Standard plasterboard partitions: sizing and multi-trade interface
4 critical interfaces: sizing 72-120 mm
The standard plasterboard partition is not a materials question, it is a coordination question: in our experience, the majority of malfunctions identified stem from interface errors between trades, not from defective boards or framing. The DTU and NF S 31-080:2006 set the framework, but delivered performance depends on coordination between the drywall installer, the electrician and the HVAC team. Kytom applies a 5-phase methodology, with a target acoustic insulation of Rw >= 32 dB and a typical execution time of around one day per linear metre depending on site complexity. This page sets out the method, the 4 critical interfaces and the ratios observed across 1200+ projects completed since 2006.
Sizing a standard plasterboard partition arbitrates between four structuring criteria, ranked by use:
- Acoustic performance: Rw >= 32 dB for enclosed offices, Rw >= 38 dB directionally for spaces requiring enhanced confidentiality.
- Mechanical resistance: wall loads (screens, shelves) requiring frame reinforcements at installation.
- Network routing: high- and low-voltage currents, with chasing prohibited by the DTU.
- Installation height: 4 m maximum with single M48 framing, beyond which reinforced framing is used.
These trade-offs determine the final thickness: 72 mm minimum for standard dividers, 98 mm for demanding enclosed offices, 120 mm for confidential meeting rooms. The classic mistake is to size solely on the acoustic criterion while neglecting future loads. Our field experience distinguishes three sizing scenarios: individual offices (loads 60 kg/lm). This grid avoids over-sizing and guarantees functionality at 5-10 years.
When the plasterboard partition is not the right answer. Below 200 m2 of partitioning with more than 2 reconfigurations expected over 5 years, the dry partition is not cost-effective compared with a removable partition (requiring demolition then reconstruction with each move). Above a continuously required Rw >= 50 dB (confidential laboratories, trading floors), plasterboard lining alone reaches its physical limit: opt for a masonry system or a decoupled double partition. Finally, in permanently humid areas (showers, process rooms > 70% RH continuous), standard plasterboard is ruled out in favour of a water-repellent type such as H1 board.
For the architect and the project manager: size the partition/door/ceiling system, not the partition alone
From the project management standpoint, the plasterboard partition is only a component: what is delivered to the end client is an acoustically and mechanically performant volume. The standard configurations encountered in French office space can be summarised as follows:
| Type | Thickness | Framing | Target Rw | Use |
|---|---|---|---|---|
| Standard divider | 72 mm | M48 single | 32 dB | Corridors, circulation areas |
| Enclosed office | 98 mm | M48 + 45 mm wool | 38 dB | Individual workstations |
| Meeting room | 120 mm | M70 + double facing | 44 dB | Standard confidentiality |
| Confidential room | 120 mm + lining | M70 + 70 mm wool | >= 50 dB | Management, HR |
Three points of caution accompany this table. First, actual insulation depends on the perimeter junctions: a poorly treated joint can significantly degrade the measured Rw, sometimes by several decibels. Next, acoustic doors limit overall performance to the DnTw of the leaf (28 to 38 dB as standard, manufacturer values verified at handover). Finally, absorbent suspended ceilings with an aw coefficient of 0.80 to 1.00 per NF EN ISO 11654 complete the arrangement in open-plan spaces to target 35 to 40 dB(A) of ambient noise. Our reading differs from common practice on this precise point: prescribing a Rw 44 dB partition without checking the door’s DnTw or the ceiling absorption is sizing a chain by its strongest link. Kytom sizes the partition, door and ceiling assembly as a coherent system, never component by component.
Common tensions: 3 recurring errors and coordination phasing
Three errors regularly compromise delivered performance, identified across our portfolio of recent projects:
- Insufficient reinforcements for heavy fixings (32-inch screens, interactive whiteboards), addressed after installation and therefore ineffective.
- Defective electrical coordination: unauthorised drilling after installation that destroys acoustic sealing.
- Neglect of perimeter joints: sound bridges at floor, ceiling and facade junctions.
These defects stem from inappropriate phasing. Cable routing must be defined before framing, reinforcements positioned during assembly, never after boarding. Best practice requires a dedicated coordination meeting bringing together the drywall installer, the LV/ELV electrician, the fluids engineer and the fit-out manager. This session validates the final layouts, identifies reinforcement zones and plans interventions sequenced by trade. The Kytom method integrates this coordination from the design stage: BIM modelling of critical interfaces, detailed planning by milestone. Internal feedback shows that formalised phasing significantly reduces site rework.
Limits of the formalised multi-trade approach. On operations < 150 m2 with a single trade active at any one time, the dedicated coordination meeting consumes more time than it saves: a written brief is sufficient. Conversely, beyond 6 concurrent trades on the same floor plate, the meeting format reaches its limit and must switch to continuous BIM management with a shared model.
Kytom’s 5-phase method: audit, sizing, coordination, execution, control
The methodology is structured in five linked phases, each producing a contractual deliverable:
- Constraints audit: analysis of planned loads, mapping of existing networks, acoustic survey of the site.
- Technical sizing: calculation of framing and lining according to target performance, signed sizing sheet.
- Preliminary coordination: multi-trade meeting to validate interfaces, coordination plan circulated within 48 h.
- Sequenced execution: framing assembly, network routing, boarding, in this strict order.
- Final control: acoustic verification (DnTw measurement compliant with applicable standards), stability, handover report.
The phasing respects drying times (24 hours minimum between coats of filler) and incorporates access constraints (minimum width of 80 cm for handling 1200 x 2500 mm boards). The design and build approach unifies responsibility: design and execution follow the same technical logic, eliminating decision-making breaks between project management and the contractor.
Frequently asked questions
What thickness of plasterboard partition for an enclosed office?
98 mm with M48 framing and 45 mm mineral wool to achieve Rw >= 38 dB. This configuration meets the common acoustic requirements of individual offices in commercial buildings. For higher requirements (management, HR), move to 120 mm with M70 framing and double facing.
What reinforcements should be planned for heavy wall fixings?
A significant portion of the partition’s linear length requires frame reinforcement depending on the nature and density of the planned fixings. For loads of 30-60 kg/lm (screens, shelves), timber or sheet-metal cross-members are integrated into the framing during assembly, never after boarding.
