Home » Solutions » Non-Residential Building » Internal Walls - Partition

Internal Walls - Partition

Overview

The use of framed lightweight partitions to subdivide a building's space is fast and effective. These partitions are generally required to provide acoustic insulation. A specific fire or impact resistance may also be required.

Lightweight partitions are used in all types of commercial buildings, including offices, hospitals, schools, shops and cinemas.

Advantages

Using glasswool as a sound absorbent layer in partitions will significantly improve the acoustic performance of the partition, whilst only adding minimally to the overall mass of the structure.

The glasswool complements the plasterboard by absorbing airborne sound in the cavity and reducing reverberation. It also has the effect of reducing the hollow sound that can occur in partitions with unfilled cavities.

Additionally, using a glasswool infill will improve the thermal insulation achieved by the partition. Whilst there is no requirement in the Building Regulations for these walls to provide thermal insulation, it could be a desirable feature helping to control the energy usage in large buildings.

Knauf Insulation Products

TP 116 is semi rigid, unfaced batt of glasswool specifically designed for friction fitting.
Classic 040 is a roll of unfaced glasswool, available in a range thicknesses which cab be used in partition walls.
TI 216 / TI212 is a flexible, resilient roll of glasswool faced with a kraft paper/polythene laminate on one side. The facing is wider than the insulation to provide a fixing flange on each side.

Summary

Knauf Insulation provide products for a range of partition systems, giving options that will comply with client requirements.

Detailed Design Considerations

Sound Insulation

Sound insulation, otherwise known as sound reduction, is the prevention of noise being transmitted from one part of a building to another, for example by erecting a partition.

The Sound Reduction Index (SRI) of a building element describes the resistance of that element to airborne sound transmission. This is usually expressed as R_w dB.

When considering sound insulation between adjacent rooms in a building, airborne sound is the main concern for designers.

Airborne Sound

Airborne sound sources produce noise by vibrating the air immediately around the sound source. Typical sources include the human voice, televisions, musical instruments, traffic and sound systems.

The ability of a partition to resist the passage of airborne sound energy through it is largely determined by four factors:

The sound absorbency of any cavities in the construction
The mass of the construction
The degree of structural isolation between the two outer surfaces
The air tightness of the construction

Sound Absorbency

The sound absorption characteristics of glasswool make it ideal for use in partitions to assist in absorbing sound within a cavity.

Increased Mass

Increasing the thickness, weight and number of plasterboard layers improves the sound insulation of a partition by increasing its mass. Knauf produce a range of performance plasterboards, including special acoustic plasterboard. This has a significantly higher mass than standard plasterboard and is used to improve the sound insulation of partitions.

Increased Isolation

Where high acoustic performance is required, constructing the partition with twin studs provides the maximum degree of isolation between the two faces of the partition. Staggered studs can also be used where partition width is limited.

Quality of Detailing

A construction can only achieve its expected sound performance if it and the surrounding walls and floors have no inherent faults in their detailing or workmanship. Performance will be impaired if:

There are gaps or holes in the construction – even hairline cracks can seriously impair sound insulation. Seal all potential gaps with a flexible sealant.
There are gaps in the absorbent layer within the cavity.
To minimise coincident joints in the
A partition stops at the underside of a suspended ceiling, as sound can transfer from one room to another via the ceiling void.

Commercial Partitions - Acoustic Guide

Room type	Weighted sound reduction index (R_w dB)*
General office	38
Private office	44
Executive office	50
Cinemas	60

* From laboratory test results Source: BS 5234: 1992

Fire Performance

Glasswool is classified as noncombustible and hasd unbeatable A1 Euroclass

The use of glasswool helps to improve the fire rating of a partition by limiting the radiation of heat across the cavity.

For fire rated partitions, Knauf produce special fire resistent plasterboard. This offers superior fire protection to standard wallboard.

Thermal Insulation

Whilst thermal insulation is not generally a requirement of partitions, it may be desirable in certain circumstances. For instance, a computer server room that needs to be kept at a low temperature would benefit from enclosing partitions with mineral wool infill. As the need to reduce energy wastage increases, insulated partitions would make zoned heating within a building more feasible.

Typical Specification Clauses

1) Standard Metal Stud Partitions

In all …... (steel stud) partitions install acoustic insulation TP116 …...mm thick. Secure TP 116 at head of partition using timber batten or light steel angle. Insulation to fit snugly between studs and at bottom of the structure to ensure that there are no air gaps. Seal partition at perimeter and all service penetrations with an acoustic sealant.

2) Staggered Stud Partitions

In all …... (steel stud) partitions install acoustic insulation TP116 …...mm thick.

Once the studs have been positioned and one side boarded out, the insulation to be wound through the studs horizontally. Ensure there are no gaps at abutments or between adjacent lengths of the insulation.

Seal partition at perimeter and all service penetrations with an acoustic sealant.

3) High Performance Twin Frame

In all …... (twin frame) partitions install acoustic insulation TP 116…...mm thick.

Once the studs have been positioned and one side boarded out, the insulation to be inserted between the studs horizontally. Ensure there are no gaps at abutments or between adjacent lengths of the insulation.

Seal partition at perimeter and all service penetrations with an acoustic sealant.