GB2219015A

GB2219015A - Sound attenuating flooring system

Info

Publication number: GB2219015A
Application number: GB8812201A
Authority: GB
Inventors: R Robin Kenneth Mackenzie
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-05-24
Filing date: 1988-05-24
Publication date: 1989-11-29
Also published as: GB8812201D0

Abstract

A floating raft floor on top of concrete slab or timber joist structural floors is designed to attenuate the transmission of both airborne and impact sound. This system comprises chipboard or timber flooring 4 laid upon and nailed or screwed to a series of timber battens to which laminated closed 7 and open cell 6 foam strips have been bonded. The open cell structure of the open cell foam 6 permits the attenuation of acoustic energy in the cavity between the battens by dissipation within the interstices of the foam itself. The open cell structure of the open cell foam also allows air contained within the interstices to be expelled under dynamic load and thus permits a proportionately high vertical deflection in relation to the thickness of the material to be achieved. In addition to the airborne sound attenuation properties, the floor also provides the resilience necessary to isolate impact sound from being transmitted into the structural floor. The battens 5 may be laid on a timber sheet 3 supported on joists 2. <IMAGE>

Description

DESCRIPTION SOUND ATTENUATING FLOORING SYSTEM This system involves a design of floating raft construction for laying on top of concrete slab or timber joist structural floors.

Raft type floor arrangements are a common design detail especially in domestic flatted construction where the Building Regulations require a standard for airborne and impact (footsteps) sound insulation to be complied with. Several methods of providing adequate attenuation to the transmission of impact sound have been achieved in the past by the use of mineral wool or glass fibre quilt placed underneath the timber battens associated with the raft construction. Similarly, strips of closed cell polyethylene or polyurethane foam have been used underneath the battens also to attenuate impact sound.

This system is designed to attenuate the transmission of both airborne and impact sound.

This system comprises chipboard or timber flooring laid upon and nailed or screwed to a series of timber battens to which open cell foam material laminated to closed cell material has been bonded.

The open cell structure of the open cell foam permits the attenuation of acoustic energy in the cavity between the battens by dissipation within the interstices of the foam itself. Thus the system contributes to the airborne sound attenuation property of the overall floor design.

The open cell structure of the foam also allows air contained within the interstices to be expelled under dynamic load and thus permits a proportionately high vertical deflection in relation to the thickness of the material to be achieved.

Reference is now made to the accompanying drawings, wherein: - Figure 1 is a diagrammatic sectional view of the flooring system laid upon a concrete structural floor 1.

Figure 2 gives a similar view of the floor laid upon a timber joisted floor 2.

Figure 3 give a similar view of the floor laid upon a timber joisted floor 2 with intermediate timber sheeting 3 between the joists and battens.

By way of illustration but not of limitation, the chipboard flooring 4 is 18 mm thick and the timber battens 5, are 50 mm wide x 28 mm deep. The battens are spaced at 400 mm centres. The open cell foam 6 is 50 mm wide and 12 mm deep and laminated to the closed cell foam 7. The open cell or closed cell foam may be positioned below and bonded to the underside of the timber batten.

Acceptable physical characteristics of the open cell foam would include a density of 10 - 50 kg/m 3 and a tensile strength of not less than 50 kN/mZ.

Claims

1. A sound attenuating flooring system comprising chipboard or timber flooring nailed or screwed to timber battens to which open and closed cell foam strips are bonded to the underside of the batten in order to absorb airborne sound and to isolate impact sound incident upon the floor.

2. A sound attenuating flooring system according to Claim 1 wherein one of the two foam strips are manufactured with an open cell characteristic.

3. A sound attenuating flooring system according to Claim 2 wherein the foam has a density of 10 - 50 kg/m3.

4. A sound attenuating flooring system according to Claim 3 wherein the open cell foam has a vertical static deflection under load of between 4 mm and 24 mm for a compressive stress of 8000 Pa.

5. A sound attenuating flooring system according to Claim 4 wherein the open cell foam has tensile strength of not less than 50 kN/m 2.

6. A sound attenuating flooring system constructed substantially as herein described with reference to the accompanying drawings.

7. A method of constructing a sound attenuating flooring system comprising chipboard or timber flooring nailed or screwed to timber battens to which foam strips are bonded to the underside of the batten in order to absorb airborne sound and to isolate impact sound.

8. A method of constructing a sound attenuating flooring system substantially as herein described with reference to the accompanying drawings.