Carnes PFAB User Manual

Non-Drainable Blade LouversLouvered Penthouses

Louvered Penthouses

F-70 www.carnes.com

Galvanized Steel Penthouse
High Performance

Model: PFAB Post Corner

Standard Curb Cap

Installation

Roof
Curb

Curb Cap

Special
Curb Cap
Dimension

2-3/4”
(std.)

Post Corner

Independent louver panels
(sides) are built and
mounted to the internal
frame with corner covers
installed.

Curb Cap I.D.

(Throat Dim. + 4-1/2”, std.)

3”

2”

C

Water Diverter

Pitched Roof
Option Shown

1-1/2”
Internal Support
Structure

Screen

Internal Sill/Water Catch

Throat Dimension

A x B

Model PFAB

t Standard Specifications

Frame: 18 gauge galvanized steel, 4” deep
Blades: J style, 20 gauge galvanized steel, positioned at 45°

angles on approximately 4” centers.
Roof: Fabricated at .050” (1.3mm) thickness 20 gauge formed
galvanized steel, roof is secured with sheet metal screws for
ease in removal. Flat roofs are cross-broken for adequate
element run-off. Models with pitched roofs have a 1” in 12” or 3”
in 12” (25.4mm in 305mm or 76mm in 305mm) pitch.
Internal Framing: 1-1/2” x 1-1/2” x 1/8 (38mm x 38mm)
framing angles of 20 gauge galvanized steel on 48” (1219mm)
maximum centers.
Finish: galvanized steel mill finish for low maintenance and
resistance to corrosion

Screen: 3/4” x .051” flattened aluminum birdscreen
Sizing: Order size is actual throat dimensions. Throat is under-

cut 1/2” (12mm) in both “A” and “B” dimensions for installation
allowance.

Minimum: 12”w x 12”l x 12”h (305mm x 305mm x 305mm)
Maximum: 72”w x 220”l x 80”h (1829mm x 5588mm x 2032mm).

Unlimited size with multiple section assembly.

Note: Louvered Penthouses are reasonably weather tight.
However, they are not recommended for use where airborne
water droplets from storms or high winds may damage the
interior of the building. Provisions should always be made for
potential wind driven rain or snow carry over because air can
pass completely through a Louvered Penthouse.

Non-Drainable Blade Louvers

Louvered Penthouses

Louvered Penthouses

www.carnes.com F-71

Model PFAB

Free Area in Square Feet

HEIGHT WIDTH IN INCHES
INCHES

8 12 18 24 30 36 42 48 54 60

10 0.07 0.11 0.19 0.26 0.34 0.41 0.49 0.56 0.64 0.71
12 0.13 0.23 0.38 0.53 0.68 0.83 0.98 1.13 1.28 1.43
18 0.23 0.41 0.67 0.93 1.20 1.46 1.73 1.99 2.25 2.52
24 0.38 0.67 1.10 1.54 1.97 2.40 2.84 3.27 3.70 4.14
30 0.48 0.84 1.39 1.94 2.49 3.04 3.58 4.13 4.68 5.23
36 0.63 1.11 1.82 2.54 3.25 3.98 4.59 5.41 6.13 6.85
42 0.73 1.28 2.11 2.95 3.78 4.61 5.44 6.27 7.11 7.94
48 0.88 1.54 2.56 3.56 4.55 5.55 6.56 7.56 8.58 9.56
54 0.98 1.72 2.84 3.95 5.07 6.18 7.30 8.42 9.53 10.65
60 1.12 1.98 3.27 4.56 5.84 7.12 8.41 9.70 10.98 12.27
66 1.22 2.16 3.56 4.96 6.38 7.76 9.16 10.56 11.96 13.36
72 1.37 2.42 3.99 5.58 7.13 8.70 10.27 11.84 13.41 14.98
78 1.47 2.60 4.28 5.96 7.65 9.33 11.02 12.70 14.38 16.07
84 1.62 2.86 4.71 6.57 8.42 10.27 12.13 13.98 15.83 17.69
90 1.72 3.03 5.00 6.97 8.94 10.91 12.87 14.84 16.81 18.78
96 1.87 3.30 5.43 7.57 9.71 11.85 13.98 16.12 18.26 20.40

PFAB Selection and Examples

Example 1:

Airflow given as 12,000 cfm – select four louver sides

A. 12,000 cfm ÷ 4 louver sides = 3,000 cfm per side

B. 3,000 cfm ÷ 840 fpm = 3.57 ft² (F.A.) per side

C. Select louver from the above free area chart

42”w x 30”h = 3.58 ft² (F.A.)

3.58 ft² x 4 sides = 14.32 ft² total

Example 2:

To select “rectangular” shape in lieu of square

A. Simply break down 14.32 ft²

4 + 4 + 3 + 3 = 14 ft²

B. Select louver from above free area chart

3 ft² = 36” x 30”
4 ft² = 46” x 30”

Penthouse size 46”w x 36”l x 30”h