Specifications For A Manhole Renewal Project

Resinating Fiberglass Expansion Liners™, their related products and corbels, if needed, earn their 20 year warranty for many reasons specified below.

  • They are manufactured from continuous strands of E-Class fiberglass strands coated with a resin tailored to the environment in which they will operate.
  • The resins used to bond the Resinating Fiberglass Expansion Liners to the walls of a manhole (or to the inside of an existing sewer pipe) are also matched to their projected environment.
  • The Resinating Fiberglass Expansion Liners are custom manufactured to fit in each manhole (and every pipe)…an important plus.

Other factors that enable Resinating to offer a 20 year warranty on its Patent Pending process and products relate to the way Resinating approaches each Project and the specifications it follows.  The critical steps in the Project Process to ensure the quality that Resinating products deliver can be grouped into four areas:

  • Accurate pre-planning of a project.
  • Validation of the plan with the customer prior to fabrication.
  • Quality control in the fabrication process.
  • Structured installation process.


The inspection of the existing manhole is the key first and a major step in ensuring the long term success of a Resinating solution.

Older, existing manholes vary greatly as to their construction methods, materials used and dimensions as well as other factors.  Since Resinating Expansion Liners are custom made for each manhole, all the following information must be defined during the planning stage.

  • Dimensions for the invert, floor and depth of the manhole and the size of the manhole opening.
  • The shape of the manhole – conical, cylindrical, rectangular or other?
  • The location of the manhole – in the street or in an area without traffic?
  • The material used to construct the existing manhole – RCP, brick, poured concrete or PVC?
  • The manhole type – waste water, storm water, industrial or steam, noting any special conditions such as chemical exposure or high temperature ranges.

All of the above factors need to be understood to properly design and specify the correct resins, polymers and methods to be used in the construction and installation of a Resinating Liner.

Validation of the Plan

After securing all of the pre-planning information, Resinating will provide detailed CAD drawings with written specifications for the project including certification that the manholes will be fabricated in accordance with ASTM D 3753-05, latest edition, specifications for the customer’s approval.  While Resinating liners for manholes are for the most part pre-designed and engineered, Design Calculations and a Registered Engineer`s stamp are available, if required by the customer.


Resinating Fiberglass Expansion Liners are manufactured using continuous E-Class fiberglass strands and a premium grade resin suitable for the specific project.   A premium-grade, white, UV-resistant pigment is used throughout the laminate. ABSOLUTELY NO FILLERS are used in the construction of Resinating’s liners and corbels to ensure a structurally consistent and strengthened laminate.  The approved polymeric bonding material will be supplied by Resinating for the project application.

The laminate shall MEET or EXCEED all structural requirements of ANSI/ASTM D 3753-05, latest edition, Standard Specification for Glass-Fiber-Reinforced liners.

The flexural strength in the Axial direction for ASTM D790 shall MEET or EXCEED 20,000 psi.

Since the liners are constructed as a SOLID FIBERGLASS LAMINATE, the need for reinforcement ribs is eliminated.  The fabrication method may vary based on the needs of a specific project requirements but will be consistent with the specifications on the specification drawings.

The Resinating Fiberglass Expansion Liners will be stiff enough to resist expected vertical and horizontal external loads when properly installed.  Pipe stiffness factors for the shell shall be in accordance with ANSI/ASTM Standard Specification for Glass-Fiber-Reinforced Liners as specified on the approval documents for the project and be consistent with an AASHTO H-20 load rating, when required, as noted on the specification drawings.  Third party test results are available upon request.

Standard dimensions for Resinating Fiberglass Expansion Liners used in manholes are:

  • Diameter: 3’ to 15.5’
  • Depth: 2’ to 40’

However, since all Resinating Fiberglass Expansion Liners are custom manufactured, they can be fabricated in virtually any size to meet the needs of the customer.

The liners will be built in one piece in the shape required for the project unless otherwise specified in the approval documents and cut for compression and insertion into the manhole in the field. The top cone section and closed bottom will be bonded to the liner in the field

Each manhole liner will be properly marked and labeled in accordance with the ASTM standard used in the production of the liner. The label shall contain the following information:

  • The ASTM method used, if applicable.
  • The Resinating LLC Approval Number.
  • The Resinating LLC Serial Number.


Installation of a Resinating Fiberglass Expansion Liner in a manhole is performed by Resinating LLC itself or an Authorized Resinating Installer.

During the installation process it is important to use suitable means to lift and set the Resinating Fiberglass Expansion Liners into place in the manholes such that the liners are not subjected to impact loads due to being dropped or being rolled over rocky terrain.

Generally speaking, installation steps include:

  • Addressing all requirements related to safety, working in a confined space, dealing with traffic control, the positioning of barricades and protective equipment for personnel…Safety First.
  • Pressure washing the manhole.
  • Double checking all measurements, making adjustments as needed.
  • Cutting the liner and other fiberglass parts per plans.
  • Applying a primer to the floor and walls to facilitate adhesion in spite of dampness.
  • Applying the bonding agent to the floor.
  • Installing the floor sections
  • Compressing the cut liner to fit in the manhole.
  • Applying the bonding agent to the walls.
  • Inserting and installing the manhole liner.
  • Applying the bonding agent to the corbel, if one is required.
  • Installing the corbel section.
  • Fiberglassing all seams and joints
  • Cutting ports and injecting bonding material if needed to fill voids.
  • Fiberglassing over the injection ports.
  • Marking and tagging the manhole liner with required information as  indicated above.

There is a slide set documenting the installation of a manhole liner at our website, www.resinatingllc.com under the 1-Day Install tab.

The Bottom Line

Resinating LLC works within exacting specifications and processes for creating and installing Resinating Fiberglass Expansion Liners in manholes.  As a result, Resinating is proudly able to offer its customers a 20-year warranty while generating significant savings for them as they repair and renew their manholes.