CorroMax 21™

About CorroMax 21™

A reliable product that stands the test of time, Fielders® CorroMax 21™ can be used in either roofing or walling applications. This profile is both popular and versatile, while being able to reflect either a modern or traditional design depending on the application. Complemented by Fielders® range of heritage products, beautiful authentic restorations can also be achieved. Available in 0.40mm and 0.48 base metal thicknesses.

CorroMax™ 21 offers the benefits of strength, aesthetic appeal and a tougher roof, so it’s easy to see why CorroMax™ 21 is the ideal roofing product for home owners, renovators, designers and builders alike.
Compared to Fielders traditional S-Rib corrugated profile, the ribs of CorroMax™ 21 are 30% deeper, allowing for a higher rainwater carrying capacity and making it suitable for roof pitch designs down to 3 degrees.

CorroMax 21™ NON-CYCLONIC Profile

Material Specifications

PropertyNotes
Base Metal Thickness (mm)0.400.48BMT
Total Coated Thickness (mm)0.47*0.53*TCT
Mass / Unit LengthCOLORBOND®3.404.00kg/m
Mass / Unit AreaCOLORBOND®4.405.92kg/m2
Minimum Yield StrengthG550G550Base Steel Designation
Coating ClassZ600 (Heritage Galvanised)
AM100 (COLORBOND®)
AM125 (Zincalume)
AM150 (COLORBOND® Ultra)
Z450 (Galvanised)
Minimum Coating g/m2 of Zinc -
Aluminium
Coverage (mm)762
ToleranceLength: +10mm, -10mm, Width: +4mm, -4mm
Table CM21 MS NC 001 - CorroMax 21™ Non-Cyclonic
Notes:
  1. CorroMax 21™ is manufactured in accordance to AS 1445 and from materials in accordance to AS 1397 and AS 2728. It is to be installed in accordance with AS 1562 and HB 39.
  2. The sectional properties are theoretical values per sheet width. These properties are gross values only.
  3. *is based on Standard COLORBOND® single-sided material. For other painted steel options please contact a Fielders® representative.

Rainfall Capacity

For further information, please refer to sections "Rainfall Intensity" and "Water Carrying Capacity and Rainwater Run-Off".

Maximum Roof Length (m)

Roof Slope
(degrees)
Rainfall Capacity (mm/hr)
100150200250300350400
341272016131110
448322419161312
554362721181513
Table CM21 RL NC 001 - CorroMax 21™ Non-Cyclonic
Notes:
  1. Minimum recommended slope is 3°. Sheet lengths greater than 24m are not recommended due to thermal expansion and contraction.

Load Span Tables

Wind Load Capacity: Limit State Design: 0.40mm BMT

Span (mm)Single SpanEnd SpanInternal Span
Serv. (kPa)Strength (kPa)Serv. (kPa)Strength (kPa)Serv. (kPa)Strength (kPa)
6001.4211.421.4910.471.3311.61
9001.249.501.316.901.178.50
12000.997.001.185.301.036.70
15000.885.201.104.320.905.50
18000.854.550.963.400.784.45
2100--0.812.650.703.55
2400--0.662.050.652.80
Table CM21 WC NC 001A - CorroMax 21™ Non-Cyclonic
Note:
  1. Values in the table above have been generated based on testing into steel supports with at thickness of 1.0mm.
  2. Values are based on no insulation under the sheeting.
  3. Serv. denotes serviceability

Wind Load Capacity: Limit State Design: 0.48mm BMT

Span (mm)Single SpanEnd SpanInternal Span
Serv. (kPa)Strength (kPa)Serv. (kPa)Strength (kPa)Serv. (kPa)Strength (kPa)
6002.7312.061.7111.871.8012.13
9002.4610.951.459.601.599.80
12001.858.931.238.031.408.10
15001.307.401.036.651.256.38
18000.926.150.895.481.134.88
2100--0.804.320.803.85
2400--0.743.320.743.20
2700--0.722.380.722.97
Table CM21 WC NC 001B - CorroMax 21™ Non-Cyclonic
Note:
  1. Values in the table above have been generated based on testing into steel supports with at thickness of 1.0mm.
  2. Values are based on no insulation under the sheeting.
  3. Serv. denotes serviceability

 

Figure SR NC 002 End Spans, Internal Spans and Overhangs illustrates the terminology end spans, internal spans, and overhangs and their reference to the supporting substructure. This terminology has been used in the following Maximum Recommended Span and Wind Load Capacity tables.

S-Rib™ Corrugated NON-CYCLONIC Figure SR NC 002 End Spans, Internal Spans and Overhangs

Figure SR NC 002 End Spans, Internal Spans and Overhangs

Maximum Recommended Roof Cladding Span

Wind
Region
Base Metal
Thickness
(mm)
Terrain Category 3
Single (mm)End (mm)Internal (mm)
B0.407509501350
0.4895015001900
Wind Loading Design Parameters
+
Design Life 50 years
Importance Level 2
Maximum Roof Height H = 10m
External Pressure Coefficient:
   Cpe = -0.65 for walling
   Cpe = -0.9 for roofing
Internal Pressure Coefficient:
   Cpi = 0.2
Local Pressure Factor:
   KL = 2.0 (end & single span)
   KL = 1.0 (internal span)

Table CM21 RS NC 001 - CorroMax 21™ Non-Cyclonic
Note:
  1. For roofs: the data are based on foot-traffic loading.
  2. Table data are based on supports of minimum 1mm BMT.

Maximum Recommended Wall Cladding Span

Wind
Region
Base Metal
Thickness
(mm)
Terrain Category 3
Single (mm)End (mm)Internal (mm)
B0.42180024002400
0.48180027002700
Wind Loading Design Parameters
+
Design Life 50 years
Importance Level 2
Maximum Roof Height H = 10m
External Pressure Coefficient:
   Cpe = -0.65 for walling
   Cpe = -0.9 for roofing
Internal Pressure Coefficient:
   Cpi = 0.2
Local Pressure Factor:
   KL = 2.0 (end & single span)
   KL = 1.0 (internal span)

Table CM21 WS NC 001 - CorroMax 21™ Non-Cyclonic
Note:
  1. For roofs: the data are based on foot-traffic loading.
  2. For walls: the data are based on pressures (see wind pressure table).
  3. Table data are based on supports of minimum 1mm BMT.

Pierce Fixing

Fasteners must be selected to match the life expectancy of the cladding material. Recommendations from fastener manufacturers should be sought.

Only fasteners complying with AS 3566:2002 and those that are compatible with the roofing material should be used for its fastening.

Pierce Fixing Table

Fixing SupportsCrest FixingValley Fixing
(Wall only)
Side Lap Fixing
Steel
1.0 to 3.0mm
12-14x35, Metal Teks HG, HH
or
AutoTeks 12.5-14x39
10-16x16, Metal Teks, HH
or
10-16x25 Designer Head
(If required) 10-16x16, Metal Teks, HH or Roof Zips M6-11x25 or 10-16x25 Designer Head or Sealed blind rivet ø4.8mm aluminium
Timber
Hardwood
12-11x50, Type 17 HG, HH10-12x25, Type 17, HH
10-16x25 Designer Head
or
12-11x25, Type 17, HH
Timber
Softwood
12-11x50, Type 17 HG, HH
or
Roof Zips M6-11x50 HG, HH
10-12x30, Type 17, HH
12-11x25, Type 17, HH
10-16x25 Designer Head
or
Roof Zips M6-11x25
Metal Battens
(0.55 to 1.0mm)
Roof Zips M6-11x5010-16x16, Metal Teks, HH
or
10-16x25 Designer Head
or
Roof Zips M6-11x25
Table CM21 PF NC 001 - CorroMax 21™ Non-Cyclonic

Fastener Spacings - Non-Cyclonic

Crest Fastener Location

S-Rib™ Corrugated NON-CYCLONIC Crest Fastener Location 3 Fasteners

3 Fasteners per sheet – Internal supports.
Roofing should be lapped away from the prevailing weather.

Valley Fastener Location (Wall Only)

S-Rib™ Corrugated NON-CYCLONIC Valley Fastener Location (Wall Only) 3 Fasteners

3 Fasteners per sheet – Internal supports.

Figure CM21 FS NC 001

Notes:
1. All fasteners used externally should be fitted with an EPDM seal (washer).
2. Do not use punches to form fastener holes.

Side Lap Fastening

It may be necessary to use side lap fasteners at mid spans when using S-Rib at maximum spans. These will help to hold the sheet laps firmly in place and maintain a weather-proof joint.

Insulation

Care needs to be taken when installing insulation with roof sheeting. When insulation thickness up to 50mm are installed the screws detailed in Table SR PF NC 001 may need to be increased depending on the thickness and density of the insulation. When the screw is properly tightened into metal there should be a minimum of three (3) threads protruding past the support being fixed in to. For timber the screw must penetrate the timber as much as the screws detailed in Table SR PF NC 001 do without insulation.

For insulation thicknesses greater than 50mm Fielders® recommend the use of a thermal spacer to help maintain Rw values as well as minimising any bulging in the profile caused by the insulation.

Curving CorroMax 21™

For details regarding spring, crank and smooth curving of CorroMax 21™ sheets, please see section Curving of Steel Decks”.

Curving quality corrugated is manufactured from G300 sub-strate (0.60 BMT). It is consequently more ductile, enabling specialist tradesmen using precision curving machines to form sheets to traditional heritage shapes and challenging architectural details down to radii as tight as 450mm. Fielders® have a dedicated roll forming machine for G300 thus avoiding any inconsistency arising out of changing over from G550 Hi-tensile coil.

CorroMax 21™ Installation Procedure

For installation procedures see section “Typical Pierce Fix Installation Guide”. For general handling instructions refer to section “Maintenance and Care”.

Figure CM21 NC Corrugation Laps 003

Maximum Sheet Length

Turning of Roof Sheeting Ends

Refer to section “Flashings, Cappings & Ends of sheets”.

Curving Orders

When ordering curved sheets, please state the following:

ZINCALUME®

Sheets

COLORBOND®

Sheets

Color

Sheets

Direction of laying (facing roof)

Left to right

Sheets

Right to Left

Sheets

Overall Length of Sheet (Allow 50mm into Gutters)

mm

Bullnosed

A

Radius (minimum 500mm)

mm

B

Pitch or fall

mm

D

Wall to outside fascia

mm

E

Straight length

mm

H

Height

mm

S-Rib™ Corrugated NON-CYCLONIC Figure SR NC Bullnosed Dimensions 004

Figure CM21 NC Bullnosed Dimensions 004

Concave

D

Wall to outside fascia

mm

H

Height

mm

X

Dip from Straight Line

mm

S-Rib™ Corrugated NON-CYCLONIC Figure SR NC Concave Dimensi 005

Figure CM21 NC Concave Dimensions 005

S-Rib™ Corrugated NON-CYCLONIC Bull Nosing

Bull Nosing

S-Rib™ Corrugated NON-CYCLONIC Curving to Underslung or Overslung

Curving to Underslung or Overslung

S-Rib™ Corrugated NON-CYCLONIC Radius Curve (Deep Curve)

Radius Curve (Deep Curve)

S-Rib™ Corrugated NON-CYCLONIC ‘S’ Curve

‘S’ Curve

S-Rib™ Corrugated NON-CYCLONIC Ridge Curve and Bullnoosing with extended straight section

Ridge Curve and Bullnoosing with extended straight section

S-Rib™ Corrugated NON-CYCLONIC Figure SR NC Typical Curves 006

Figure CM21 NC Typical Curves 006

Curved Flashings

COLORBOND® and ZINCALUME® steel roofing gives the designer or architect greater flexibility than other roofing materials. Fielders® curved flashings offer an attractive, watertight method of finishing off barges. Fielders® sheet-metal workshop uses either Pittsburgh or Snap-Lock seams to achieve a curved profile flashing. Acrylead and flexible Dektite flashings may also be used.

S-Rib™ Corrugated Non-Cyclonic Curved Flashings

S-Rib™ Corrugated Non-Cyclonic: Pittsburgh Lock-Seam and Snap-Lock

Figure CM21 NC Pittsburgh Lock-Seam and Snap-Lock 007

Curved Flashing Available Materials

FinishConforming to StandardBMTColour
ZINCALUME®AS 1397
G300-AZ150
0.50N/A
COLORBOND® XRWAS 1397 G300-AZ150
and AS 2728
0.50As selected
COLORBOND® UltraAS 1397 G300-AZ200
and AS 2728
0.55As selected
COLORBOND® StainlessGrade 430 base 3000.45As selected
Z600 Heritage GalvanisedAS 1397
G300-Z600
0.50N/A
Table CM21 CF NC 001 - CorroMax 35™ Non-Cyclonic

Hip Bracing

S-Rib™ Corrugated Hip Bracing

S-Rib™ Corrugated NON-CYCLONIC Figure SR NC Type A Hip Bracing 008

Figure CM21 NC Type A Hip Bracing 008

S-Rib™ Corrugated NON-CYCLONIC Figure SR NC Type B Hip Bracing 009

Figure CM21 NC Type B Hip Bracing 009

Hip Bracing Materials

FinishConforming to StandardBMTColour
GalvanisedAS 1397:2002
G300-Z450
0.95N/A
Table CM21 HB NC 001 - CorroMax 21™ Non-Cyclonic

Cappings

Refer to section Cappings”.