SonaSpray K-13 Special

Spray-on Acoustic Ceiling & Wall Finish

 See our full range of acoustic decorative finishes from textured to the smoothest available

Spray applied seamless one coat decorative acoustic ceiling finish

  • Easily applied to flat or curved surfaces
  • Reduction of noise reverberation
  • Rain on roof noise reduction
  • Thermal insulation and condensation control
  • K-13 Special acoustic ceiling finish typically provides these features at lower installed prices than fixed panel systems.
  • Build Regs. part ‘E’ & BB93 compliant, to be used to reduce reverberation.

SonaSpray K-13 Special acoustic ceiling & wall finish is spray applied directly to most substrates: concrete / plasterboard / GRP / steel / glass / expanded polystyrene and will maintain its fire rating.
Domes / vaults / profiled / corrugated / flat etc.  Almost any shaped substrate can be sprayed with SonaSpray K-13 Special acoustic ceiling & wall finish.

Carbon neutral - Low Embodied Energy - Good for the Environment - Recyclable


Naturally safe recycled cellulose fibre. Reconstruction of a building may necessitate removal of SonaSpray cellulose fibre acoustic ceiling.  It can be recycled or disposed of as a non-special waste to landfill and your local authority waste disposal will give advice on recycling.

Available in a range of standard colours from stock, SonaSpray K-13 Special acoustic ceiling spray can also be manufactured to the client’s colour requirement [minimum quantity applies].

SonaSpray K-13 Special is a total acoustic ceiling & wall finish system, with in-built treatment for fire and mould resistance; coloured through the full thickness of the coating. Manufacture is accredited ISO 9001:2000 certification.

SonaSpray K-13 Special acoustic ceiling spray was developed for installations where the standard SonaSpray K-13 surface was considered to be too coarse. It has a finer texture and is an attractive surface finish in new build and renovation projects.

Should finer acoustic ceiling & wall finishes be required, please see the rest of the range including the smoothest acoustic ceiling & wall finish available.  The excellent sound absorbing qualities of the SonaSpray range allows designers to utilise smaller areas for effective noise reverberation control and improved ambient sound quality.

SonaSpray K-13 Special acoustic ceiling & wall finish is a popular choice in a wide variety of large spaces such as sports and other large hall facilities, school drama studios, television and sound studios, airports, railway stations, swimming pools and entertainment venues, in fact any indoor space where noise reverberation is a problem.  Patented adhesives provide unequalled bond strength allowing application thickness of up to 32mm in one application (see SonaSpray K-13 for thicker applications).

SonaSpray K-13 Special Installations

St. Paul's Way Community School

Bouygues UK

Throughout the construction of St. Pauls Way Community School in Tower Hamlets, London, Oscar Acoustics assisted Bouygues UK with their acoustic ceiling requirements. Nearly 3,000m2 of SonaSpray K-13 Special was applied to corridors, light wells, balconies and the activity hall resulting in easy compliance with BB93.

SonaSpray K-13 Special was chosen for it's:

  • attractive mid-textured acoustic ceiling appearance
  • speed of installation & competitive price due to spray application
  • great light reflectivity
  • applied directly to concrete slab negating the need for decoration
  • through colour acoustic ceiling product

Following completion of the acoustic ceiling works at St. Pauls Way Comm. School, Bouygues, Operations Director, Chris Stevens expressed his thanks by letter:

"Following the recent installation of 3,000m2 of SonaSpray K-13 Special to the corridors, classroom, activity hall and main sports hall ceilings at St. Pauls Way Community School, Bouygues UK Ltd would like to thank Oscar Acoustics for their hard work in delivering a high standard of work within our programme, for which speed of installation was critical.

Your site teams should be commended on the professional manner in which they conduct themselves; we found them to be extremely helpful and knowledgeable whilst keeping comprehensive day to day records of events.  They kept a 100% health & safety record for the duration of the project, passing unannounced inspections from an independent Health & Safety company organised by yourselves.

We are delighted with the appearance of the finished SonaSpray K-13 Special product and the performance that it provides and so too is our client.  It passed all regulation testing first time..."

To read the whole letter, please go to our website testimonials section.

Dome & O2 Arena, Greenwich, London

When The Millennium Dome made the change into the O2 Dome, there was a need once again for acoustic ceiling and wall treatment in some areas. Oscar Acoustics were already familiar with the Millennium Dome, having undertaken three separate projects for the original exhibition.

For the O2 Dome SonaSpray K-13 Special in Ivory and Dark Grey was applied to the exterior façades of the Art Deco style buildings within the Dome concourse.  The result is an attractive decorative finish combined with excellent noise reverberation controlling benefits, completed ahead of schedule and to the very high standards demanded by the main contractor.

In the O2 Arena music venue, SonaSpray K-13 was applied in black.  The O2 Arena is considered by many artists as one of the finest large music venues for acoustics.

YRM Architects’ Studio, Kings Cross, London

SonaSpray K-13 Special was applied to the pitched soffit in white, contrasting with the recently refurbished original trusses.

Our experienced spray team masked and hand finished to a white trim, creating a definitive edge and preventing colour migration from the beautiful Victorian timber to the new ceiling.

The architects and staff of YRM now have a quiet, comfortable and less stressful environment in which to work.

Harpurhey Leisure Centre, Manchester

 Acoustic design calculations demonstrated there would be a problem with speech audibility in the pool area due to high levels of noise reverberation. Instructors of swimming lessons would find teaching very difficult and the serious problem existed of people misunderstanding the public address system announcements and instructions in the event of an emergency.

Oscar Acoustics were employed to apply 16mm of SonaSpray K-13 Special acoustic ceiling finish to the soffit in white. The installation was completed in 1 week.

The pool environment is reported as excellent and now has the additional benefit of thermal and condensation control.

For more information or to Request a brochure on SonaSpray K-13 Special, call us on 01474 854902 or use our Enquiry Form

SonaSpray K-13 Special Technical Specification

   Download BIM Object

Acoustic DATA:

Where noise reverberation is a problem SonaSpray K-13 special acoustic ceiling and wall finish can be tailored to meet your specific project acoustic needs.  There is a choice of finish; you may select texture, colour and acoustic performance.  SonaSpray K-13 Special acoustic ceiling and wall finish can be applied at variable thickness and variable area to provide a designed acoustic ambience.  It is spray applied to the full thickness in one application.

SonaSpray K-13 Special absorption coefficients

in mm
12.5mm 0.09 0.22 0.58 0.79 0.88 1.04 0.65
16mm 0.10 0.35 0.83 0.88 0.99 1.04 0.75
19mm 0.10 0.35 0.87 0.87 1.03 1.07 0.80
25mm 0.14 0.54 0.93 1.03 1.08 1.05 0.90
32mm 0.18 0.60 0.98 1.03 1.04 1.05 0.90

Test DATA certified by TNO Technical University Delft NL.  SonasSpray acoustic ceiling and wall finish tests were on a solid backing. A panel backing with air space behind the panel will change absorption; normally there is improved absorption at low frequency.


SonaSpray K-13 acoustic ceiling and wall finish achieves M1 certification for Building Materials emissions.   This is the best possible classification. Click here for certificate.

Thermal DATA:

SonaSpray acoustic ceiling and wall finish insulates by creating dead air spaces macroscopically between and within the hollow cellulose fibres. Testing on actual buildings demonstrates that sprayed insulation outperforms fibreglass bats that are mechanically retained.  100mm thick U = 0.32 W/m2K


Dry Weight of SonaSpray Special K-13 per 10mm thickness = 0.90 kg/m2

Wet Weight of SonaSpray Special K-13 per 10mm thickness = 1.72 kg/m2

Dry Weight of SonaSpray K-13 Special per 20mm thickness = 1.80 kg/m2

Wet Weight of SonaSpray K-13 Special per 20mm thickness = 3.44 kg/m2

Bonding to Substrate:

SonaSpray K-13 Special acoustic ceiling and wall finish can be applied to virtually any substrate; some surfaces may need priming to control suction. Old surfaces may need a barrier coating to prevent staining from leaching out contaminants while the surface is wet.  Fully cured SonaSpray K-13 Special will improve strength as well as reducing noise reverberation.

Condensation Control:

For areas such as indoor pools and ice arenas, SonaSpray K-13 Special acoustic ceiling and wall finish aids in not only noise reverberation control but condensation control and cold bridging.  The proper combination of SonaSpray K-13 Special and ventilation prevents condensation on metal, concrete and other similar surfaces. SonaSpray K-13 Special actually reduces ventilation requirements, saving in both the ventilation equipment cost and operating costs.

RH Control:

SonaSpray K-13 Special acoustic ceiling and wall finish is a natural humidity moderator.  At times of increasing humidity SonaSpray K-13 Special will absorb large amounts of water vapour.  When the humidity drops SonaSpray K-13 Special will exhale water vapour and maintain a balance. This characteristic promotes a healthy atmosphere.


The adhesive used with SonaSpray K-13 Special acoustic ceiling and wall finish provides a strong, durable and resilient bond.  When fully cured, surface strength of old plaster will typically improve.

Recessed Items:

Recessed services e.g. spot lighting will require a halo spacer to match the material depth. Oscar Acoustics manufacture and install stainless steel halo spacers to the same size as the hole cut out.  Stop beads may be required around openings which again we can supply and install.  Specially designed access hatches are also available through Profab, enabling the SonaSpray to continue across the hatch door.  Problems can arrise from using other hatches.  These items are at extra cost and are to be purchsed direct from the Profab.  Please contact Oscar Acoustics for details and an item code.  Surface mounted fittings e.g. hanging/pendant lights will require pattresses to match the material depth.  Please contact Oscar Acoustics for further advice.

Where to use:

SonaSpray K-13 Special acoustic ceiling and wall finish can be quickly and effectively applied to any prepared surface and construction configuration where noise reverberation is a problem.  This allows minimum working down time in existing structures with abilities to meet critical deadlines in new construction.  SonaSpray K-13 Special has a medium surface texture and is suited to reducing noise reverberation in large rooms and halls.  When applying to walls, position acoustic finishes above head height.  For lower walls or areas of high impact, see EchoCheck acoustic blocks or Oscar Evo-Panels.

Other SonaSpray products offer a finer surface texture.

Fire Performance Ratings:

UK Fire test by Warrington Fire Research:
Class 1 to BS476 Part 7
Class 0 to BS476 Part 6

USA – Factory Mutual Standards research corp. approvals: category I, II, III, IV and V:

Category I: As an interior finish material of low fire hazard [class I building material] over non-combustible surfaces not requiring automatic sprinkler protection in and of itself.

Category II: As a protective coating to delay the ignition and reduce the surface burn rate of combustible wood and cellulosic fibre building material.

Category III: As a protective coating to delay the ignition and reduce the surface burn rate of low melting point, combustible cellular plastic building materials and to protect their dimensional stability for a brief period.

Category IV: As a protective coating for building structural steel to supplement automatic sprinkles protection in preventing structural failure temperatures of the steel in high fire hazard occupancies.

Category V: As a protective coating to the underside of a Class II insulated steel roof deck construction, to sufficiently lower the rate of fuel contribution from the Class II deck components to qualify the construction as Class I, so allowing automatic sprinkler protection to be omitted under Factory Mutuals Standards .


SonaSpray K-13 Special acoustic ceiling and wall finish can be over-painted (consult Oscar Acoustics technical department before painting as noise reverberation controlling properties can be significantly reduced if applied incorrectly), or applied with additional coats of SonaSpray. Small areas of damage can be repaired by hand.

If SonaSpray K-13 Special acoustic ceiling and wall finish is disturbed or damaged so that fibre is released into the atmosphere, the resulting contamination is harmless. Maintenance work can be undertaken while the building is occupied. Please refer to COSHH data for detailed product analysis.

SonaSpray is manufactured by ICC, Houston, Tx 
ISO 9001: 2000 certification

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