Metro Cast Specifications for GFRPC

Recommended Specification for Precast Polymer Concrete Panels



A.  Drawings and general provisions of Contract, including General and Supplementary Conditions and Division 1 Specification Sections, apply to this Section.

1.2         SUMMARY

A.  This Section specifies plant-cast, glass-fiber reinforced, polymer concrete panels, including embedded hardware, loose connection hardware, integrated steel stud support framing, and related services for erection and installation.


A.  Section 05120 “Structural Steel” for anchor attachment to steel framing.

B.      Section 07900 “Joint Sealants” for sealing joints between panels.

1.4         SUBMITTALS

A.       General:  Submit the following according to Conditions of Contract Division 1 Specifications Sections.

B.      Samples representative of finished exposed face showing typical range of color and texture and of appropriate thickness.

C.      Shop drawings detailing fabrication and installation of precast polymer concrete panels, including the following:

1. Unit shapes (elevations and sections) and dimensions.

2. Finishes.

3. Joint and connections details

4. Lifting and erection details.

5. Steel support-frame system.

6. Locations and details for hardware attached to structure.

7. Size, location, and details of flex and gravity anchors.

8. Sequence of erection for special conditions.

9. Relationship to adjacent material.

10. Description of loose, cast-in, and field applied hardware.


A. Design Responsibility:  Design precast polymer concrete panels by a registered professional engineer employed or retained by panel manufacturer, licensed to practice in the state of .

B. Manufacturer Qualification:  Firm with a demonstrated capability to produce precast polymer concrete products of quality and scope required for this Project and actively involved in precast polymer concrete production for at least 10 years.  Manufacturer must have sufficient production capacity to produce, transport, and deliver required units without causing delay in the work.  Metro Cast Corporation, 6170 Commerce Dr., Westland, Michigan 48185, phone 734-728-0210 is used standard for work under this section.

C.  Erector Qualifications:  Regularly engaged for at least 5 years in erecting precast polymer concrete panels similar to those required in this project.

D. Welder Qualifications: Qualified within the past year according to the American Welding Society codes and specifications.

E. Field-Erected Mockup: Prior to installation of precast polymer concrete units, erect mockups for each configuration and finish required.  Fabricate additional mockups until color, texture, and pattern is acceptable to Architect.


A. Delivery and Handling:  Handle and transport units to avoid stress or damage.

1. Lift or support units only at points indicated on the shop drawings.

2. Place non staining resilient spacers of even thickness between units.

3. Support units during shipment on non staining chock-absorbing material.

4. Protect units from dirt and damage during handling and transport.

B. Jobsite Storage:  Store units to protect from contact with soil, staining, and physical damage.

1. Store units with non-staining resilient supports at the same position as when transported.

2. Store units on firm, level, and smooth surfaces.

3. Place stored units so that identification marks are readily accessible.


A. Panel systems shall be guaranteed against defects in materials and workmanship for a period of five (5) years from the date of completion.

1. Defective panels shall be repaired or replaced as required.



A.      Steel shapes, Plates, Bars: ASTM A36.

B.      Shop Primer:  For exposed carbon steel anchors, SSPC-Paint 13.

C.      Galvanized Finish: For exposed carbon steel anchors, ASTM A 153, hot dipped after fabrication.

D.     Steel Stud Framing System: Fabricate of material size, shape, weights, and details as indicated on shop drawings.

1.      Galvanized stud and tracks, formed from steel conforming to ASTM A 446, Grade D.

a)      Provide studs with minimum yield strength of 50 ksi.

2.      Finish, hot dip galvanized, ASTM A 525 with minimum G-60 coating.

E.      Touch up galvanized surfaces damaged by welding procedures according to ASTM A 780.


A.      General: Combine thermosetting resin, graded silica sand, and stable non fading paste pigments premixed in proper proportions and reinforced with woven fiberglass cloth to produce panels that comply with the following:

1.      Compressive Strength (ASTM D695) 10,000-12,000 psi.

2.      Tensile Strength (ASTM D638) 1,000 – 2,000 psi.

3.      Water absorption less than 0.1%

4.      Coefficient of Expansion – 0.0000125 inch/deg.F.

5.      Thickness – ¾ inch minimum.

6.      Combustibility (ASTM E36) Noncombustible.

7.      Flammability (ASTM E84) – Class A.

2.3        FABRICATION

A.         Forms:  Construct of rigid materials that will result in finished product conforming to profiles, dimensions, and tolerance indicated.

B.         Steel Stud Framing System: Prefabricate welded steel stud frame assemblies according to shop erection drawings.  Touch up accessible welds after fabrication.

C.         Proportion and Mixing: Carefully measure amount of mix constituents to achieve desired mix proportions.

D.         Form intricate details, incorporate formers or infill materials before materials reaches initial set to ensure complete bonding.

E.         Insert and Embedments: Properly embed inserts

F.         Dimensional Tolerances: Manufacture units so that each panel complies with  the following dimensional tolerances

1.      Overall height and width of finished units, measured to face adjacent to form.

a)      10 feet or under, plus or minus 1/8 inch.

b)      Over 10 feet, plus or minus 1/8 inch per 10 feet.

2.      Angular Deviation of Plane of Side Mold: 1/32 inch per 3 inches of depth or 1/16 inch total, whichever is greater.

3.      Variation from Square of Designated Skew (difference in length of two diagonal measurements): 1/8 inch per 6 feet or ¼ inch total, whichever is greater.

G.         Position Tolerances: Measured from datum line location, as indicated.

1.      Steel Studs or Track: Plus or minus ¼ inch.

H.         Finishes: Exposed panel faces to match existing precast and cast-in-place concrete. Joint marks, grain, or other obvious defects on panel faces are not acceptable.

I.          Curing: Employ curing method that will ensure sufficient strength for removing units from form.

J.          Panel Identification:  Mark each precast polymer concrete panel to correspond with identification mark on shop drawings. Mark each panel with its casting date.


3.1         INSPECTION

A.      Erector Responsibility: Prior to installing units, check jobsite dimensions affecting erection of precast polymer concrete units.  Bring to the engineering department’s attention any discrepancy between design dimensions and field dimensions that could adversely affect installation.  If discrepancies do exist, do not proceed until corrected or until installation requirements are modified as acceptable to Architect.

3.2         ERECTION

A.      Lifting and Setting:  Lift precast polymer concrete units at lifting points established by manufacturer.  Set precast polymer concrete units level, plumb, and square within allowable tolerances.

B.      Support and Bracing: Provide temporary supports and bracing, as required to maintain position, stability, and alignment while units are being permanently connected.

C.      Fastening:  Fasten precast polymer concrete units in place by bolting or welding, as indicated on shop drawings.

1.      Have qualified welder perform field welding.

D.     Panels shall be installed plumb and true, free of any warping or twisting, using procedures recommended by panel manufacturer.

3.3         PATCHING

A.      General:  Patching will be permitted provided structural adequacy of unit and appearance are not impaired, when accepted by Architect.

B.      Patching Mix:  Match color and texture of precast polymer concrete unit.  Blend and mix materials so that cured patching matches adjacent surfaces.

3.4         CLEANING

A.      General:  Perform cleaning procedures as recommended by precast polymer concrete unit manufacturer.

1.      Clean soiled precast polymer surfaces with detergent and water, using soft fiber brushes and sponges, and rinse with clean water.

2.      Prevent damage to precast polymer concrete surfaces and to adjacent materials.