UK5 KraftFelt Separating Sheet
In order to maintain the correct application viscosity for ambient applied cutback asphalts, the applicator shall employ equipment to maintain the cutback asphalt at a minimum of 110° F when measured at the point of application.
Required Guidelines for Heating Asphalts
2. Heating equipment temperatures shall be maintained at less than 25° F below the flash point for hot applied asphalts.
3. Asphalt shall not be kept at high temperatures for prolonged periods.
4. Asphalt shall not remain in open rooftop containers for long periods of time.
5. Pipelines shall be insulated to aid in maintaining the correct asphalt temperature on the roof.
6. Asphalt shall be circulated while it is heating.
In order to maintain the correct application viscosity for hot asphalts, the applicator shall follow the correct EVT (Equiviscous Temperature) guidelines. EVT is the temperature at which hot applied asphalt has the correct viscosity for installation of the roof system. The EVT range is 25° F above or below the EVT, thus giving a maximum range of 50° F. The EVT application temperature range is measured in the asphalt mopping cart or machine spreader at the time of application. The EVT for hot asphalt is as follows: For cart applications 125 centipoise; and for machine applications, 75 centipoise.
Temperature affects the viscosity and flow characteristics
of asphalt, and therefore, the weight or application quantities. Temperatures
that are too high can result in asphalt that has low viscosity and greater
flow characteristics when applied, and thus can cause:
2. Incomplete asphalt coverage
3. Asphalt voids between reinforcing sheets
4. Diminished asphalt waterproofing qualities.
5. Reduced asphalt weathering durability
6. Project site safety hazards
Temperatures that are too low can result in asphalt
that has high viscosity and lower flow characteristics when applied, and
2. Poor adhesion
3. Inadequate lamination of sheets
4. Slippage of the reinforcing sheets
5. High expansion properties
6. Low asphalt tensile strength
Base Sheet Installation
Nailing pattern for mechanically fastened base
Installation of Base Sheets
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