LOUVRES-External Weather - Scottaire

EXTERNAL WEATHER
LOUVRES
A basic weather louvre is usually mounted in the vertical
and has a row of horizontal blades shaped and positioned
so as to minimise the ingress of water. Ideal for use on the
external walls of a building at air intakes or discharges. The
free area of a conventional louvre is about 50%. However,
the blade pitch can be opened up to give up to 65% free
area but the weather keeping properties decrease
considerably and this would only be recommended where
the louvre is protected from driving rain by an adjacent
structure.
Louvres can be square or rectangular, triangular, circular, in
fact, almost any shape. They can have doors in them, be
made demountable for service access or built up into
penthouse units on screens.
There are several less conventional louvres which are
designed to:
a) be mounted in a roof pitch (angled louvre).
50mm & 70mm pitch
b) to minimise sand intake (sand trap louvre).
c) to be used in more exposed locations
(double bank chevron louvre).
d) reduce contamination between intake and discharge
where one louvre is required to handle both supply
and extract air (split louvre). 50mm & 70mm pitch
STANDARD •
LOUVRES-External Weather
38MM PITCH.
Code 0114. Square or rectangular, flanged louvre with bird
mesh for surface mounting in the vertical.
Code 0115. Square or rectangular louvre without flange
and with bird mesh for recessed mounting in the vertical.
Code 0214. Square or rectangular louvre with bird mesh
and with a reversed flange for surface mounting in the
vertical.
Code 0216. Similar to a Code 0114 but with a
50mm wide flange.
50MM PITCH.
Code 0280. Square or rectangular, flanged louvre with bird
mesh for surface mounting in the vertical.
Code 0281. Square or rectangular louvre, without flange
with bird mesh for recessed mounting in the vertical.
Code 0286. Circular flanged louvre with bird mesh for
surface mounting in the vertical.
Code 0287. Circular louvre without flange with bird mesh
for recessed mounting in the vertical.
Code 0292. Triangular flanged louvre with bird mesh for
surface mounting in the vertical.
Code 0293. Triangular louvre without flange with bird
mesh for recessed mounting in the vertical.
Code 0298. Square or rectangular penthouse louvre with
bird mesh for curb mounting.
EW1
Code 0211. Square or rectangular flanged split louvre for
surface mounting with top section for upward and lower
section for downward discharge.
Code 0208. Square or rectangular split louvre without
flange for recessed mounting with top section for upward
and lower section for downward discharge.
75MM PITCH.
Code 0282. Square or rectangular, flanged louvre with bird
mesh for surface mounting in the vertical.
Code 0283. Square or rectangular louvre, without flange
with bird mesh for recessed mounting in the vertical.
Code 0288. Circular flanged louvre with bird mesh for
surface mounting in the vertical.
Code 0289. Circular louvre without flange with bird mesh
for recessed mounting in the vertical.
Code 0294. Triangular flanged louvre with bird mesh for
surface mounting in the vertical.
Code 0295. Triangular louvre without flange with bird
mesh for recessed mounting in the vertical.
Code 0609. Square or rectangular penthouse louvre with
bird mesh for curb mounting.
Code 0209. Square or rectangular flanged split louvre for
surface mounting with top section for upward and lower
section for downward discharge.
Code 0213. Square or rectangular split louvre without
flange for recessed mounting with top section for upward
and lower section for downward discharge.

STANDARD • con’t
100MM PITCH.
Code 0284. Square or rectangular, flanged louvre with bird
mesh for surface mounting in the vertical.
Code 0285. Square or rectangular louvre, without flange
with bird mesh for recessed mounting in the vertical.
Code 0290. Circular flanged louvre with bird mesh for
surface mounting in the vertical.
Code 0291. Circular louvre without flange with bird mesh
for recessed mounting in the vertical.
Code 0296. Triangular flanged louvre with bird mesh for
surface mounting in the vertical.
Code 0297. Triangular louvre without flange with bird
mesh for recessed mounting in the vertical.
Code 0610. Square or rectangular penthouse louvre with
SIZES
38MM PITCH.
Any nominal length or height up to 1500mm provided
the other dimension does not exceed 1200mm.
50MM PITCH.
Any nominal length or height in one piece, provided
the face area does not exceed 4 sq metres. However,
any nominal length or height can be made up from
sections bolted together and, where necessary,
supported on a metal framework. The maximum
diameter for a circular louvre is 2000mm in one
section. A larger diameter can be manufactured in
multiple sections and bolted together.
75MM PITCH.
Any nominal length or height in one piece, provided
the face area does not exceed 4 sq metres. However,
any nominal length or height can be made up from
sections bolted together and, where necessary,
supported on a metal framework. The maximum
diameter for a circular louvre is 2000mm in one
section. A larger diameter can be manufactured in
multiple sections and bolted together.
100MM PITCH.
Any nominal length or height in one piece provided
the face area does not exceed 4 sq metres. However,
any nominal length or height can be made up from
sections bolted together and, where necessary,
supported on a metal framework. The maximum
diameter for a circular louvre is 2000mm in one
section. A larger diameter can be manufactured in
multiple sections and bolted together.
LOUVRES-External Weather
bird mesh for curb mounting.
STANDARD SPECIFICATION
Sandtrap.
Code 0680. Square or rectangular sandtrap louvre flanged
for surface mounting.
Code 0681. Square or rectangular sandtrap louvre without
flange for recessed mounting.
Angled
Code 0682. Square or rectangular flanged louvre with bird
mesh for surface mounting in a angled roof up to 40
degrees from the vertical.
Code 0683. Square or rectangular louvre without flange
with bird mesh for recessed mounting in an angled roof up
to 40 degrees from the vertical.
SANDTRAP
Any nominal length or height in one piece provided
the face area does not exceed 4 sq metres. Larger sizes
can be made up but they become very heavy to handle.
Please contact the factory for details.
ANGLED
Any nominal length or height in one piece provided
the face area does not exceed 4 sq metres. Larger sizes
can be made up but they become very heavy to handle.
Please contact Head Office for details.
CONSTRUCTION
Manufactured from aluminium extrusions with mitred
corners The 38mm pitch louvres have cleated corners.
All others have welded corners.
The bird mesh is manufactured from steel wire with
welded joints and 25mm cells.
FINISHES
Louvres are mill finish aluminium. The bird mesh is
galvanised after manufacture.
FIXINGS
Surface mounted louvres are fixed through the face
flange. Screw holes are not provided as the centres
required vary considerably. Fixing type 0F2. Recessed
louvres are fixed through the stack. Screw holes are not
provided. Fixing Type 0F2.
PACKAGING
Louvres are packed in polythene and then
sandwiched between two pieces of hard board and
banded with protective cardboard corners and sides.
TECHNICAL INFORMATION
See pages 8 - 10
EW2

FINISHES
Any BS, RAL or NCS colour. 38 mm pitch, Code
0145. Other pitches, Code 0146. please specify the
colour reference.
Satin anodised. Code 0147 satin. It may be possible to
anodise to other colours and finishes depending on
quantity. Please contact the Head Office for details.
FIXINGS
The flanges can be pre-drilled. Please provide details of
fixing centres and whether or not countersinking is
required. Fixing type OF1. Fixing tabs can be provided
to the rear of the stack to fix to brick or steel work.
Please provide details of your requirements. Fixing
type OF 11.
DRIP SILLS
A drip sill can be provided, in the same finish as the
louvre. Details of the codes and dimensions are given
below.
Drip Sill
to suit
Flanged
External
Weather
Louvre
50mm
45°
Code 0605 38mm Pitch
Code 0606 50mm Pitch
Code 0607 75mm Pitch
Code 0608 100mm Pitch
LOUVRES-External Weather
2
10
Drip Sill
to suit
Recessed
External
Weather
Louvre
50mm
OPTIONAL ALTERNATIVES/ADDITIONS
45°
Code 0601 38mm Pitch
Code 0602 50mm Pitch
Code 0603 75mm Pitch
Code 0604 100mm Pitch
D = Nominal Duct size
Model shown is Code 0114, 38mm pitch
Small External Weather Louvre with Bird Mesh
If no Bird Mesh is fitted, Code becomes 0112
2
EW3
10
SUPPORTING FRAMEWORK
The necessary supporting framework in steel or
aluminium can be supplied to support multiple
sections, where necessary, or to provide a louvred
screen. Please provide details.
DOORS
Single or double doors can be provided in all louvres
and penthouses except for the 38mm pitch range.
The doors are hinged and fitted with Eurolocks.
Code 0279. Please provide details.
DE-MOUNTABLE PANELS, HINGED OR
CUTAWAY SECTIONS
These can be provided to your requirements. Please
provide details. The louvre product Code prefix
becomes 9 instead of 0.
ORDERING DETAILS
• The code for the basic grille should have 13 digits.
See page 1.
• Please always give length first, then height.
• Add codes for additions/alternatives as suffixes.
EXAMPLE:
Example. A 50mm pitch flanged triangular louvre
with a nominal base dimension of 1500mm and a
nominal base to apex height of 1000mm with a
hinged access door in it for surface mounting with
pre-drilled fixing holes would be coded:-
0292/01500/1000+0279+0F1.
Applications. Supply * Extract * Sidewall *
26.2
35
2.5
D + 52.4mm D - 5mm D
37.5Typ.
37.5
2.5

D - 5mm
D = Nominal Duct size
Model shown is Code 0115
Recessed Frame Small External Weather Louvre with Bird Mesh
If no Bird Mesh is fitted, Code becomes 0113
D
D - 5mm
37.5Typ.
37.5
37.5Typ.
37.5
39
37
D = Nominal Duct size
Model shown is Code 0211
50mm Reversed Flange External Weather Louvre with Bird Mesh
If no Bird Mesh is fitted, Code becomes 0210
5.0
50
2.5
2.5
D
D + 92.6mm
LOUVRES-External Weather
38mm PITCH (STANDARD)
D - 5mm
D
38mm PITCH (50mm FLANGE)
37.5Typ.
37.5
D = Nominal Duct size
Model shown is Code 0214
Reversed Flange External Weather Louvre with Bird Mesh
If no Bird Mesh is fitted, Code becomes 0212
50
37
D = Nominal Duct dize
Model dhown is Code 0216
50mm Flanged Small External Weather Louvre with Bird Mesh
If no Bird Mesh is fitted, Code becomes 0215
EW4
2.5
D + 92.6mm D - 5mm D
37.5Typ.
37.5
37
5.0
2
30
D + 51mm
2.5

50
D + 84mm
50 Pitch
3
50
Code 0280 Flanged Frame
for surface mounting
50mm pitch
D + 84mm
LOUVRES-External Weather
100 Pitch
5
50mm PITCH
D
Nominal
Duct
Size
Code 0284 Flanged Frame
for surface mounting
100mm pitch
3
50 Pitch
100
50
Code 0281 Recessed Frame Code 0282 Flanged Frame
for surface mounting
75mm pitch
5
3
D
Nominal
Duct
Size
D
Nominal
Duct
Size
EW5
D + 84mm
75 Pitch
100mm PITCH
3
75
100 Pitch
75mm PITCH
5
D
Nominal
Duct
Size
100
75 Pitch
Code 0285 Recessed Frame
75
Code 0283 Recessed Frame
5
D
Nominal
Duct
Size
3
D
Nominal
Duct
Size

A B
Penthouse Louvre c/w Mitre Corners
Code 0298 50mm Pitch
Code 0609 75mm Pitch
Code 0610 100mm Pitch
Other roof styles available upon request
Code 0286 50mm Pitch surface mount
Code 0287 50mm Pitch recessed
Code 0288 75mm Pitch surface mount
Code 0289 75mm Pitch recessed
Code 0290 100mm Pitch surface mount
Code 0291 100mm Pitch recessed
LOUVRES-External Weather
Model shown is Code 0279
Door available in 50, 75 &100mm pitch
Various door furniture can be fitted
EW6
Height H
Standard Flange = 50mm
C/W
Birdmesh
25mm Clearance
Overall size A x B = Overcurb + 50mm
Code 0292 50mm Pitch surface mount
Code 0293 50mm Pitch recessed
Code 0294 75mm Pitch surface mount
Code 0295 75mm Pitch recessed
Code 0296 100mm Pitch surface mount
Code 0297 100mm Pitch recessed

100
100
5
5
50
50
LOUVRES-External Weather
100
100
Nominal Width
Stack Width = Nominal - 10mm
50
Sand Trap Louvre Code 0636 with Flanged Frame
100 x 25 Channel
Mansard Type Angled Weather Louvre Code 0638 with Flanged Frame
Nominal Width
Stack Width = Nominal - 10mm
50
100 x 25 Channel
EW7
100
50
25
100
50
60°
5
Bird Guard
Stack Height = Nominal - 10mm
Nominal Height
5
Stack Height = Nominal - 10mm
Nominal Height

100
100
5
5
100
100
Nominal Width
Stack Width = Nominal - 10mm
LOUVRES-External Weather
Mansard Type Angled Weather Louvre Code 0639 with Recessed Frame
Nominal Width
Stack Width = Nominal - 10mm
50
50
Sand Trap Louvre Code 0637 with Recessed Frame
100 x 25 Channel
100 x 25 Channel
EW8
100
25
100
60°
Note: Particular care needs to
be taken with sealing this type of
louvre to the building structure.
5
Bird Guard
Stack Height = Nominal - 10mm
Nominal Height
5
Stack Height = Nominal - 10mm
Nominal Height

LOUVRES-External Weather
EXTERNAL WEATHER LOUVRES
PERFORMANCE DATA 38mm PITCH
•
We would recommend that, on air intake, the duct
velocity does not exceed 1.5m/s (3.0m/s core velocity)
at the louvre in order to minimise the ingress of water.
This can be increased to 2.0m/s (4.0m/s core velocity)
on extract applications provided the noise and pressure
drop criteria are met. Example. to select a louvre for
air intake handling 0.3m3 /s, place a rule on this point
PERFORMANCE DATA
EW9
on the volume line and ensure that it crosses the duct
velocity line @ 1.5m/s. Note where the rule the pivot
line and then rotate the rule about this point to obtain
a suitable combination of length and height. In this
case a 450mm x 450mm. Read off the pressure drop
and N.R., adding 10% to the pressure drop if
birdmesh is fitted.
For core velocity, multiply duct velocity by 2 (i.e. 50% free area). Data based on intake air, for exhaust
air add 20% to pressure drop and add 5 NR. For inclusion of Birdmesh add 10% to the pressure drop.
Volume (Q)
m 3 /s
2.0
1.5
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.15
0.1
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
60
50
40
30
20
Pressure
drop ∆(Pt)
Pa
NRLW
50
20
5
3
Duct
Velocity
m/s
4.0
3.0
2.0
1.0
0.5
200
250
300
350
400
450
500
600
700
800
900
1000
1100
1200
1300
1400
1500
Nominal Louvre Size
Width mm x Height mm
0.04
0.05
0.06
0.07
0.08
0.09
0.1
0.15
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.5
2
Pivot line
Nominal Duct Area 2 m
200
250
300
350
400
450
500
600
700
800
900
1000
1100
1200
1300
1400
1500

LOUVRES-External Weather
EXTERNAL WEATHER LOUVRES
PERFORMANCE DATA 50mm PITCH
•
We would recommend that, on air intake, the duct
velocity does not exceed 1.5m/s (3.0m/s core velocity)
at the louvre in order to minimise the ingress of water.
This can be increased to 2.0m/s (4.0m/s core velocity)
on extract applications provided the noise and pressure
drop criteria are met. Example. To select a louvre for
air intake handling 0.3m3 /s, place a rule on this point
on the volume line and ensure that it crosses the duct
velocity line at 1.5m/s. Note where the rule crosses the
pivot line and then rotate the rule about this point to
obtain a suitable combination of length and height.
PERFORMANCE DATA
EW10
In this case a 450mm x 450mm. Read off the pressure
drop and N.R., adding 10% to the pressure drop if
birdmesh is fitted. To calculate the size of a louvre to
handle more than 2.0m 3 /s divide the volume by a
number that gives a volume equal to less than 2m/s
and use the Nomogram. It is reasonably safe to read
the pressure drop and NR from the nomogram and
use it for the larger louvre. Remember to multiply the
resulting duct area shown on the pivot line by the
same number used to divide the volume. This will give
the face area of the required louvre.
For core velocity, multiply duct velocity by 2 (i.e. 50% free area). Data based on intake air,
for exhaust air add 20% to pressure drop and add 5 NR. Graph includes the fitting of birdmesh.
Volume (Q)
m 3 /s
2.0
1.5
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.15
0.1
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
Code 280 / 281 Nominal Louvre Size
Width mm x Height mm
60
50
40
30
Pressure
drop ∆(Pt)
Pa
NRLW
30
20
10
5
Duct
Velocity
m/s
4.0
3.0
2.0
1.0
0.5
200
250
300
350
400
450
500
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000
0.04
0.05
0.06
0.07
0.08
0.09
0.1
0.15
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.5
2
3
4
Pivot line
Nominal Duct Area 2 m
200
250
300
350
400
450
500
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000

LOUVRES-External Weather
EXTERNAL WEATHER LOUVRES
PERFORMANCE DATA 75mm PITCH
•
We would recommend that, on air intake, the duct
velocity does not exceed 1.5m/s (3.0m/s core velocity)
at the louver in order to minimise the ingress of water.
This can be increased to 2.0m/s (4.0m/s core velocity)
on extract applications provided the noise and pressure
drop criteria are met. Example. To select a louvre for
air intake handling 0.3m3 /s, place a rule on this point
on the volume line and ensure that it crosses the duct
velocity line at 1.5m/s. Note where the rule crosses the
pivot line and then rotate the rule about this point to
obtain a suitable combination of length and height.
PERFORMANCE DATA
EW11
In this case a 450mm x 450mm. Read off the pressure
drop and N.R., adding 10% to the pressure drop if
birdmesh is fitted. To calculate the size of a louvre to
handle more than 2.0m 3 /s divide the volume by a
number that gives a volume equal to less than 2m/s
and use the Nomogram. It is reasonably safe to read
the pressure drop and NR from the nomogram and
use it for the larger louvre. Remember to multiply the
resulting duct area shown on the pivot line by the
same number used to divide the volume. This will give
the face area of the required louvre.
For core velocity, multiply duct velocity by 2 (i.e. 50% free area). Data based on intake air,
for exhaust air add 20% to pressure drop and add 5 NR. Graph includes the fitting of birdmesh.
Volume (Q)
m 3 /s
2.0
1.5
1.0
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.15
0.1
0.09
0.08
0.07
0.06
0.05
0.04
0.03
0.02
Code 282 / 283 Nominal Louvre Size
Width mm x Height mm
60
50
40
30
20
Pressure
drop ∆(Pt)
Pa
NRLW
40
30
20
10
5
Duct
Velocity
m/s
4.0
3.0
2.0
1.0
0.5
200
250
300
350
400
450
500
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000
0.04
0.05
0.06
0.07
0.08
0.09
0.1
0.15
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1.0
1.5
2
3
4
Pivot line
Nominal Duct Area 2 m
200
250
300
350
400
450
500
600
700
800
900
1000
1100
1200
1300
1400
1500
1600
1700
1800
1900
2000