, the issue should be addressed in the appropriate manner.

(4) If an impasse is reached and a deficiency or issue cannot be addressed simply through the means and methods of the contractor for a component of the feature of work, the referenced standards, manufacture product data or involvement of the manufacturer and /or DOR may need to be sought to correct the issue.

(5) Follow on work for the feature or component of the building envelope shall not continue until all deficiencies are corrected.

e. Follow-up Phase

(1) In the Follow-up phase the QAR should be verifying that the work is proceeding in a consistent manner as determined in the initial phase.

(2) Follow-up inspections should be performed throughout the duration of the installation or application of the building envelope feature or component. At any point during the installation or application should an issue arise the prime contractor QCM should be contacted and a Follow-up inspection held. If a deficiency is identified the issue should be documented by both the QAR and the QCM and the corrections made before any further work continues.

CHAPTER 2

Exterior Cladding

2-1. Definitions.

a. Exterior claddings are the non-load bearing outer skins of a building, forming the exterior finish surface. The exterior claddings defined in this section fall into the following moisture control types, giving the cladding different functions within the building envelope:

b. Drain screen - back-ventilated exterior cladding that allows moisture to infiltrate and escape, with a pressure moderated vertical airspace that is drained to the exterior using the environmental control layer. The air space can be vented or unvented. This system relies on deflection, drainage, and drying.

c. Rainscreen - exterior cladding system that sits away from the environmental control layer, incorporating a pressure-equalized drained compartmentalized cavity behind the skin to control the amount of water that comes into contact with the environmental control layer. The components reduce the pressure across the rainscreen by equalizing the cavity pressures with the exterior wind pressures.

d. Face Seal - relies on tightly sealed joints to resist air and water leakage. QA is very important since workmanship becomes critical. Insulated metal panel systems also fall into this category of cladding systems.

2-2. Materials.

a. Numerous exterior cladding materials are available for commercial type construction.

The different materials can be classified by moisture control types:

(1) Drain screen: Drain screen systems come in a variety of forms and materials each having unique properties, but all allowing the escape of moisture.

(2) Brick, stone or CMU veneer cavity walls

(3) Cement board, vinyl or wood siding

(4) Exterior Insulation and Finish Systems (EIFS)

(5) Stucco

b. Rainscreen: Pressure equalized rainscreens are typically an engineered metal assembly.

(1) Metal panel sheets

(2) Curtain walls

c. Face Seal: Face seal systems can vary in forms and materials, but all are intended for the skin and joints to resist water and air leakage.

(1) Insulated metal panels

(2) Field-applied coatings (epoxy)

2-3. Applications.

a. In the installation of the exterior cladding onto a building, it is important for the QAR to understand the moisture control types of the exterior cladding, so appropriate quality control can be given to the correct layer to maintain water-tightness and perform the intended function.

b. Continuity: the water resistant layer must be continuous, regardless of where in the assembly the layer sits. The importance of the QAR identifying the water resistant layer and confirming the integrity of its installation is paramount.

c. It is critical that the contractor fully understands the interfacing at transition points between roof assembly and wall assembly as well as around penetrations and fenestrations.

2-4. QA activities.

a. Level of QA and activities depends heavily on the moisture control typology of the cladding type.

(1) Preparatory Phase

(a) Contract Document Review

Drawings and Specifications

Design of wall assembly: The QAR should understand the moisture control typology of the exterior cladding and locate where the water resistant layer sits within the assembly, which will vary by wall type. Note whether the water resistant layer has other functions, such as air barrier or vapor barrier, and what the requirements are for those intended functions.

Detail Drawings: The QAR should conduct a thorough review of construction details, especially where numerous trades are involved. The QAR should locate transition points where different wall types abut and be familiar with the transition details.

Material Specifications: There should be continuity between that materials identified in the drawing sheets and specifications. The QAR should review moisture control requirements and determine where the critical moisture control points are. The QAR should verify contract document requirements for mock-ups.

(2) Submittals

(a) Qualifications: The QAR should check that the qualifications of the installer meets the requirements in the Installer’s Qualifications paragraph of the contract

(b) Shop Drawings: The QAR should cross reference the shop drawings for the exterior cladding with shop drawings for other systems and components that interface with the exterior cladding, such as the other components within the wall assembly, door/window frames, or sunshades.

(c) Product Literature

The QAR should verify the Solar Reflectance Index (SRI) of the cladding meets the contract requirements. SRI is carefully considered in the design of the envelope, and substitutions should not just be reviewed for color match but also the salient characteristics.

(d) Manufacturer’s Recommended Installation Instructions

The QAR should review contract and manufacturer’s installation instructions to see if special processes are required during particular weather conditions. Weather conditions may affect thermal expansion/ contraction of the system, or drying/curing of the material.

The QAR should ensure substrates are properly prepared in accordance with manufacturer’s instructions.

(3) Schedule and Sequence

(a) Prior to exterior cladding construction beginning, all preceding work on the exterior envelope, such as control layers and flashings, that will be covered must be inspected and complete.

(b) Sequence of installation is critical to ensure that incomplete work is not covered by the exterior cladding and becomes inaccessible.

(c) All tests or inspections that may be specified to be performed should be complete prior to cladding construction.

(d) Environmental conditions should be suitable for the installation or construction of the cladding, specifically masonry claddings.

(4) Mock-up

(a) Water Intrusion Testing: The QAR should ensure that the water spray test is done in accordance with contract requirements.

(b) Material compatibility- The QAR should check the compatibility of fasteners and anchors to main material and substrate, separation of incompatible components should be made if necessary such as dissimilar metals.

(c) The QAR should review sequencing of trades for all systems and components interfacing with the exterior cladding.

(5) Testing

(a) The QAR should be aware of all testing that may be specified for a given cladding type. These tests and the responsible party should fully review and discuss the process and procedure to ensure testing is complete and accurate.

(b) For masonry claddings, testing for mortar or grouts must be performed by a testing laboratory qualified to perform the tests.

(6) Discrepancies or Changes

(a) Should the QAR discover or be made aware of a change or discrepancy with a cladding assembly, component or the general installation of the cladding, this change should be carefully evaluated before work proceeds. Any changes that alter the design of the cladding assembly must be evaluated with the COR, ACO or CO and the DOR to ensure contract compliance.

b. Initial Phase

(1) Materials Inspection

(a) All materials should be inspected prior to the incorporation into the permanent work.

(b) During the material inspection, it is critical that the colors and types of materials that will be used in the exterior cladding are compliant with the contract and submittals.

(2) Inspection of Work

(a) The QAR should note primary inspection points and any site specific conditions.

(b) Level of Workmanship: Must meet contract requirements as well as manufacturer’s requirements.

(c) Fasteners and Thermal Bridges: See section on thermal bridges. The QAR should ensure that there are no unintentional or unnecessary thermal bridges caused by fasteners or other connections. The QAR should pay special attention to fastener requirements, especially requirements for gaskets or seals that interface to control layers.

(d) Sealant locations: The QAR should confirm that sealant is continuous where specified, paying critical attention where the sealant is used on the water resistant layer.

(e) Terminations and transitions: The QAR should inspect the material transitions of the exterior cladding to ensure no disruption of the water resistivity.

(3) Special Considerations by Moisture Control Type

(a) Drain Screen: The QAR should ensure continuity and integrity of the environmental control layer located behind the air space. This is the layer responsible for keeping moisture outside of the wall assembly. Moisture is expected to infiltrate the exterior cladding finish material.

(b) Rainscreen: The QAR should ensure engineered cladding system is installed per manufacturer’s recommendations and instructions. This system is critical to drain water away from the wall assembly

(c) Face Seal: If the system relies on a tightly sealed joints and transitions to form the face seal, The QAR should pay special critical attention to the continuity of the sealant in the assembly.

c. Follow-up Phase

(1) The QAR should verify that work is proceeding in a consistent manner, paying close attention to site-specific critical inspection points:

(a) Thermal bridge locations

(b) Wall to floor slab/ foundation transition

(c) Drainage plane

(d) Fenestrations and penetrations

(e) Material transitions

(f) Joints: material joints, control joints

(g) Fasteners (gaskets and seals)

(h) Wall to roof transition

(i) Thru-wall flashing

(2) The QAR should monitor installation temperatures and weather conditions if required, ensuring that the installation is within the manufacturer’s recommended conditions.

d. Construction Installation Means/Methods

(1) Means and methods for installation and construction of the exterior cladding should be appropriate given the dimensions of the building.

(2) Often scaffolding of various types is used as the means of access to the work area. All scaffolding safety measures as required by the EM 385-1-1 must be addressed before work can proceed and continually monitored for compliance once work is underway.

(3) Depending on local climate, means should be provided to protect the work in adverse weather conditions to prevent detriment to the cladding. Product manufacturers will identify the parameters required for performance of their products and these parameters should be followed.

(4) For masonry, brick or block claddings special techniques may need to be employed by the masons placing mortar to prevent significant spillage of mortar droppings into the air space of a cavity wall. This could be the use of a drag board or the modification of the mortar placement technique to prevent spillage.

e. Inspection Points

(1) Local climate and environmental conditions play a significant role in the favorable installation of various claddings. The QAR should assure that the contractor is providing adequate means of environmental control to allow for the proper construction and use of materials in the cladding if adverse weather conditions are present.

(2) Materials should be stored away from potential damage from equipment of other construction activities. Materials should be kept in a location that will protect them from any environmental deterioration or damage prior to construction.

(3) In masonry construction, block or brick joints should be fully bedded. Air space in a cavity wall should be free of mortar droppings.

(4) Block or bricks that appear to be disintegrating are brittle and break easily or are significantly cracked should not be used and should be removed from the site.

(5) Mortar or grout joints should be free of holes, gaps or improperly filled sections.

(6) In EFIS systems, substrates must be free from dust dirt and debris. Reinforcing substrate or application of the exterior finish material must be fully adhered to the substrate.

Gaps, bubbles or space in these locations must be avoided.

(7) The QAR should evaluate masonry materials for color and type before work is initiated to assure proper materials are on site.

(8) Control or expansion joints should be free of mortar or other debris and the correct width as shown in the drawings or as specified.

(9) Brick ties, clips or fasteners should be the correct type. These components should properly interface with any control layers present and should be gasketed or sealed to prevent air, water and vapor intrusion.

(10) Thru wall flashings should be sealed and in place prior to the cladding installation or construction and should be properly interfaced with the control layer.

(11) All penetrations and fenestrations will need to be sealed. The QAR should assure that adequate dimension is present for the placement of seals and sealant materials in the building envelope. These seals may or may not interface directly with the cladding depending on design and materials involved.

(12) Dimension should be verified by the QAR to assure that claddings, once installed will not impede the placement of fenestrations into the wall assembly.

(13) The QAR should assure that the contractor has identified all penetrations prior to the construction or installation of the cladding to ensure that proper sealing, control layer interface and location are correct.

(14) In metal claddings, materials should be free of scratches, dents or other damage.

(15) All joints in metal claddings should be fully sealed and the sealant color in accordance with that specified in the contract documents.

(16) The QAR should be inspecting for any cracking that develops in masonry claddings.

This could indicate a failure or unexpected movement and this should be fully documented and relayed to the DOR for evaluation.

(17) Cracking in EFIS systems should be inspected for by the QAR as this may indicate improper application mixing, batching or unexpected movement in the wall assembly

(18) The QAR should ensure careful protection of finished surfaces and repair of damaged surfaces. This is extremely critical in assemblies where the exterior cladding functions also as the water drainage or water resistant layer.

f. Special Inspections and Testing

(1) The QAR should ensure that all field tests are done as required in the contract and by the manufacturer and are conducted by a qualified representative. Note if any field tests are required from independent testing agencies.

(2) Testing such as sealant adhesion testing, mortar, grout or stucco mixing and batching and mortar or grout strength testing should all be performed by a qualified entity as specified.

(3) Water penetration testing or other building envelope commissioning tests (BECx) should be performed in the presence of the QAR to assure that the assembly meets the desired performance requirements.

g. Documentation

(1) The QAR should document any field inspection activities performed to include testing, daily inspection, or the three phase inspection process performed for this feature in the daily report for the project.

(2) The QAR should collect any manufacturer site visits or inspection notes during the construction process from the QCM and document these in the contract file.

(3) The QAR should take photos of the work periodically and photographically document any deficiencies found during the inspection process.

(4) The QAR should collect or have submitted all exterior cladding related test reports from the QCM and document them in the contract file.

CHAPTER 3

Roof Coverings

3-1. Definitions.

a. Roof covering refers to the outermost layer of the roof assembly. The roof coverings defined in this section fall under the following installations:

(1) Steep slope- a roof in which the uppermost part is installed at a slope of 2:12 or more.

(2) Low slope- a roof in which the uppermost part is installed at a slope of less than 2:12.

Figure 1. – Left is an example of a fully adhered TPO membrane roof system. On the right, a standing seam metal roofing system.

3-2. Materials.

a. Steep slope: Steep slope roofs shed water towards the eaves and typically utilize the lapping of the roof covering to keep moisture out of the assembly.

(1) Standing Seam Metal Roof panels

(2) Asphalt Shingles

(3) Tile, clay or concrete

b. Low slope: Low slope roofs are weatherproof membranes, requiring different materials than steep slope roofs, and tend to pool water instead of shedding water quickly.

(1) Asphalt Built-up roof membranes

(2) Modified bituminous membranes

(3) EPDM (fully-adhered or ballasted)

(4) Thermoplastic Polyolefin (TPO)

3-3. Applications.

It is important for the QAR to understand the intended design and behavior of the roof materials, to ensure proper installation.

a. Continuity of Watertight Surface: The QAR should check for continuity especially at inspection points listed below for the various roof system types.

b. Thermal Movement: Roof material needs to be installed appropriately for the designed thermal expansion and contraction of the system. The QAR should be familiar with the requirements of the designed system, since some systems need to be installed at a mid-temperature range.

3-4. QA activities.

QA level and activities depend on the roof covering type and slope.

a. Preparatory Phase

(1) Contract Document Review

(a) Drawings and Specifications

Detail drawings: The QAR should conduct a thorough review of construction details, especially where numerous trades are involved. The QAR should be familiar with all roof plane transition details and give special attention to the critical potential water intrusion points such as penetrations, roof curbs and hatches and at the wall to roof interface locations.

Specifications: There should be continuity between the materials identified in the drawing sheets and specifications. The QAR should review moisture control requirements and determine where the critical moisture control points are such as flashings, fenestrations, roof drains and scuppers.

(2) Submittals

(a) Material Submittals

Product literature

The QAR should verify the Solar Reflectance Index (SRI), Solar Reflectance, and Thermal Emissivity of the roof covering meets the contract requirements. SRI is carefully considered in the design of the envelope, and substitutions should not just be reviewed for color match but also the salient characteristics.

Manufacturer’s Recommended Installation Instructions

The QAR should review contract and manufacturer’s installation instructions to see if there is a required installation temperature range or special requirements for excessive temperature or weather installations.

The QAR should not permit the contractor to make any substitutions to a warrantable roof system without the DOR, manufacturer and CO, ACO or COR approval or evaluation. Such substitutions may invalidate the warranty of the assembly.

(b) Shop drawings:

The QAR should cross reference the shop drawings for the roof assembly with shop drawings for other systems and components that interface with the roof covering, such as skylights and roof equipment.

The QAR should verify that the proposed material lengths meet contract requirements.

If applicable, contract language will often require the longest possible continuous lengths of roof covering material, in order to minimize joints and reduce water intrusion. If this is a contract requirement, the QAR should verify these unbroken continuous lengths are reflected in contractor submittals.

The QAR should verify that all structural calculations have been submitted and approved for the roof structure.

(3) Schedule and Sequence

(a) It is critical that all preceding structural work is complete and has been fully inspected prior to the construction of the roofing system.

(b) Environmental conditions must be accounted for during roof system construction to prevent failure of the materials or system due to improper installation parameters or damage to materials.

(c) It is critical that all manufacturers required inspections of the roofing system be thoroughly reviewed discussed and understood prior to work beginning.

(d) Preceding and successive work for other features of the building that may penetrate the roofing system must be accounted for prior to the installation of the roofing system.

(e) Wall system control layers must be in a condition to or complete in order to make the proper interface with the roofing system.

(4) Mock-ups

(a) If specified, all roofing system mock-up should be complete and inspected and evaluated prior to the construction of the permanent work.

(b) Mock-up assemblies should be inspected for proper transition of the water tight layer of the roof to the wall control layers.

(c) If necessary the roofing system manufactures representative should be onsite during the quality assurance/ quality control evaluations of the mock –up to ensure that no deviations from the warrantable assembly are made.

(5) Testing

(a) All testing requirements should be carefully reviewed for proper time in which testing is to be performed and who the testing will be performed by.

(b) Testing of mock-up if required by contract should be performed before the permanent work is in place. These requirements should be fully reviewed and performed in accordance with the prescribed requirements.

(c) The QAR should be aware of any manufacturer specific testing that must be performed and any coordination that may be needed for roofing system manufacturer’s representatives or installation personnel to be present for such testing.

(6) Discrepancies or Changes

(a) Should the QAR discover or be made aware of a change or discrepancy with a roofing system, assembly, component or the general installation of the roofing feature, this change should be carefully evaluated before work proceeds. Any changes that alter the design of the cladding assembly must be evaluated with the COR, ACO or CO and the DOR to ensure contract compliance.

(b) In order to maintain roofing warranty, the installer and the roofing system manufacturer need to be included in the resolution of any issues discovered.

(7) The QAR should review sequencing of trades for all systems and components interfacing with the roof covering. Temporary protection measures must be in place to eliminate moisture intrusion into the roof assembly prior to installation of all materials.

b. Initial Phase

(1) Materials Inspection

(a) All materials must be inspected for compliance to the specification, submittals and the overall compliance to the manufactures warrantable system.

(b) All Non-complaint materials should be removed from the site to prevent any accidental incorporation in the permanent work.

(2) Inspection of Work

(a) The QAR should note primary inspection points and any site specific conditions

(b) Level of Workmanship

(c) Fasteners and Thermal Bridges: See section on thermal bridges. The QAR should ensure that there are no unintentional or unnecessary thermal bridges caused by fasteners or other connections. The QAR should pay special attention to fastener requirements, especially requirements for gaskets or seals.

(d) Lapped joints

The QAR should pay special attention to the contract compliance of lapped joints, since these are critical to shed water.

(e) Sealant locations

The QAR should be aware of any locations where the sealant is critical to keep moisture out of the building, and ensure that the sealant is continuous.

(f) Terminations and transitions

All terminations and transitions should be carefully inspected for any issues prior to work continuing.

(g) Storage

The QAR should ensure that materials are stored per manufacturer’s instructions and contract requirements to reduce warping, thermal expansion and contraction, moisture exposure, and condensation build-up between sheets.

(3) Special Considerations by installation

(a) Steep Slope: Roof coverings are most susceptible to moisture intrusion at joints. The QAR should inspect for minimum lengths of end laps and continuous sealant or tape as per the details.

(b) Low Slope: Roof coverings are most susceptible to moisture intrusion from ponding water. The QAR should pay special attention to roof drainage slopes and crickets to prevent pockets where water can pond. The QAR should inspect for continuity at all seams. Since the covering is the water resistant layer, the QAR should ensure that the substrate is free of chemicals or sharp edges that could damage the covering.

c. Follow-up phase

(1) The QAR should verify that work is proceeding in a consistent manner, paying close attention to critical inspection points:

(a) Skylights, penetrations, and roof curbs

The QAR should be familiar with installation and flashing details.

Where possible, the QAR should ensure coordination of roof penetrations to not penetrate through roof covering seams and joints. This will reduce possible water intrusion points.

(b) Terminations and transitions

(c) Lap and Joint conditions

(d) Fasteners and thermal bridges

(e) Sealant locations

(f) Drip Edges

(g) Flashing

(2) The QAR should monitor installation temperatures: recommended installation temperature range, special requirements for excessive temperature installation, and actual temperature during installation. Deviations in temperature can result in improper joints due to thermal movement.

(3) The QAR should document the installation process:

(a) Inspection Reports: Daily QA reports and manufacturer’s required field inspections.

The QAR should be aware of the contract requirements for intermediate manufacturer’s field inspections during the work.

(b) Daily photos of installation

(4) The QAR should control access onto completed parts of the roof to protect during construction.

(5) If required by contract, finished applications of roofing are subject to inspection and leakage test. The QAR should ensure that this is conducted properly after completion of roof covering installation.

(6) The QAR should take the proper measures to execute and document Damage repair and Leak Repair

d. Constructions Installation Means/Methods

(1) Means and methods vary depending on the roofing system type and building type.

Common means and methods for roofing system construction include providing safe access, fall protection, material handling and placement on the roof and environmental conditions.

(2) All required safety provisions prescribed by the EM 385 1-1 as applicable to the roofing work should be outlined in the AHA, Roofing plan and discussed in the Preparatory meeting.

(3) All structural work must be complete and fully inspected prior to roofing activities commencing.

(4) In the installation of built up asphalt or wet mop asphalt roofing applications, all required safety measure must be taken for heating and placing hot asphalt materials.

(5) The QAR should ensure that the contractor is taking all needed measures to ensure that environmental conditions and material specific application conditions are met during the construction of the roofing system.

e. Inspection Points

(1) Material compatibility- The QAR should check the compatibility of fasteners and anchors to main material and substrate, and ensure separation of incompatible components. This applies to flashing, trim, closure strips, accessories, gutters, roof curbs, etc.

(2) All material must be stored to prevent environmental damage to the material including low temperature damage to adhesives, solvents and bituminous roofing material.

(3) Insulation materials can be susceptible to moisture and should be kept in a dry location.

(4) During installation roofing materials staged or stored on the roof must be secured to prevent wind from blowing materials off of the roof.

(5) Steep Slope-

(a) If self adhered membrane or bituminous felt paper material is used as the water proofing layer(s) in the roofing system, all joints should be staggered and lapped to shed water down and out of the system.

(b) Seams on a standing seam metal roof system should be neatly bent into their final configuration. Poor bending, damage from bending or incomplete bends constitute a deficiency in the work.

(c) Standing seams and joints in metal sheet materials must be sealed to ensure water tightness.

(d) Shingles of the various types should be free from damage and installed according to the manufacturers written instructions.

(e) All penetrations should be sealed both at the control layer and on the surface layer to prevent water intrusion.

(f) Flashings must be interfaced with the control layer and should be lapped to positively shed water.

(6) Low Slope

(a) Membrane roofing materials must be stored in such a fashion to prevent permanent distortion or damage to the material.

(b) Adjacent or overhead work such a welding, brazing or cutting can damage roofing membranes. The QAR should inspect carefully for any holes made by these activities.

(c) Loose fasteners on the membrane when stepped on or dropped can puncture the membrane. The QAR must assure that housekeeping is being performed during roofing installation.

(d) Adhesives and waterproofing layer materials must be applied and properly allowed to set up in accordance to the manufactures written instructions.

(e) Membrane roofing system seams must be carefully inspected and fully bonded.

(f) Bubbles or wrinkles in the membrane must be rolled out or if the case of a wrinkle cut and patched back.

f. Special Inspections and Testing

(1) The QAR should ensure that the manufacturer’s field representative is present during the initial work as required by the contract.

(2) The QAR should ensure that all field tests and reports are done as required in the contract and by the manufacturer, and are conducted by a qualified representative. Note if any field tests are required from independent testing agencies.

(3) Roof systems often require as a condition of the warranty that the manufacturer of roofing systems, specifically for low slope membrane roofing systems, that a complete inspection and documentation of the roof system be performed. The QAR should be present for this inspection to document and assure corrective action is taken a properly completed. Release of the warranty for many roofing systems is contingent upon satisfaction by the manufacture of the system.

(4) Flood testing of the roof system is often specified to demonstrate the water tightness and proper drainage of the roof system. The QAR should be present for such tests and should fully document the results including any deficiencies found. This testing may or may not be specified to be performed by an independent entity and may be performed by the contractor or installer. The installer should always be present for such tests.

g. Documentation

(1) The QAR needs to verify that all manufacturer inspection and warranty inspection reports performed on roofing systems have been submitted.

(a) Material Test Reports: The QAR should check that they have been submitted and approved

(b) Performance testing: The QAR should check for air infiltration tests, water leakage tests, load tests, uplift tests.

(c) Warranty: The QAR should ensure that all work is done satisfactory to warranty the work and that all warranty related information is submitted to the Government.

(2) The QAR should document any field inspection activities performed to include testing, daily inspection, or the three phase inspection process performed for this feature in the daily report for the project.

(3) The QAR should collect any manufacturer site visits or inspection notes during the construction process from the QCM and document these in the contract file.

(4) The QAR should take photos of the work periodically and photographically document any deficiencies found during the inspection process.

(5) The QAR should collect or have submitted all roofing system related inspection or test reports from the QCM and document them in the contract file.

CHAPTER 4

Fenestrations

4-1. Definitions.

a. Fenestrations- The arrangement, proportioning, and design of windows and doors in a building envelope.

b. Curtain wall- An exterior non-load bearing wall. Such walls are often anchored to columns spandrel beams or to structural walls or floors.

c. U-factor- a measure of the flow of heat through an insulating or building material: the lower the U-value, the better the insulating ability.

d. Solar Heat Gain- refers to the increase in temperature in a space, object or structure that results from solar radiation. The amount of solar gain increases with the strength of the sun, and with the ability of any intervening material to transmit or resist the radiation.

e. Visible Transmittance- the percentage of visible light that passes through a window or material.

Figure 2: (Left) is an example of a large curtain wall assembly commonly seen in construction applications. (Right) a small fixed aluminum frame window.

4-2. Materials.

a. The QAR may encounter a variety of fenestration assemblies of different configuration, components and materials. Several of the common materials that may constitute fenestration assemblies and components are:

(1) Aluminum

(2) Steel

(3) PVC

(4) Wood

(5) Fiberglass

(6) Glass

(7) Sealants

(8) Rubber, Nylon, EPDM, Butyl

4-3. Applications.

a. All buildings constructed in the built environment contain fenestrations. It is important for the QAR to understand impacts and interfaces fenestrations have in a high performance building envelope. Because fenestrations have a significant impact on the energy consumption of buildings, application of high performance fenestration assemblies are often designed and modeled with specific properties and expected performance intention. This is particularly important with regard to reduction of thermal bridging. Deviation from the design during construction phase will have a significant impact on the performance of the assembly and the QAR should ensure that the contractor is installing or constructing fenestrations properly in accordance to the contract documents.

b. High performance fenestrations will interface with the other components of the building envelope assembly depending on the wall type. The two critical interface points in the assembly are with the thermal layer and the air/vapor /water control layer. During construction, the continuity of both the thermal plane and the air/vapor/water control layer(s) plane with the fenestration assemblies must be maintained.

c. The QAR should be aware that weather stripping, gasketing, seals and thresholds are components of fenestrations that directly impact the air leakage and water penetration through these assemblies. These assemblies are considered part of the air barrier plane and need to be sealed. Due to the nature of doors; seals, gaskets and thresholds should be present but leakage will still occur in door assemblies including single, double, sliding, bi-fold, large bay doors of folding, overhead or coiling type.

d. The QAR should be familiar with the common types of fenestrations such as:

(1) Curtain wall

(2) Store Front Assemblies

(3) Sky lights

(4) Fiberglass Panels

(5) Fixed or Operable Windows

(6) Doors (coiling, bi-fold, overhead, folding, single, double or sliding)

4-4. QA activities.

a. Contract Document Review

(1) Thermal Layer Continuity

(a) It is important for the QAR to be aware that the placement of the window in the wall affects the thermal value of the assembly. The QAR should be looking to ensure that for windows, the glazing unit of a fixed window assembly is in the same plane as the exterior insulation. Windows that are part of a concrete wall system that has an insulation layer between the two layers of concrete should be placed in that insulation plane.

(2) Interface with the air, vapor and water control layer(s)

(a) The QAR should be aware that the control layer(s) will need to interface with the fenestration assembly and maintain…