Farrat is a specialist engineering company that manufactures solutions for vibration control, thermal isolation and precision levelling applications in the global construction, industrial and power generation sectors. We produce structural and acoustic vibration isolation systems, thermal break connections and machine levelling mounts as well as other ancillary products serving a variety of end user applications. Our multi-disciplinary team encompasses mechanical, structural, acoustic and construction engineering specialists and is backed up with 50 years of technical expertise. We work closely...

Acoustic Floating Floor Systems

Farrat Floating Floor Systems Introduction Welcome to Farrat’s guide to high-performance, acoustic floating floors. We have prepared this brochure to serve as a resource for architects, acoustic consultants and structural engineers to assist when designing and specifying spaces where vibration control or high levels of sound insulation are required. Whether you use this brochure to gain a basic understanding of the concepts involved in the different types of floating floors or use the technical data provided to design bespoke systems, Farrat’s team of specialist engineers are on hand to provide...

Why choose Farrat Acoustic Floating Floors? Farrat’s Isomat and Jack-Up floating floors... ❫ Are used in a wide range of buildings to protect sensitive areas from noise sources or to contain noise sources within their areas ❫ Offer flexibility in delivery as well as being easy, fast and economical to install ❫ Provide a high degree of impact, shock and vibration control through a combination of mass addition and structural decoupling by constructing the floating slab on elastometric or coil spring isolators tuned to specific frequencies ❫ Provide a high degree of airborne noise isolation through...

Floating Floor VariantsElastomeric or Coil-Spring Isolators? Each of the options on this page are available with elastomeric or coil-spring isolators. Coil-spring isolators are more expensive than elastomeric ones, however allow for higher performance from lightweight floating elements. Floating floor performance is achieved by extra mass in the floating element. Such floors are more economical than Jack-Up floors and create a full area, homogenous slab with minimal flanking. H Concrete or screed | Plywood: 15mm H Isolation zone: 37-200mm with mesh or fibre reinforcement: Perimeter isolation:...

KEY: Screed: 100-400mm Pre-cast concrete planks: 50mm Isolation zone: 80-300mm Packer: as required Mesh reinforcement loops Pre-cast system is formed by combining pre-cast concrete planks spanned between steel beams with a concrete or screed top layer. This makes it possible to create very high performance floating floors which can take very high loads with minimal supporting points. SEE PAGE 18 Jack-Up floating floors comprise of a concrete slab which is poured on a damp proof membrane on the structural slab. The slab is then 'jacked’ up by way of units cast into the slab. They are favoured...

Isolator Specification Fig 8.1 Construction For loads considered in the above table, ADL = DL + 33% LL, LL = 5kN/m2 Notes on Acoustic Performance ) Configurations based on a 12m x 6m room with 75mm x 75mm x 50mm elastomeric isolators at 600mm centres and 90 x 55 x 63mm spring isolators at 400mm centres. ) Some available test values are only “predicted from test results” rather than directly tested as the performance of our products was too high for the laboratory to test at some frequencies. ) Further acoustic data is available on request. Site test data is available to validate predictions....

Isolator Properties KEY (all graphs p9) Static Compression Modulus 1.3 Dynamic to Static Ratio 1.2 Max Static Pressure [Overload] (N/mm2) 0.26 [0.39] Creep Minimal Operational Life (years) 60 Static Compression Modulus 2.0 Dynamic to Static Ratio 1.5 Max Static Pressure [Overload] (N/mm2) 0.40 [0.60] Creep Minimal Operational Life (years) 60 Static Compression Modulus 3.5 Max Static Pressure [Overload] (N/mm2) 0.70 [1.05] Creep Moderate Operational Life (years) 60 COIL SPRINGS Farrat Isolator OSI 75-63 OSI 100-63 OSI 125-83 Spring Constant (kN/mm)...

Design Considerations Supporting Walls on Floating Floors Where walls are to be built off a floating floor, it is usually necessary to increase the isolator area or decrease the spacing of the pads to provide support for the additional line load of the wall. Using this method, any wall types, even dense blockwork can be supported by the floating floor without compromising the acoustic performance. A quicker and cheaper alternative to supporting walls on a floating slab is to separately isolate them using Farrat FAVIM stud isolation strips and AWTH washes. A very high level of sound insulation...

Mineral Wool in Floating Floors The acoustic performance of our floating floor systems is so high that incorporating mineral wool in the cavity only has a very small effect on the overall sound insulation. However mineral wool can play an important factor in boosting the low frequency performance of a lightweight floating floor. Under most circumstances, having 50% of the cavity filled with mineral wool increases the airborne and impact sound insulation by 1dB (in terms of overall Rw). When the cavity is 100% filled, this increases to 2dB, however for lightweight floors a performance increase...

Air-Gap Stiffening When the volume of air in the cavity is low in relation to the surface area of the floating element above it, a phenomenon occurs called 'air-gap stiffening'. As the floating element vibrates, it compresses the air in the cavity, which causes it to behave more like a solid than a gas. In small rooms, the effect is generally negligible, however in large rooms, the effect can significantly undermine the acoustic performance of the floor. The results of our acoustic testing show that air-gaps less than 35mm should be avoided to reduce the likelihood of encountering air-gap stiffening unless...