ISO 9001 Certified · FRP/GRP Grating Manufacturer · Since 2004 · Exporting to 45+ Countries

Installation Guide

Full engineering installation specification per ZeAllgrate Guidelines for the Engineer & Designer — loads, spans, clips, cutting, guardrail, ladder and stairs.

Design Criteria

Pedestrian Walkway Minimum Design

Minimum design loads and deflection for molded FRP grating walkways. [ZeAllgrate p.3, §7.1]

ParameterValue
Uniform live load50–65 lb/ft² (psf)
Concentrated load250 lb
Dead load (grating self-weight)3.75 lb/ft² (psf)
Maximum deflectionSpan L/120 OR 3/8" (9.5 mm) — whichever is the smaller value
Spans

Recommended Molded Grating Spans

Support spacing and the maximum clear span each panel depth will carry for pedestrian service. [ZeAllgrate p.3, §7.2]

Grating DepthAcceptable Clear Span
1" deepUp to 3′-0" (914 mm)
1-1/2" deep3′-0" to 3′-6" (914–1067 mm)
2" deep4′-0" to 4′-6" (1219–1372 mm)

Keep support beams at 36" or 48" on center. Always confirm the exact panel against the certified load/span chart for your deflection criterion.

Cantilever

Cantilever (Overhang) Limits

Maximum projection beyond the last support centerline. [ZeAllgrate p.3, §7.3]

Grating DepthMax Overhang from Last Support CL
1" deep6" (152 mm)
1-1/2" deep / 2" deep12" (305 mm)

Hold-Down Requirement

Each cantilevered panel must be held down to at least 2 supports.

Clip Count

Use at least 3 hold-down clips per interior support to restrain the overhanging section.

Never Free-Overhang

An unrestricted cantilever beyond these limits violates ZeAllgrate guidance.

Fastening

Hold-Down Clip Schedule

Molded grating clip and splicing hardware. [ZeAllgrate p.3–4, §7.4/§7.5; FGRAT p.16]

ItemSpecification
M hold-down clipsMinimum 2 per support beam; max spacing 4′-0" (1219 mm) o.c. per beam
Clips per panelMinimum 4 hold-down clips per grating panel
F end-abutment (splice) clipsMaximum 24" (610 mm) o.c. where panel edges abut without a support
Unsupported cut holesUp to 1/3 of panel width without added support
Edge bandingNot required structurally — FRP cannot be welded; applied only to prevent stub-bar injury
Pultruded

Pultruded Grating Fastening (MI-60 / FC Clips)

Mechanical fastening of pultruded ZeAll Pultruded grating. [ZeAllgrate p.4, §7.5; drawings G & H]

ClipDrill / Fastener
MI-60 clipField-drill 5/16" hole; fix with 1/4" × 2-1/4" bolt
FC clipMounting hole 9/32" (0.281"); fix with 1/4"-20 × 1-1/2" truss-head bolt
General rule≥2 clips at max 4′-0" (1219 mm) o.c. per support beam; minimum 4 clips per panel
Fabrication

Cutting Tools & Edge Sealing

Field cutting and sealing of cut edges. [FGRAT p.15–17, §7.7/§7.8; DURA p.4]

Cutting Tools

Carbide-tipped saw blade, abrasive cutter, or masonry blade. Wood-working tools may be used with abrasive blades.

PPE / Safety

Wear dust mask, eye protection and gloves — FRP dust is abrasive. Wet cutting reduces airborne dust.

Seal All Cut Edges

Spray-can epoxy clear coat ≈ 100 lin.ft / can; half-pint kit covers 20–40 lin.ft. Seal every cut edge and hole.

On concrete: masonry bit + concrete anchor bolts. On steel/wood/FRP: drill + truss-head bolt. Space fasteners 12"–24" apart. [FGRAT p.16]

Guardrail

ZeAllgrate FRP Guardrail & Handrail

FRP guardrail system geometry and OSHA loading. [ZeAllgrate p.5, §7.9]

ComponentSpecification
Post2-1/8" × 3/16" square tube
Two intermediate rails1-3/4" × 1/8" flat
Top rail height42" above walking surface
Handrail height34"
Post spacing≤ 6′-0" (1829 mm) o.c.
CornersNo post at the corner itself — use two posts within 12" each side
LoadingOSHA 1910.29(b): 200 lb concentrated down/out OR 50 lb/ft uniform on the top rail (not concurrent)
Ladder

ZeAllgrate FRP Fixed Ladder System

Fixed ladder dimensions and code loading. [ZeAllgrate p.6–7, §7.10]

ItemSpecification
Side rails1-3/4" × 1/4" square tube
Rungs1-1/4" diameter × 1/4" fluted
Clear inside width18"
Rung spacing12" o.c.
Wall support≤ 6′-0" (1829 mm)
LoadingOSHA 1910.23; rung 250 lb at midspan; two 250 lb loads between attachments (ANSI 14.3)
Tall ladders≥24 ft require personal fall-arrest / ladder-safety system per OSHA 1910.28(b)(9); drop test 18" / 500 lb per 1910.29(i)
Stair

ZeAllgrate FRP Stair System

FRP stair treads and stringer design. [ZeAllgrate p.11–13, §7.11; FGRAT p.14–15]

ItemSpecification
TreadZeAllgrate FRP stair tread, 1-1/2" deep, 1-1/2" × 6" mesh; panels 22-1/4"×120" and 25-1/4"×144"
Tread deflection limitL/150
Stair live load1000 lb (500 lb per stringer)
SlopeOSHA 30–50°; IBC 20–32.5°; IBC 100 psf uniform, L/D ≥ 180
LandingsEvery 12′ rise
StringersC8 (8" × 2-3/16" × 3/8") or C10 (10" × 2-3/4" × 1/2")

Installation Sequence Overview

StepPractice
1. LayoutOrient bearing bars along the span across the supports; mark cut positions
2. CuttingCarbide blade or abrasive saw; clean square cuts; deburr edges
3. OpeningsFabricated or field cut-outs edge-sealed; reinforce per the cutting guide
4. SeatingFull bearing on supports; minimum seating width per design
5. ClippingClip pattern per the drawing (corners + mid-span); torque snug, not tight
6. GapsThermal movement gaps; one fixed end per run
7. AcceptanceWalk the deck; verify orientation, bearing, clips and gaps; retorque after first week

Common Installation Errors

  • Rotated panels — bearing bars must run along the span; a rotated panel loses capacity.
  • Over-torqued clips — crushes the laminate; use a torque wrench, snug not tight.
  • Missing mid-span clips — the pattern is corners plus mid-span, not corners only.
  • Free overhang beyond the last support — never cantilever past the hold-down limit.
  • Hard butting with no gap — thermal movement needs a nominal 10 mm gap.

Need a Full Installation Drawing Package?

ZeAllgrate supplies clip schedules, support layouts and accessory lists (angle clips, adjustable pedestals) with every order, plus remote on-site guidance.

Source: ZeAllgrate Guidelines for the Engineer & Designer, Part No. 884305-9/18 ©Industry reference 2018 [ZeAllgrate] §7.1–§7.11; clip hardware and sealing [FGRAT p.15–17]. All spacing, bolt and load values transcribed verbatim.