1
24
25
ØD
Ød
ØU*
OLC Size (Ød)
ØD
[mm]
*ØU
m
[kg]
100 200 108-110 0,8
125 250 133-135 1,0
160 300 168-170 1,2
OLC Size
*D
n,e,w
Ød [l/s] [m3/h] [l/s] [m3/h] [l/s] [m3/h] [dB]
100 19 68 24 86 27 97 49
125 28 101 34 122 39 140 47
160 40 144 49 176 56 202 44
p
t
= 10 [Pa]
p
t
= 15 [Pa]
p
t
= 20 [Pa]
lindab | we simplify construction
Overflow unit OLC
Lindab reserves the right to make changes without prior notice
2021-03-11
Description
OLC is a circular overflow unit for installation directly into a
wall. OLC consists of two sound-attenuating baffles, which
are mounted on both sides of the wall.
• Discrete design
• Sound-attenuating baffles
Maintenance
The sound attenuation baffles on both sides of the wall can
be removed to enable cleaning of internal parts. The visible
parts of the unit can be wiped with a damp cloth.
Materials and finish
Installation bracket: Galvanised steel
Front plate: Galvanised steel
Standard finish: Powder-coated
Standard colour: RAL 9010 or 9003, Gloss 30
The OLC is available in other colours. Please contact Lindab’s
sales department for further information.
Dimensions
Quick selection
Order code
Product OLC aaa
Type
OLC
Size
100, 125, 160 mm
Example: OLC - 125
*ØU = Cutout dimension in wall = Ød + 10 mm
* Values valid for cavity wall with 95 mm insulation.
OLC Size (Ød)
ØD
[mm]
*ØU
m
[kg]
100 200 108-110 0.8
125 250 133-135 1.0
160 300 168-170 1.2
2
lindab | we simplify construction
Overflow unit OLC
Lindab reserves the right to make changes without prior notice
2021-03-11
Lindab reserves the right to make changes without prior notice
2021-03-11
Accessories
OLCZ - Perforated wall sleeve
OLC installed in wall
OLC with OLCZ installed in wall
OLCZ optional accessory.
For further information, see OLC installation instruction.
Order code
Product OLCZ aaa
Type
OLCZ
Size
Ø100, 125, 160 mm
Example: OLCZ - 160
3
100 125 160
50
45
40
35
30
25
20
15 20 30 40 50 70 100 150 200
60 70 100 200 300 500 700
qV[l/s]
qV[m3/h]
5
7
10
15
20
30
50
70
100
∆pt [Pa] OLC
LWA dB(A)
Size
[mm] 125 250 500 1K 2K *D
n,e,w
100 32 46 46 48 54 49
125 34 43 43 46 51 47
160 34 40 40 44 50 44
Size
[mm] 125 250 500 1K 2K
*Dn,e,w
100 30 40 38 42 50 43
125 30 37 37 42 49 43
160 30 34 34 40 50 41
Size
[mm] 125 250 500 1K 2K
*Dn,e,w
100 24 24 23 32 40 31
125 23 24 23 33 40 31
160 24 24 23 32 39 30
Centre frequency [Hz]
Centre frequency [Hz]
Centre frequency [Hz]
lindab | we simplify construction
Overflow unit OLC
Lindab reserves the right to make changes without prior notice
2021-03-11
Technical data
Capacity
Air flow rate qv [l/s] and [m3/h], total pressure loss Δpt [Pa] and
sound power level LWA [dB(A)] are specified for a OLC unit on
both sides of the wall.
Dimensioning diagram
Element-normalised reduction figure Dn,e
Weighted value (Dn,e,w) evaluated according to ISO 717-1
Cavity wall with 95 mm insulation
Cavity wall with 70 mm insulation
Solid wall without insulation
44
20
15
10
5
0
0
5
10
15
20
25
0
5101520253035404
55
0
Area of wall [m²] / Number of units [-]
Difference between wall and unit ( Rw - Dn, e, w ) [dB]
Reduction of wall (Rw) [dB]
Area [m2]10 2 1
Correction [dB] 0-
7-
10
lindab | we simplify construction
Overflow unit OLC
Lindab reserves the right to make changes without prior notice
2021-03-11
Lindab reserves the right to make changes without prior notice
2021-03-11
Technical data
Sample calculation
When dimensioning an overflow diffuser, calculate the decrease
in the wall’s noise-reducing properties.
For these calculations, the area of the wall and sound reduc-
tion figure R must be known.
This is adjusted in relation to the unit’s Dn,e value. Dn,e is the
unit’s R value given at a transmission area of 10 m2, as speci-
fied in ISO 140-10.
The Dn,e value can be converted into the R value for other
transmission areas using the table below.
The diagram below indicates the decrease of the sound reduc-
tion index of the wall, for a given octave band value (Dn,e ) or
weighted value ( Dn,e,w ).
As a rough estimate the calculation can be performed directly
using the wall´s Rw value and the weighted elementnormalized
level difference Dn,e,w of the unit.
Example:
(See diagram below) :
Rw (wall): 50 dB
Dn,e,w (diffuser): 44 dB Rw- Dn,e,w = 6 dB
Area of wall: 20 m2
Number of Units: 1 20 m2/1 = 20 m2
Indicated reduction of Rw (wall): 5 dB
Rw value for wall with unit: ~50-5 = 45 dB
The calculation can also be performed using the following for-
mula:
where:
- Rres is the resulting reduction figure for wall and diffuser.
- S is wall area.
- Dn,e is the unit’s Dn,e value.
- Rwall is the wall’s R value without unit.
+
=
)
10
-0,1 · Rwall
(Swall
)10-0,1·Dn,e
(10m²
Swall
Log10Rres
-
1
-
2
-
3
-
4
