Standards & Specifications

Flowtite® Standards & Specifications

Thompson Pipe Group is the North American manufacturer of Flowtite®. The family-owned company produces Flowtite® FRP in a broad range of diameters, stiffness grades, and pressure classes. The flexibility of the filament winding process allows pipe to be produced in any length from 10 to 40 feet, as required by a given installation.


ASTM and AWWA standards apply to a variety of fiberglass pipe applications, including sanitary sewage, water, and industrial waste. These performance-based product standards require testing in each case, and may include stringent qualification and quality control tests. Flowtite® pipe is designed to meet all the standards listed below.

Guide specifications for engineers designing projects with fiberglass pipe in various applications are also included.


ASTM D3262 Fiberglass Gravity Sewer Pipe guide spec
ASTM D3517 Fiberglass Pressure Water Pipe guide spec
ASTM D3754 Fiberglass Pressure Sewer Pipe guide spec


AWWA C950 Fiberglass Potable Water Pipe guide spec
AWWA M-45 Fiberglass Pipe Design Manual


ISO 10467 Plastic piping system for pressure or non-pressure sewerage
ISO 10639 Plastic piping system for pressure or non-pressure water supply


DIN 16868 Glass fiber-reinforced polyester resin pipes
BS 5480 Pipes and fittings for water and sewerage


Flowtite® is cost-effective, with low initial installation costs, long effective service life, and low operating costs for your sewer, hydroelectric, or industrial project. It offers an extremely smooth bore with a list of other features, all of which add up to provide you with the optimum installed and life-cycle cost system.

  • Hazen-Williams flow coefficient of C=150
  • Low friction means less pumping energy needed and lower operating costs
  • Manning’s “n” flow coefficient of 0.009
  • Minimal slime buildup means lower cleaning costs
  • Excellent abrasion resistance

Other Flowtite® properties, which are useful when designing a project with fiberglass pipe include:

  • Colebrook-White coefficient may be taken as 9.5 x 10-5 ft
  • Polsson’s ratio ranges from 0.22 to 0.29
  • Thermal coefficient of axial expansion and contraction for Flowtite® pipe is 13 to 17 x 10-6in/in/oF