British Gypsum Systems Guide: Gyproc Partitions, Linings and Ceilings — System Numbers, Build-Ups and Performance Data

Summary

British Gypsum is the UK's largest drylining manufacturer and the dominant brand in the UK trade. Their Gyproc range defines the vocabulary of drylining: GypWall for partitions, GypLyner for wall linings, GypLyner IWL for insulated wall linings, and GypCeiling for suspended systems. Understanding the system numbering and build-ups is essential for specifying correctly and pricing accurately.

Each system in the British Gypsum portfolio has been tested to EN standards and carries published performance data. Unlike site-mixed solutions, specified systems carry manufacturer backing for compliance — important when building control asks for evidence of fire or acoustic performance. Specifying "British Gypsum GypWall CLASSIC 70/75 C with 2 × 15mm Gyproc FireLine" gives building control a traceable, tested system.

The White Book (British Gypsum's Technical Manual) is the definitive reference. It is available free online and updated regularly. System references in this article reflect the 2024 edition — always check the current White Book for the latest data, as system designations can change with new product launches or updated test data.

Key Facts

• White Book — British Gypsum's Technical Manual; free online, searchable by performance requirement. The starting point for any system specification.
• GypWall CLASSIC — standard metal stud partition family; studs at 48, 60, 70, 92, or 146mm depth; track at corresponding depth
• GypWall QUIET — acoustic-optimised partition with resilient hangers and acoustic quilt; higher Rw than CLASSIC at same stud depth
• GypWall ROBUST — heavy-duty partition for high-traffic areas; double-layer boards, reinforced fixing zones
• GypLyner UNIVERSAL — direct-bonded (dot-and-dab) wall lining system; 25mm minimum plasterboard, DriWall Adhesive
• GypLyner IWL — insulated wall lining for external walls; PIR boards laminated to Gyproc; reduces thermal bridging
• GypCeiling MF — metal furring ceiling; independent suspension for acoustic and fire performance
• GypCeiling FLOOR — ceiling system tested in conjunction with concrete or timber floor above for Part E compliance
• Board weights — Standard 12.5mm Gyproc WallBoard: 8.5 kg/m²; 15mm FireLine: 11 kg/m²; 25mm SoundBloc: 22 kg/m²
• Fire ratings — published as EI (integrity/insulation) in minutes; 15mm FireLine single layer typically achieves EI 30; double layer achieves EI 60
• Acoustic ratings — published as Rw (weighted sound reduction index) in dB; higher = better
• Stud centres — typically 600mm for standard linings; 400mm for heavy tile loads or high boards
• Board orientation — horizontal laying ("brick bond") increases wall stiffness; vertical laying is faster but lower performance
• Screw type — Gyproc TwinFast or bugle-head drywall screws; length = board thickness + 10mm minimum into stud
• Joint treatment — Gyproc Jointing Compounds: EasiFill (filler), Topping Compound (feathering), Gyproc Joint Tape (paper or fibreglass mesh)

Quick Reference Table

Always verify figures in the current British Gypsum White Book — figures above are indicative only

Detailed Guidance

GypWall CLASSIC — Standard Partition Build-Up

GypWall CLASSIC uses galvanised steel C-stud (CW profile) and UW track. The system number incorporates the stud width: CLASSIC C (70) means 70mm C-stud. The full system designation format is:

GypWall CLASSIC [variant] [stud width]/[stud depth] [board configuration]

Example: GypWall CLASSIC C 70/75 2×12.5 WallBoard + 100mm acoustic quilt

Installation sequence:

1. Fix UW track to floor and ceiling using Gyproc Track Screws at 600mm max centres; apply acoustic sealant between track and structure
2. Insert CW studs at 600mm centres (400mm for boards over 2.4m high or tile fixing)
3. Stagger board joints — no joint should align on both sides of the partition
4. Fix boards using TwinFast screws at 230mm centres in the field, 150mm at perimeters
5. Fill the stud cavity with Isover or Knauf acoustic quilt (50–100mm, unfaced) for acoustic performance
6. Tape and joint all joints with Gyproc Joint Tape and compound
7. Apply perimeter acoustic sealant at all abutments

The board-to-stud connection is critical for acoustic performance. Loose screws or missed fixings create flanking paths. Check each screw pulls flush without breaking the board face paper.

GypWall QUIET — Acoustic Partition System

GypWall QUIET uses resilient metal hangers (GyprFrame or similar) that decouple the boards from the stud. This breaks the rigid connection that transmits sound. The system can achieve up to 64 dB Rw — well above the Part E 45 dB minimum for separating walls in new dwellings.

Key differences from CLASSIC:

• Resilient channels fitted horizontally to CW studs at 400mm centres (vertical boards) or 600mm (horizontal boards)
• Boards screwed only to resilient channels, NOT through to the stud
• Acoustic sealant at all perimeters, junction boxes, and service penetrations
• Sockets on opposite sides of the partition must be offset by minimum 150mm (horizontally) to avoid creating flanking flanking paths through back-box cavities

The resilient hanger is the performance-critical component. Using standard furring channel instead of the specified resilient hanger will dramatically reduce acoustic performance — sometimes by 10–15 dB.

GypLyner IWL — Insulated Wall Lining

GypLyner IWL consists of Gyproc wallboard factory-bonded to PIR insulation. It is applied direct-bonded (dot-and-dab) to the external wall, eliminating the need for a separate insulation layer and reducing the number of site operations.

Thermal performance varies by insulation thickness:

• 25mm PIR + 12.5mm board: λ ≈ 0.022 W/mK contribution; reduces wall U-value by ~0.35 W/m²K (depends on base wall)
• 50mm PIR + 12.5mm board: greater contribution; suitable for solid brick walls where U-value improvement is needed to comply with Part L Table 4

Installation requirements:

• DPC level: bottom of boards must be at or above DPC level — never below. If the floor is below DPC, return the lining up from finished floor level.
• Adhesive dabs: minimum 250mm × 50mm dabs at 300mm vertical centres; perimeter bonded at 75mm from edges
• Service voids: electrical conduits can be run in chases in the insulation layer before boarding; 50mm maximum depth
• Airtightness: tape all board-to-board joints and perimeter junctions with Gyproc Air Sealing Tape for Part L compliance

GypCeiling MF — Metal Furring Ceiling System

GypCeiling MF uses galvanised main runners (MR24 or similar) suspended from the structural soffit on wire hangers, with secondary furring channels (FC47) spanning between them. Plasterboard is fixed to the furring channels.

Hanger spacing: maximum 1.2m along the runner; maximum 1.5m runner-to-runner centres (check current BG data as load tables apply).

Levelling procedure:

1. Mark ceiling height on all four walls using a laser level
2. Fix perimeter angle to walls at the ceiling level using appropriate fixings for the substrate
3. Run primary runners parallel at 1.2m maximum centres, suspended to within 150mm of walls
4. Tension hanger wires to level (laser or string line); wire clipped to runner with pressed hanger
5. Fit secondary furring channels at 600mm centres (400mm for 2-board configurations), cross-checking with level

The system can be independently suspended well below the structural soffit — 500mm+ drop is achievable for running services above the ceiling.

System Selection for Part B (Fire)

For fire-rated partitions and ceilings, the system must match the tested configuration exactly:

All penetrations (pipes, cables, ducts) must be fire-stopped to maintain the fire rating. Intumescent products must be specified and installed per their approval data.

Board Selection Quick Guide

Frequently Asked Questions

Can I mix British Gypsum boards with other brands of stud?

Technically yes — the boards are a separate product from the metal stud. However, the fire and acoustic performance data in the White Book applies to the complete tested system, including the British Gypsum stud. If you substitute a different manufacturer's stud (different profile depth, thickness, or perforation pattern), the performance cannot be guaranteed to match the published figures. For non-critical applications (residential linings, non-fire-rated partitions) mixing brands is commonplace. For fire-rated or Part E compliant separating elements, use the complete tested system from a single source.

What's the maximum height for a standard GypWall CLASSIC 70mm stud partition?

Stud height capacity depends on stud width, stud gauge, and fixing restraint. For 70mm × 0.6mm gauge CW stud at 600mm centres, the British Gypsum White Book gives a maximum height of approximately 3.6m for single layer boards. For heights up to 4.5m, increase to 92mm or 146mm stud, or use 0.9mm gauge. Above 4.5m, deflection heads and bracing are required — see drylining floor to ceiling heights for full guidance.

Does British Gypsum offer a complete ceiling-floor acoustic tested system for Part E?

Yes. GypCeiling FLOOR systems are tested with specific floor constructions above. The White Book includes combined performance data — the critical figure is the Dn,T,w + Ctr value which must meet 45 dB for separating floors in new dwellings (Part E Table 1a). Always specify the complete tested assembly (floor construction + ceiling build-up) rather than treating them separately.

Where do I find the current system reference numbers?

The British Gypsum White Book is available free at uk.bgyp.com. The online version is searchable by performance requirement (e.g. "60-minute fire", "50 dB Rw") and returns current system references. The printed copies become out of date — always use the online version for specifying work.

Regulations & Standards

• Building Regulations Approved Document B (2019 edition, 2020 amendment) — fire resistance requirements for partitions and ceilings in dwellings and other buildings

• Building Regulations Approved Document E (2003, as amended 2015) — sound insulation requirements; Rw + Ctr thresholds for separating walls and floors

• Building Regulations Approved Document L1B/L2B — conservation of fuel and power; U-value targets for linings on external walls

• BS EN 520:2004 — gypsum plasterboard specification; types A (standard), H (moisture resistant), F (fire resistant), P (for plastering)

• BS EN 14195:2014 — metal framing components for gypsum board systems

• BS EN ISO 9972:2015 — air permeability testing (blower door test) — relevant for airtight drylining installations

• BS EN ISO 717-1:2013 — acoustics; rating of sound insulation (defines Rw and C, Ctr adaptation terms)

• British Gypsum White Book (current edition) — system performance data; design and installation guidance

• British Gypsum White Book — complete system specifications, installation guides, and performance data

• HSE Construction: Drylining — health and safety for drylining operatives

• CITB Drylining NVQ — qualification framework for drylining trades

• Building Regulations Approved Document E — Part E compliance requirements

• metal stud partition installation — detailed installation procedure for CW/UW systems

• building regs part e acoustic — Part E acoustic compliance routes and required performance levels

• building regs part b fire lining — fire resistance requirements and how to achieve them with drylining

• drylining floor to ceiling heights — stud sizing and bracing for high partitions