TECHNICAL DATA SHEET
Sto Acoustic Spray Plaster
Mineral sound absorbing spray applied plaster.
Material description • High degree of reflectivity and Application
• Medium to rough surface The substrate should be solid, dry,
structure. Structure may vary load-bearing and free from grease
according to method of or other adhesion reducing
• Low weight when dry.
• Fire behaviour: Even slightly uneven surfaces
non-combustible. should be levelled before applying
Sto Acoustic Spray Plaster, as the
material will follow the exact lines
Uses of the substrate without smoothing
Type of material Uses
Sound absorbing, single For use in rooms where the clarity Strongly absorbent substrates such
component spray plaster; improved of speech needs to be improved by as gypsum plasterboard should be
mineral binder basis, hydraulically regulating the sound reverberation primed with undiluted StoSilent
drying. time. Prim. In the case of gypsum
plasterboard substrates, observe
Apply in multiple layers to achieve Particularly suitable for application the reduced support beam spacing
a plaster thickness of 15 mm. to large areas such as in admini- of 30 cm.
stration buildings, government
Composition buildings, schools, universities, Smooth substrates and gypsum
Portland cement, vinylacetate- swimming pools (not salt water), plasterboard should be sprayed
ethylene copolymer, fillers, factories or churches etc. where with StoSilent Quartz (art. no.
additives. the sound absorption requirement 0894-001) to improve adhesion.
is not necessarily that high. Allow sufficient drying time.
Product characteristics For use on ceilings and walls not Material application
subject to mechanical abrasion. For each batch of material, mix an
entire sack of the product with
• Good sound absorption qualities
Areas of use 20 - 22 l water and mix slowly for
in mid- and high-frequency
For interior use ca. 6 minutes in a positive mixer
until lump-free. The amount of
• Applicable with a spray pistol Restrictions water to be added depends on the
(Trichterpistole) or spiral pump Uses not clearly described in this planned method of application
with variable settings and fine Technical Data Sheet should only (spray pistol or spiral pump). For
spray set. Sound absorption take place after consultation with spiral pumps, the lower amount of
qualities vary according to the Sto AG. water is generally sufficient.
method of application.
• Anti-condensatory properties as
The material should be sprayed in
a result of high water absorption
several coats until it reaches a
thickness of 15 mm.
TDS 0782/INT.EN Sto Acoustic Spray Plaster 04/01.2006 2/5
A minimum of 5 coats will be Drying / hardening double crosswise (e.g. horizontal
necessary for this. Between Dries hydraulically. then vertical) spraying at low
individual coats, allow to dry for pressure with StoSilent Color.
24 hours. The material must in Consumption
places be sprayed open-pore. Do Approx. 15 l dry mass for 15 mm
not allow the material to run! coating thickness measured at the Storage and transport
Material that has run is a visible highest point.
application flaw. The acoustic Marking
effect is not given for material that Application temperature In accordance with European
has run. Air and substrate temperature Union guidelines and national
should not be less than + 5 °C, regulations:
Spraying with a spray pistol relative humidity below 70 %.
(Trichterpistole): (until the material has completely VbF: -
We recommend use of a set.) EU/GefStoffV: Xi - irritant
compressor with a suction of at GGVS/ADR: -
least 350 l/min and pressure of Note: UN-Nr.: -
4 bars. Standard nozzle diameter In very warm and dry conditions,
8mm or 6mm, to achieve a finer moisten already applied layers of GISBAU-Code: ZP01
spraying structure. Spraying plaster before applying the next in VVS-Code: 1610
pressure should be ca. 2.5 - 3.0 order to avoid 'burning' of the BAGT-Nr.: 617300
bars. Spraying distance: at least plaster.
50 cm. Whilst spraying, move Storage
continually with a circular motion: Cleaning of tools and machinery Store in dry conditions.
do not spray on a single point. Immediately after use with water.
The material must not form a Storage life
sealed layer. Renovation In unopened sacks, product can
Using an Industrial vacuum be stored for a minimum of
Spraying with a spiral pump cleaner with brush fitting, remove 9 months. (Relevant data: refer to
(Schneckenpumpe): built-up dust from the surface. packaging).
Spiral pumps with variable settings Finally, spray StoSilent Color
should be used, e.g. PFT N2V or crosswise 1 - 2 times at low
Strobl 203, or Strobl 326. Where pressure. Environment and health
possible, use a half-output
stator/rotor. Suction should be at Risk warnings (R-phrases)
least 400 l/min, output pressure at Supply R38: Irritating to skin.
least 4 bars. Max. hose length R41: Risk of serious damage to
10 m with a hose diameter of Product code and name eyes.
25 mm. Fine plaster fitting for 00782 Sto Acoustic Spray Plaster
decorative plaster; nozzle size Safety precautions (S-phrases)
10mm. Spraying distance Packaging S24: Avoid contact with the
50 - 70mm. Move continually Sack, 50 l (approx. 10 kg) skin.
while spraying. Material must not S26: In case of contact with
be allowed to form a sealed layer. Colours eyes, rinse immediately
Natural white. with plenty of water and
Note: seek medical advice.
In cases of large connected wall Colour design is possible with S36/37/39: Wear suitable
surfaces, it is not recommended to StoSilent Color (art. 00637-001). protective clothing, gloves
spray from the scaffolding itself, The last two spray coatings of and eye/face protection.
but rather from a mobile platform plaster should be pre-tinted for this S51: Use only in well ventilated
lift. This avoids leaving the purpose with the addition of max. areas.
'shadow' of the scaffold on the 0,2 l full tint pigment or StoTint
surface, and the correct spraying Aqua to the water used to prepare Measures in case of accident
distance can be maintained Sto Acoustic Spray Plaster. Clean up material and dispose of
throughout the spraying procedure. Equalisation to the exact tint according to local regulations.
should then take place through a
TDS 0782/INT.EN Sto Acoustic Spray Plaster 04/01.2006 3/5
Table 1: Physical data
Tested to Value/Test result Unit
in supplied form [kg/dm³]
wet material 6,70 [kg/m²]
dry material 2,50 [kg/m²]
11,0 – 13,5 
Fire protection class DIN 4102 A2
71 * [%]
61 * [%]
With the indication of the characteristic values it concerns average values. Due to the use of natural raw materials in our products the actual value can
deviate slightly, without impairment of the product suitability.
* Dependent on spraying structure.
Sto Acoustic Spray Plaster Sound Absorption Values
Plaster Thickness: 15 mm Test Area: 11,72 m²
Volume of Echo Chamber: 171.19 m³ Test Sound: Terz
Reception Filter: Terz
Sound Absorption Values of Sto Acoustic Spray Plaster
Sound Absorption Value
0 1000 2000 3000 4000
TDS 0782/INT.EN Sto Acoustic Spray Plaster 04/01.2006 4/5
Sto Acoustic Spray Plaster
Pos. m² Description Price Total
per m² price
Masking off and protection of floors, walls and other areas.
2 Scaffold / Access
Scaffolding or access towers must be so arranged that spraying is carried
out at a range of 70 cm from the ceiling or wall, so that an even surface
structure can be achieved.
Scaffold access required for other works such as levelling the substrate,
fixing Sto Acoustic Starter Track, spray application of StoSilent Quartz etc.
3 Substrate testing and treatment
Test the substrate for dryness and load-bearing qualities. All adhesion
reducing substances must be removed. Irregularities in the substrate must
be levelled and left to dry.
Prime strongly absorbent substrates with StoSilent Prim (Art. No. 0880-
001). StoSilent Prim must not be allowed to form a shiny film on the
4 Preparation for Spray Plaster
Smooth substrates such as fair faced concrete, gypsum boards, smooth
plaster etc. must be spray coated with the bonding bridge StoSilent Quartz
(Article Nr. 00894-001) and left to dry for 1-2 days.
Rough substrates do not need to be primed.
Cement or lime bound substrates should be lightly pre-wetted.
5 Application of Sto Acoustic Spray Plaster
Mix Sto Acoustic Spray Plaster (50 l sack), (Art. No. 00782-002) (white)
with approx. 20 - 22 litres water in a forced action mixer and spray apply
using a Sto Spray Gun in 5 coats, each coat separated by 24 hrs. (Only mix
Plaster thickness 15 mm
Spray Structure: fine or coarse
Additional steps (if necessary)
6 Levelling plaster
Levelling uneven areas with lime-cement plaster
Up to 5mm...................................................
Up to 10mm.................................................
7 Colour design
Sto Acoustic Spray Plaster mixed with water tinted with up to 0,2 litres
Once dried, Sto Acoustic Spray Plaster over-sprayed with StoSilent Color
(Art. No. 00637-001)
TDS 0782/INT.EN Sto Acoustic Spray Plaster 04/01.2006 5/5
Disposal Certificates and test reports General information
Waste has to disposed considering
the local, official regulations. General approval for use as a For all contracts - whether made
Material into drains to arrive do construction material in Germany: verbally or in writing - Sto AG
not leave. general conditions of sale apply.
• Report P-BWU03-I-16.4.39,
Waste key in accordance with the Validity
European Waste Catalog: This Technical Data Sheet is valid
MPA - Materialprüfungsanstalt
17 09 03. outside Germany, in all countries
without Sto subsidiary.
For further information on
handling, storage and disposal of Sto AG
Determination of sound
the product, please refer to the Ehrenbachstrasse 1
absorption: Sto Acoustic Spray
current EU material Safety Data D-79780 Stühlingen
Plaster on gypsum plasterboard:
Sheet, available für professional Germany
users. (Relevant data). • Report Phone: +49 7744 57-1131
Müller-BBM in Planegg, Fax: +49 7744 57-2131
Physical data E-Mail: email@example.com
Determination of sound
Physical data absorption: Sto Acoustic Spray Internet: www.sto.com
See table 1. Plaster on wood particle board.
Müller-BBM in Planegg,
Test reports o.ae. on request.
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03-872 Warszawa 08302 Mataró 582 77 Linköping 8172 Niederglatt Paisley PA3 3BQ
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Shanghai Sto Ltd. Sto SEA Sdn. Bhd. Sto SEA Pte Ltd Sto Corp.
Shanghai 200001 47100 Puchong, Selangor Singapore 575625 Atlanta, Georgia 30336-5609