شینگل سقف شیبدار
As with submittal approval, be cautious in approving materials, systems and details that are not in accordance with the contract documents while performing field observations (Figure 16). For example, the roofing crew may desire to use different fasteners to attach the membrane because the approved fasteners were not sent to the job site. Before accepting the fasteners, determine if wind uplift test ratings will be affected and if the membrane manufacturer will approve the alternative fasteners. Another example is a penetration detail that the foreman desires to flash differently than detailed. Is the change proposed in order to provide a better detail, or is it being proposed because it is simpler and cheaper to install? If the proposed detail is not as conservative as the original detail, it should probably not be approved. Requests to use alternate details of materials should be referred to the Designer of Record for written approval.
- Write daily reports and give them expeditiously to the contractor (and to the roofing designer if the observer is not an employee of the structural firm that designed the roof). Report copies should be included in the file prepared for the Owner, as discussed in section 4.4.5.
NON-DESTRUCTIVE EVALUATION (NDE)
After completion of all building construction, but before occupancy, consideration should be given to NDE of the roof to check for excessive moisture within the roof system. The purpose of the NDE is to find areas of wet insulation caused by moisture entrapment during application or leakage caused by roof system defects. Low voltage electronic leak detection may be employed continuously to monitor roofs to warn of leaks before they migrate to the building interior. This technique is usually employed on high-risk occupancies, such as hospital operating rooms, computer facilities, museums, etc. See the Integrity Testing for Roofing and Waterproofing Membranes Resource Page for further information.
At the pre-roofing conference the contractor should be notified if NDE is to be conducted. (Notification may result in greater diligence in application and care of the completed roof).
At the end of the project, the owner should be provided a file with the following items:
- Contract drawings and specifications related to the roof
- Approved submittals
- Minutes from the pre-roofing conferences
- Field observation reports
- Pertinent construction correspondence related to the roof
- Warranty (if specified)