|
| Impact
and airborne sound insulation |
The impact sound value shall
be as low
as possible.
The airborne sound value shall
be as high
as possible. |
Impact and airborne sound
insulation in homes and offices
Granab systems provide effective impact and airborne sound
insulation. Effective insulation against sound from
surrounding spaces is important for a good living and working
environment. Investigations show that in older
structures, residents are often disturbed by impact sounds,
loud music, slamming doors and staircase traffic, as
well as noise from running water, lifts, ventilation and traffic.
A good sound environment has become a prioritised
requirement when building new homes, and there are also more
stringent requirements for quieter working
environments in offices and schools.
Sound classification standards stipulate acoustic
requirements for homes and other premises
The Swedish Board of Building, Planning and Housing (BBR)
has established a generally formulated requirement for acoustic
environments, calling for buildings being designed so that
residents and other occupants are effectively protected against
noise. In a general recommendation, BBR mentions sound class
C in the SIS standards SS 25267 (dwellings) and SS 25268 (other
premises), where detailed requirements and verification methods
are described. The recommendation also states that “if
better sound conditions are preferred, sound class A or B
can be selected.” In practice, dwellings are usually
planned for
sound class B to fulfil customers' wishes. The standards place
special requirements on sound insulation for low frequencies,
due to these frequencies having been found to be especially
important for the subjectively perceived sound environment.
Appendix B in SS 25267 provides guidance on how floor constructions
can be chosen so that impact sound requirements are fulfilled,
and how one can calculate which sound class will be achieved
with a certain combination of subflooring and floor construction.
In buildings with Granab's sound-dampening subfloor systems,
significantly improved sound insulation of subflooring is
achieved (even at low frequencies) in comparison with conventional,
thin floor coverings. Installations run freely under a Granab
floor do not produce structure-borne sound because they are
not attached to the framework.
Documentation of Granab systems' sound-insulating
properties
Granab systems have been developed in close collaboration
with researchers and acoustic consultants in the building
industry to satisfy highly placed demands on impact and airborne
sound insulation in homes, offices and schools. Granab systems
function as supplementary insulation for building frameworks
both in new construction and remodelling projects. The impact
and sound insulating function of the systems has been carefully
documented in accordance with the requirements of SS 25267
through, for example, lab measurements and a large number
of field measurements in completed buildings. In this way,
values for sound dampening could be established, permitting
sound insulation in buildings to be verified with calculations
as specified in SS 25267. Calculation of sound insulation
in completed buildings shall be conducted according to the
Swedish and European
standard SS-EN 12354, Parts 1 and 2 with input data from Granab.
Input data for concrete subfloors is in the BASTIAN database,
as well as at www.byggamedprefaf.se and www.betongbanken.com.
For lightweight subfloors, such as wooden subfloors, contact
Granab.
A number of examples of acoustic measurements in the SP Technical
Research Institute of Sweden's impact-sound lab, as well as
vertically between flats with Granab subfloor systems installed
on hollow-core slabs HD/F 120/19 and HD/F 120/27 in buildings. |
SS
25267
Applicable sound class limits for dwellings |
Sound class
according to
SS 25267 |
Highest permitted
impact sound level*
L´n,w+ CI,50-2500 |
Lowest permitted
airborne
sound level*
R´w+ C50-3150 |
| A |
48 dB |
61 dB |
| B |
52 dB |
57 dB |
| C |
56 dB |
53 dB |
* Verification with calculations. When performing verification
measurements, the
requirement shall be fulfilled in average values, although
deviations of no more
than 2 dB are permitted in isolated cases as long as the average
value is attained.
Accredited
sound measurements in completed building
with a Granab system on hollow-core slabs HD/F 185 mm
and HD/F 270 mm |
Examples of
measurement results |
Impact
sound
Ci, 50-2500 |
Airborne
sound
R´w+
C50-3150 |
Remarks |
Granab system, height 65 mm
incl. floor covering laid on
HD/F 270 mm |
46 dB |
65 dB |
System 3000
|
Granab system, height 70 mm
incl. floor covering laid on
HD/F 185 mm |
51 dB |
58 dB |
Granab system, height 150 mm incl. floor covering
laid on
HD/F 185 mm |
47 dB |
61 dB |
Granab system, height 165 mm incl. floor covering
laid on
HD/F 270 mm |
50 dB |
59 dB |
System 7000
|
Sound class
limits in force for residential properties in
various countries. Defined by national standards for
each
country as follows: |
| Denmark: |
DS 490 (2001). |
| England: |
Part E of Building Regulations 2000.
BIP 2023:2003.
BS 8233:1999. |
| Finland: |
SFS 5907.
Valtioneuvoston päätös No 993 1992. |
| France: |
Guide Qualitel (200). |
| Holland: |
NEN 1070 (1999).
NPR 5070:2004. |
| Iceland: |
IST 45 (2003). |
| Spain: |
Technical Building Code (TBC) and
Building Act 38/1999 (LOE). |
| Germany: |
VDI 4100 (1994).
E DIN 4109-10 (2002). |
| Austria: |
ÖNORM B 8115:2002. |
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