Sprung floor

Sprung floors are a type of floor construction used for activities such as dance, indoor sports, and multi-purpose halls where specific properties of shock absorption and energy return are desirable to reduce the occurrence of injuries that may result from repeated impact or falls. They can also help maximise performance.

The first sprung floors were developed in the 1870s, but they did not become popular until the 1920s, when American dancehalls began to install wooden floors supported on metal springs.

Sprung floors are designed to provide have optimum characteristics consistently across their surface, tailored to the specific needs of the activity that will be performed on them. For example, whilst sport may be tailored to properties such as ball bounce, dance may be more concerned with shock absorption.

Their characteristics will depend on the construction of the subfloor and the performance of the surface.

They are generally ‘floating floors’, that is, the sprung floor construction is not fixed to the layer beneath it. Elements of the flooring may be fixed to one another, but they are not fixed to the substrate below.

Typically they comprise a damp-proof membrane, two layers of a flexible material laid so that the joints do no coincide, and a top layer of flooring which will typically be vinyl, engineered timber or a hardwood such as maple, beech or oak.

A more traditional ‘basket weave’ construction consists of at least three layers of flexible battens laid at right angles to one another, with the top layer laid across the mid-point of the span of the layer beneath. It is the flexing of this mid layer under load which creates the sprung effect. The effect may be increased by additional layers of battens, or by the inclusion of flexible pads beneath the bottom layer.

A temporary or portable sprung floor can be created by laying interlocking modular panels in a brickwork pattern so that joints do not coincide.

Typically a depth of 100mm is required for the installation of a sprung floor.

Semi-sprung floors, designed to dampen bounce may be constructed simply from a thick vinyl flooring, or a multi-layer composite flooring.

As well as shock absorption and energy return, sprung floors must be designed not to create a trampoline effect, to have adequate slip resistance and traction, and to have appropriate acoustic properties. The acoustic properties required will depend on the activities to be accommodated, for example, ballet as opposed to tap dance.

[edit] Related articles on Designing Buildings Wiki

• Floating floor.
• Flooring defects.
• Floor definition.
• Flooring.
• Plenum.
• Raised floor.
• Separating floor.
• Subfloor.
• Suspended ceiling.
• Suspended timber floor.
• Types of floor.
• Underfloor air distribution.
• Wall types.