In the commercial roofing field, there is a great interest in green roofs, LEED, reflectivity, emissivity, photovoltaics, carbon footprints, sustainability, recyclables, and landfill capacity. With petroleum reaching $100 per barrel, energy conservation and efficient building design are certainly in the forefront of our minds; however, in the flood of articles being published, there is very little on what the individual property owner or building manager can do (short of starting over with a new building design or adding thermal insulation at the time of reroofing or recover).
Inspecting and Maintaining What We Have
Many previous issues of Roofing News have focused on the benefits of inspecting existing roof systems periodically. For buildings that are heated in the winter and cooled in the summer, the in-situ thermal resistance of the roof insulation is a huge energy saver – not the designed R-value, but the in-place insulation value. This can differ considerably from what the intended R- or U-value was due to air leakage, wet insulation from either condensation or roof leaks, or poor installation practices.
Infrared surveys have proven worthwhile in detecting air leakage and wet insulation, but are not effective with ballasted roofs, vegetated roofs, protected roof membranes, and some instances of cellular thermal insulation. When wet thermal insulation is detected, it can be very cost effective to do partial roof replacement, returning the roof system to its designed thermal performance as well as its intended life. Nuclear and capacitance devices can also be used by an experienced equipment operator, but only if the operator is familiar with roofing and verifies the instruments’ readings. The payback on scheduled surveys can be excellent, especially if one considers the shortened life of a leaking roof, the potential loss of decking, wood blocking, and potential business interruption. The same can be said of regularly scheduled visual inspections.
Achieving a Quality Roof System
Even when a roof system has been well designed and has quality materials specified, sometimes the result is less than hoped for. The December 2007 article on ASTM Intl. discussed how ASTM goes about developing a new product specification or recommended practice; however, ASTM sometimes goes further in the roofing and waterproofing area, especially when assisted by RCI Inc. (the Raleigh, NC-based Institute of Roofing, Waterproofing, and Building Envelope Professionals). This is the case with ASTM D7186, Standard Practice for Quality Assurance Observation of Roof Construction and Repair. This document was developed to a great extent by members of RCI Inc., but published through ASTM’s consensus process. Highlights of the joint ASTM/RCI specification follow. (The entire D7186 specification is available for purchase on ASTM’s website.)
Scope. This practice covers procedures for performing visual monitoring of roofing construction in order to:
- Establish guidelines for quality assurance observation practices.
- Define the role and responsibilities of the quality assurance observer.
This practice pertains to daily, full-time quality assurance observation of roofing projects. This standard is applicable to new construction or reroofing projects involving the installation of a new roof system, the removal of existing roofing and installation of a new roof system, or recovering an existing roof. It is also applicable to roofing projects involving repairs or scheduled maintenance to an existing roof.
This practice contains the following information:
- Objectives of the quality assurance process.
- The responsibilities and qualifications of the individual(s) involved in the observations of the roof construction or repair.
- Identification and use of the basic tools or equipment required for the visual roof observation process.
- Monitoring, recording, and reporting procedures.
(This standard does not pertain to quality control processes or techniques performed by persons or entities representing or under contract to the roofing contractor. The quality control process is separate and distinct from the quality assurance observation process.)
Significance and Use.
- Quality assurance observation of roofing projects is an important process for determining if the removal, installation, repair, or maintenance of roofing materials or systems follows the scope and intent of the Contract Documents, and are installed and executed in accordance with accepted roofing practices and the Contract Documents.
- This practice is applied to full-time quality assurance observation of roofing projects involving the removal, construction, and repair and maintenance of low- and steep-slope roof systems and roofing-related accessories.
- This practice establishes the role and responsibilities of those performing quality assurance observation, and includes qualifications of the quality assurance observer, as well as procedures for observation and documentation during the roof construction or repair process.
The Role of the Quality Assurance Observer (QAO)
The presence of, or opinions expressed by, the QAO do not relieve the contractor, manufacturer, or other responsible party of his/her contractual requirements. The information provided by the QAO is for the benefit of the owner (or other client); no warranty of roof performance, expressed or implied, is offered, neither should it be inferred based on the quality assurance observations.
The QAO’s function is to provide onsite observation and reporting of the roof construction process in a clear, accurate, and objective manner, using procedures indicated in this standard. The QAO shall observe and record:
- The general conditions of the jobsite, roof areas under construction, and materials used in the construction process and their storage.
- Pre-existing property damages, or property or material damages that occur during the roof construction process.
- The condition of the substrate and substrate preparation, repair, or replacement procedures.
- The installation and attachment of any base sheets, including the type of fastener or adhesive used, the fastening pattern, and spacing.
- The installation and attachment of any vapor retarders or air barriers, including the type of fastener or adhesive used, the fastening pattern, and spacing.
- The installation and attachment of the insulation layer(s), recover or coverboard materials, including the type of fastener or adhesive used, the fastening pattern, and spacing.
- The installation and attachment of the roof covering or repair materials which comprise the finished roof system, including the type of fastener or adhesive used, the fastening pattern and spacing, as well as specific material quantities, temperatures, and measurements appropriate to the type of roof system under construction.
- The installation and detailing of the roof system flashings at perimeter and roof penetration locations.
- The installation and detailing of the sheet metal roofing accessories such as, but not limited to counterflashings, coping caps, joint covers, and edge and fascia metals.
- The installation of roof surfacings or coatings.
- The installation of temporary weather seals at the end of the workday or prior to inclement weather.
- The installation of any other roof components specified in the project specifications.
- The weather conditions that occur during the roof assembly installation.
- The crew size and foreman, and type of work being performed on a given day.
- All visitors to the site roof and their length of stay.
Qualifications of the Quality Assurance Observer.
Significance of qualifications:
- It is necessary that the person(s) performing quality observation of the construction process understand the project specifications and the specified roof system. Knowledge of industry-accepted good roofing practices is critical to the success of the quality assurance observation process.
- A record of experience and training shall be maintained by the QAO and submitted to the project file. (A Record of Training & Experience sample form is available for optional use in ASTM D7186.)
- A thorough understanding of the contract documents, specifically the project specifications, construction detail drawings, pre-bid and pre-construction conference minutes, and any addenda to the roofing specifications is required.
- A thorough understanding of the type of roof system specified, including general knowledge of the manufacturer’s requirements, is required.
Technical qualifications of the QAO can be achieved by:
- Completion of specialized training or certification in Quality Assurance Observation. The training or certification program shall be specific to roofing quality assurance observation and shall be administered by an industry-recognized organization.
- Completion of a roof system application program provided by the roof system manufacturer specified.
Required Project Documents. A copy of the following project documents shall be maintained onsite by the QAO and updated as necessary:
- The contract documents, including scope of work, specifications, roof plan, construction detail drawings, addenda, and modifications.
- The pre-bid and pre-construction conference minutes, and project meeting minutes.
- Stamped material submittals.
- The contractor’s original construction schedule and any revisions.
- Appropriate manufacturer’s literature containing roof system or material application requirements.
- Construction change directives, change orders, and any field orders.
- Written and photographic documentation prepared by the QAO.
- Other pertinent project correspondence.
- An emergency contact list for all pertinent project personnel.
Observation and Recording Procedures. Documentationshall include both a written and photographic record for historical file purposes and shall be made available to all parties involved in the roofing project. Project documentation may begin at the pre-construction conference or earlier and shall be continuous for the duration of the roofing project. Written documentation shall be clear and concise, and present an accurate, objective account of the roof construction project. Reports shall accurately describe the sequence of events, installation methods, workmanship by the contractor, and problems encountered and corrective actions taken.
Pre-construction damage reporting. Thorough examination of building surfaces, equipment, and other property items is necessary to document pre-existing damages prior to commencing construction. (A Pre-Construction Damage Report sample form is available for optional use in ASTM D7186.)
The report shall be distributed to all parties and shall be generated, whenever possible, with the contractor’s representative and building personnel to indicate pre-existing damage. It shall include photographic documentation of the areas viewed and damages noted. The report shall include, but is not limited to, inspection of the roof areas under contract, interior spaces directly below the project areas, condition of related rooftop equipment and adjacent building(s), as well as building façades, pavement, and landscaping in staging areas.
Material delivery and examination reporting. Prior to the start or during the initial staging of the project, and following the delivery of materials thereafter, the QAO shall examine the materials delivered to verify conformance with the Contract Documents. (An optional, sample Material Delivery Examination Report is available in ASTM D7186.)
The report shall note the condition of materials, the manufacturer, specific product designations, approximate quantity, lot or batch numbers, and, if the materials are stored properly, noting the use of pallets, dunnage, tarpaulins, etc., in the report.
The report shall include photographic documentation of the general condition of the material, including any damages or defects in the material.
The QAO shall immediately notify the contractor or its representative if any materials are determined to be damaged or defective.
Daily construction reporting. A report documenting the nature of roofing work performed, progress, problems encountered, and actions taken by given individuals shall be completed each day. An acceptable, recognized reporting format shall be utilized by the reporting QAO. (An optional, sample report form titled Daily Construction Report, Page 1 & 2 is available for use in ASTM D7186.)
The report shall include, but is not limited to, crew size, daily temperatures, wind, relative humidity, weather conditions, roof removal procedures (if applicable), structural deck or substrate condition, deck/substrate preparation, application and securement of any vapor retarders, base sheets, insulation layers, roofing and flashing membranes, sheet metal components, and other related roof accessories.
The report shall record the size of the roof area(s) completed each day, deck repair or replacement dimensions, application temperatures of bitumens or adhesives, fastening pattern and spacing used to secure roof system components, exposure, headlap, side and end lap dimensions of felt or membranes, and approximate linear footage of flashing membrane and sheet metal installation. (Note:The report shall also record any measurements necessary for tracking unit price work items or authorized work in addition to the Contract Work as required by the entity contracting with the QAO.)
The report shall record the use and construction of temporary weather protection (e.g. night seals or tie-offs).
The report shall contain a record of any visitors, including the name and title of the visitor, and nature of the visit to the roof construction site by project managers, building representatives, roof system designer, manufacturer’s representatives, and anyone else.
If workmanship defects are noted, or if the installation of a specific material does not appear to meet the project specifications, the QAO shall notify the contractor, or its representative, immediately.
The report shall note, on the same day, the final resolution of all variances listed in the report. If this is not possible, the QAO shall track these variances daily in the daily construction reports until such time as the final resolution can be documented. It is essential and imperative that the project file be complete and accurate for each variance listed, and that the file contain the resolution and any corrective actions taken.
Photographic documentation of the project shall accompany daily reports.
A roof plan shall be attached to the progress report showing the location of work and date for each day of construction.
The contract documents provide the criteria for compliance of the materials, application, and work procedures for roofing project. The following documents may be useful as supporting literature:
- Roof system installation requirements supplied by the applicable manufacturer, supplier, or distributor of the roof system or material such as ARMA/NRCA/SPRI Repair Manual for Low-Slope Membrane Roof Systems, ARMA/NRCA Quality Control Guidelines for the Application of Built-Up Roofing, ARMA/NRCA Quality Control Guidelines for the Application of Polymer Modified Bitumen Roofing, NRCA/SPRI Quality Control Guidelines for the Application of Thermoset Single-Ply Roof Membranes, NRCA/SPFA Quality Control Guidelines for the Application of Sprayed Polyurethane Foam Roofing.
- NRCA Roofing & Waterproofing Manual, 5th Edition.
Photographic Documentation. A minimum of six photographs shall be taken daily and processed promptly to ensure sufficient photo quality for file purposes, unless modified by mutual agreement.
The photographs shall be separated by date and type of report, and marked accordingly.
The photographic record of the roofing project should accurately and objectively portray the workmanship of the contractor, documenting problems encountered and corrective action, as well as providing normal and acceptable depictions of the installation.
- Documentation and distribution of paperwork shall be performed in a timely manner to prevent delayed communication of pertinent issues to the parties involved.
- Meeting minutes shall be prepared and distributed no more than 5 working days following the date of the meeting.
- Provide copies of all written daily reports to the contractor upon completion of the report, but no later than the commencement of work on the following day.
- At the contractor’s request and expense, provide copies of photographic documentation.
- A specification variance reporting installation, work practices, or material usage thought to be in conflict with the project specifications shall be reported immediately to the contractor, or its representative, to minimize further installation of materials and facilitate immediate corrective action.
Tools and Equipment.
- The QAO shall have and maintain onsite the tools or equipment necessary for performing quality assurance observation of the roofing project.
- The QAO is responsible for maintaining the tools and equipment used by the QAO in good working condition. The repair, maintenance, and calibration of the tools and equipment are the responsibility of the QAO.
- The types of tools and equipment required for the observation of a roofing project are determined, at a minimum, by the nature of the construction and type of roof system.
- The tools and equipment required for quality assurance observation of a roofing project may include, but are not limited to, camera, colored marking tool, tape measure, utility knife, flashlight, thermometer (infrared or direct sensing, or both), wind speed indicator, hygrometer, and seam probe.
- Depending on the nature and logistics of the project, safety equipment, such as personal protection equipment (PPE) or fall protection, may be required for the QAO. If so, it is the responsibility of the QAO to furnish and maintain any and all necessary PPE or fall protection equipment required by the project specifications or regulating authorities. The QAO shall follow all applicable safe work practices.
- The QAO shall provide or have immediate access to a method of communication, located in the roof area, to facilitate immediate communication when conditions arise requiring consultation with project personnel not onsite.
The Benefits of Quality Assurance
RCI has developed (and now offers) educational programs and examinations for Registered Roof Observers. The advantages of having a skilled roof observer involved with the installation process are many: correct, dry, and undamaged materials are installed, the correct thicknesses (R-values) are used, and industry and manufacturer installation standards are followed. Since air leakage is now blamed for most condensation problems and wasted energy, the observer can verify that air barriers are properly tied in to curbs, penetrations, and a building’s wall systems.