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Extension, Polymer Concrete, 24" x 36" x 8" – PG2436EA08 – Quazite

Extension, Polymer Concrete, 24" x 36" x 8" – PG2436EA08 – Quazite

Quazite Box Extension - 24" x 36" x 8" – PG2436EA08

$1,183.89


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SKU PG2436EA08

The Quazite Box Extension is a high-quality underground enclosure extension engineered from monolithic polymer concrete for superior strength, durability, and performance. Designed to meet ANSI/SCTE 77 certification standards, it provides a reliable, long-lasting solution for utility, electrical, and communication applications. Manufactured by Hubbell, the Quazite line represents a commitment to precision engineering and consistent quality. The box extension is stronger and lighter than traditional concrete, making it easier to handle and install while maintaining exceptional load-bearing capacity. It also offers fire and chemical resistance, ensuring dependable protection in harsh environments. 

Dimensions: 24" W x 36" L x 8" H
Weight: 56 lbs
Spec Sheet: Download >

Frequently Asked Questions

PRODUCT INFO

  • Manufacturer: Hubbell (Pencell/Quazite)

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View our Full Selection of Utility Boxes and Enclosures >

Quazite® Box Extension Guide: An Overview

A Quazite box extension increases the depth of an underground utility enclosure without altering its footprint — ideal when conduit elevations change or grade adjustments are needed. This guide explains how extensions work, their load ratings, and installation best practices.

Quazite Box Extension polymer concrete section
Quazite® Polymer Concrete Extension

What Is a Quazite Box Extension?

Each extension section adds vertical depth—typically 8 inches—to standard Quazite enclosures while maintaining their footprint. These stackable modules, made from polymer concrete (PG series) or fiberglass-reinforced polymer (FRP), provide precise grade adjustments and support conduit alignments during field changes.

Example: For a 24″ × 36″ handhole needing 24″ total depth, stack one 8″ extension on a 16″ base enclosure.

Key Features & Standards

  • Polymer Concrete Strength: High compressive strength with lighter handling than cast concrete.
  • ANSI/SCTE 77 Compliance: Tier-rated for vehicle or pedestrian loads.
  • UL Listed Sizes: Many extensions meet UL standards for enclosure safety.
  • Corrosion Resistance: Excellent against salts, de-icers, and soil chemicals.
  • Modular Design: Open-bottom or solid-bottom options for stacking flexibility.
Quazite brand logo
Quazite® by Hubbell Power Systems

Applications

  • Electrical or telecom utility vault depth adjustments
  • Streetlight and signal handholes needing grade corrections
  • Solar farm conduit transitions and retrofit upgrades

Case Study: Depth Correction Without Re-Excavation

Project: A municipal fiber upgrade discovered two handholes set 6″ too low after final grading.

Solution: Instead of rebuilding, crews added 8″ Quazite extensions (PG2436EA08) matching the 24″ × 36″ footprint. Stacking restored elevation while preserving ANSI Tier 15 load compliance.

Result: No redesign or delay—inspection approved immediately and the vault remained watertight and flush with finish grade.

Installation Tips

  • Compact the subgrade uniformly before stacking.
  • Clean mating edges and ensure full wall alignment.
  • Backfill evenly around all sides to prevent racking.
  • Verify cover bolts seat correctly after adjustments.

Frequently Asked Questions

Do extensions change load rating?

No. When properly stacked with matching Tier-rated components, the overall enclosure retains its certified load class.

Can I use a solid-bottom extension?

Yes. Choose a solid bottom when isolating sections or capping near grade; open-bottom types are for stacking above bases.

Are Quazite extensions compatible across product lines?

They must match the same plan size and material family (e.g., PG polymer concrete with PG series bases).