Gypsum Systems

Gypsum Systems

  • 1. Introduction
  • SpecX quick selector
  • 2. Main gypsum product types
  • 3. Framing and suspension systems
  • 4. Performance parameters
  • 5. Typical assemblies (examples)
  • 6. Application guidance and installation best practices
  • 7. Common failures and remedies
  • 8. QA / QC checklist
  • 9. Sample BOQ lines
  • 10. Standards and references

1. Introduction

Gypsum is a lightweight, dimensionally stable board system used for ceilings, dry partitions, linings and decorative features. It’s non-structural, easy to install, and provides fire & acoustic options with the right board type and assembly.

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SpecX quick selector

  • Office partition (STC ≥ 45): 2 × 12.5 mm gypsum each side + 50 mm studs + 50 mm mineral wool, sealed perimeters
  • Fire-rated shaft (60/120 min): 2 × 15 mm fireboard each side, tested assembly, fire-stopping at penetrations
  • Suspended ceiling: GI exposed grid + 12.5 mm board, deflection L/360, acoustic infill where required

Gypsum is a lightweight, dimensionally stable board system used for ceilings, dry partitions, linings and decorative features. It’s non-structural, easy to install, and provides fire and acoustic options with the right board type and assembly.

2. Main gypsum product types

  • Standard gypsum board (GKB) — general purpose boards for dry interiors.
  • Moisture-resistant (Green/MR) gypsum board — used in bathrooms, kitchens (limited exposure).
  • Fire-rated gypsum board (Type F / WR) — gypsum with glass fiber or additives; used for fire-rated enclosures.
  • Sound-rated or acoustic boards — denser boards or assemblies with acoustic layers.
  • Moisture and mold-resistant specialty boards — for humid environments (verify with supplier).

3. Framing and suspension systems

  • GI studs and channels (studded partitions): typically 50 or 75 mm studs with double channels.
  • Ceiling grid systems: exposed or concealed T-bar systems (metal grid).
  • Screw fixings and jointing: recommended fastener spacing (edge and field), jointing compound, tape.

4. Performance parameters

  • Board thickness: 9 mm, 12.5 mm, 15 mm common.
  • Fire rating: 30, 60, 90, 120 minute assemblies depend on board and layers.
  • Acoustic STC: depends on stud spacing, insulation and board layers (e.g., STC 45–55 for partition assemblies).
  • Deflection limits: ceilings typically L/360; check manufacturer for long spans.

5. Typical assemblies (examples)

  • Office partition STC 45: Double 12.5 mm gypsum each side + 50 mm stud + mineral wool 50 mm.
  • Fire-rated shaft: 2 × 15 mm fireboard each side + special framing + fire seals and intumescent tapes.
  • Standard suspended ceiling: GI perimeter channel + main runners + cross tees + 12.5 mm board; acoustic infill if required.

6. Application guidance and installation best practices

  • Stagger joints; offset every successive board layer.
  • Leave control joints for long runs or temperature swings.
  • Install services before closing cavities; coordinate MEP.
  • Seal openings and penetrations with fire-stopping systems where required.

7. Common failures and remedies

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  • Ceiling sagging → spans too wide or moisture ingress; reduce span, add suspension points, use MR boards
  • Joint cracking → poor taping or movement; use proper jointing system and movement joints
  • Mold/efflorescence → persistent moisture; fix source, switch to MR/special boards, improve ventilation
  • Fire rating compromised → unsealed penetrations or wrong board layering; reinstate tested assembly and fire-stops
  • Board sagging in ceilings — insufficient support or moisture. Remedy: use MR boards or reduce span; add suspension points.
  • Cracking at joints — improper taping or movement. Remedy: use appropriate jointing compound, tape, and movement joints.
  • Mold or efflorescence — high ambient moisture. Remedy: find moisture sources, use MR boards or alternate materials in wet environments.

8. QA / QC checklist

  • Check board batch and MTCs.
  • Frame straightness and plumb check before boarding.
  • Screw pattern and embedment as per manufacturer.
  • Jointing sequence and reinforcement verification.
  • Fire seals and intumescent tapes verification (where required).

9. Sample BOQ lines

  • “Supply and fix 12.5 mm gypsum board on GI metal studs at 600 mm centre to centre including jointing and finishing — m².”
  • “Provide exposed grid suspended ceiling system with 12.5 mm boards and acoustic infill — m².”

10. Standards and references

  • IS 2095 — Gypsum boards and related standards (India)
  • ASTM C840 — Application of gypsum boards
  • EN 520 — Gypsum board types (Europe)
  • Fire testing: BS 476 / EN 13501 series / local fire code