Roof Assembly Contents:
Preinstallation Conference & Project
The roofing assembly plans, specifications, building codes, and contract documents shall be reviewed during the preinstallation conference. Any discrepancies between the foregoing and Fields' requirements shall be resolved for guaranteed systems.
The following are required during
the preinstallation conference:
2. Establishment of construction trade schedules and practices including installation of a temporary roof and walkways so as to prevent damage to the roof system membrane.
3. Construction of walls, curbs, drains, and other deck penetrations prior to start of installation of the roof system.
4. Designation of access, staging, and storage areas on the project site.
5. The definition of acceptable weather conditions and working temperatures. For guaranteed systems, Fields must agree in writing to less stringent weather conditions than those stipulated in the Waterproof Membrane Construction section.
6. Provision for on site monitoring after the roof system has been installed so as to ensure that other trades do not damage the roof system.
7. Clarification of related EPA and OSHA regulations, including the safety of other personnel on the project site.
If changes in these conditions are desired, the
party requesting the change shall:
2. Obtain written agreement of the desired changes from the designer and for guaranteed systems from Fields.
General Waterproof Membrane Construction
2. Slope shall be provided for positive drainage of the roof assembly. The criteria for determining positive drainage is that there shall be no standing water on the roof assembly 48 hours after a rain following dry weather conditions. A positive drainage design also includes the correct number, size and placement of roof drains, scuppers, and gutters as well as crickets and saddles with sufficiently sloped valleys.
3. During the installation of roof system components, entrapment of moisture shall be prevented. Moisture in or on components can cause the roof system membrane to blister. If precipitation occurs prior to the completion of the roof system membrane, the installation area shall be dried or allowed to dry before continuing the project.
4. On roofs where the slope is greater than 1.75" per horizontal foot, the roof system reinforcing sheets shall be installed parallel to the slope. This method of installation is termed as "strapping the" sheets and may be employed on lower slopes as well.
5. Roof system reinforcing sheets shall be installed continuously. Irregularities, such as ridges, blisters, or raised seams, shall be cut and repaired prior to installation of additional reinforcing sheets, surface coatings, or the application of reflective surfacings.
6. If conditions do not permit installation of the complete roof system membrane, and the area must be exposed overnight, it is required that the ply sheet laps be sealed either with Fields asphalt coating or M300 RubrMastic prior to departing the project site for the day. All installed reinforcing sheets shall at a minimum be glaze coated with asphalt to temporarily seal the surface at the end of each day's installation. A wide blade squeegee shall be used to apply the glaze coat to help achieve a thin film of 15 pounds of hot applied asphalt or 2 gallons of ambient applied asphalt per 100 square feet.
7. Roof traffic shall be prohibited over recently installed reinforcing sheets so as to prevent the displacement of soft asphalt termed voids, until the asphalt has set-up firm enough for light traffic.
8. The substrate shall be dry, frost free, clean, smooth, and firm. Only the products specified are permitted on the project site. All products, including coatings and mastics, are required to be asbestos free. Each layer of reinforcing sheets, or pre-manufactured membranes shall be started at the same location and installed parallel to all other layers. The flow of water shall be over or parallel to seams, but never against seams. All reinforcing sheets shall be adhered into the specified Fields Asphalt. Each base and ply sheet shall be broomed into the asphalt to ensure a fully adhered, smooth installation. Base sheet side laps shall be a minimum of 2". The quantity of shingled ply sheet layers is the basis for calculating the ply sheet side laps. In no place shall any sheet touch sheet. Reinforcing sheets and pre-manufactured membranes shall extend a minimum of 2" above the top of cants. End laps shall be a minimum of 6" and offset at least 36". The specified Fields Asphalt adhesive, shall be uniformly applied at the following rates per 100 square feet: Ambient applied asphalts 4 gallons, and hot applied asphalts 30 pounds.
9. The 4 types of membrane reinforcing sheets are: base sheets, ply sheets, BasePly sheets, and cap sheets.
Type of Roof Decks that Require
Mechanically Fastened Base Sheets
* Certain gypsum decks may need to have fastener holes predrilled in order for the deck to be considered nailable.
Nails Acceptable for Mechanically Fastening Certain
Roof System Components
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