The first step in successfully installing a thermoplastic membrane roofing system is to properly plan and coordinate the job. This means that you will require the proper tools and correctly estimate the quantity of materials needed. Along with the tools you would need for any roofing job, you may also need the following:
Good scissors- Square
- Seam roller
- Brushes and rollers
Welder (hand, automatic and/or electromagnetic) depending on the type of attachment method and membrane detailing being used
Estimating material
In order to correctly estimate the membrane material that will be required, you will have to calculate the following:
- The area of the roof (length x width).
- The perimeter of roof.
- The length, width and height of all parapets.
- The length and height of all walls that require flashing.
- The length, width and height of all curbs.
- The dimensions of all roof penetrations including drains, vent pipes, anchors, chimneys etc.
These dimensions will allow you to estimate the following materials:
- Number of membrane rolls.
- There are various types of rolls, each manufactured for specific purposes. Always use the correct product for the given application.
- Roll sizes vary depending on the size of the job and vary by manufacturer and product. A standard roll size is 2 m x 20 m (6.5 ft x 65 ft). Although other sizes may be available. Allow for 100 mm (4 in) minimum overlap between sheets and for stripping.
- Length of bars (battens) or number of disks (depending on type of attachment).
- Quantity of adhesive (depending on type of attachment).
- Length and dimensions of metal flashing (PVC or TPO coated for bonded flashings).
- Tonnage of gravel ballast (if required).
- Number of rolls of protection mat (if required).
- Length and number of screws, plates and compression bars, and rod.
- Quantity of sealant.