IBR Sheeting

IBR is a square fluted profile with an effective covering width of 686 mm designed for use as side cladding or roofing material in commercial, industrial and residential buildings. The name IBR is abbreviated from “Inverted Box Rib” and has become a household name in the South African building industry. The deep broad flute design offers excellent drainage characteristics combined with optimum weight versus load/span capabilities. IBR can be factory cranked, curved and bullnosed to various radii depending on customer's requirements.

Structural Guidelines

IBR roof sheets are available in a wide range of materials displaying various structural properties. It should be noted that the load span characteristics are only to be used as a broad guideline as purlin spacing is also dependant on other factors such as the prevailing winds in a certain area, snow during winter periods, the presence of dust and other particles in industrial areas, the type of structure that is being erected etc.. We therefore recommend that an engineer is consulted to determine the purlin spacing for a specific application.

Recommended Maximum Purlin Spacing (meter)
Thickness	0.47 mm	0.53 mm	0.40 mm	0.50 mm	0.58 mm	0.80 mm
Steel Grade	G550	G550	ISQ300	ISQ550	ISQ300	ISQ230
Roof - single span	1.65	1.75	1.25	1.65	1.75	2.25
Roof - double span	1.95	2.10	1.40	1.95	2.10	2.50
Cantilever - roof	0.40	0.45	0.20	0.40	0.45	0.55
Wall - single span	2.35	2.60	1.70	2.35	2.60	2.95
Wall - double span	2.75	2.95	1.90	2.75	2.95	3.60
Cantilever - wall	0.90	1.00	0.60	0.90	1.00	1.15
Weight per meter	3.194 kg	3.833 kg	2.897 kg	3.615 kg	4.197 kg	5.798 kg
Weight per sq metre	4.655 kg	5.587 kg	4.223 kg	5.269 kg	6.118 kg	8.451 kg
Coating type	Zincalume	Zincalume	Galvanised	Galvanised	Galvanised	Galvanised
Coating weight	AZ150	AZ150	Z160	Z275	Z275	Z275
Paint system	Colorbond	Colorbond	N/A	Chromadek	Chromadek	Chromadek
Thickness tolerance	+/- 0.03	+/- 0.04	+/- 0.02	+/- 0.03	+/- 0.04

Approximate life span (years)
Thickness	0.47 mm	0.53 mm	0.40 mm	0.50 mm	0.58 mm	0.80 mm
Steel Grade	G550	G550	ISQ300	ISQ550	ISQ300	ISQ230
Rural area	>30	>30	>10	>20	>20	>20
Industrial / Marine	>20	>20	5 - 10	10 - 20	10 - 20	10 -20
Severe marine	10 - 20	10 -20	1 - 5	3 -10	3 - 10	3 - 10

Available Dimensions

IBR sheeting is available in standard lengths of 1.5 to 14 metres although a length up to 20 metres is available on request. The permissible length tolerance for the standard length range will be -0 +5 mm. Sheets outside these parameters are available on request and might be subject to special pricing arrangements. The maximum height which can be transported is 4.3 metres. This factor should be taken into account when bullnoses and curves are designed.

Roof Pitch

When using IBR, the recommended minimum pitch for roof slopes in excess of 30 m is 7.5º and for slopes less than 30 m is 5º.When IBR roof sheets are end lapped the roof pitch should be taken into account. The minimum end laps for roofs pitches in excess of 15º is 150 mm and for other roofs a minimum of 250 mm is recommended. End laps for side sheeting should be at least 100 mm. It is recommended that end and side laps on low pitch roofs are sealed to ensure watertightness.

Specification

Clotan Steel IBR (with/without) integral stiffening rib (*zinc coating) steel roof sheeting and accessories fixed to (timber/steel) purlins or rails with a (*refer to table) spacing. All sheeting is to be clearly marked on the reverse side at one-metre intervals indicating thickness, material quality and coating thickness.

Thickness & Material Quality	Coating	Available Paint System
0.40 mm - ISQ300	Z160 Galvanised
0.50 mm - ISQ550	Z275 Galvanised
0.58 mm - ISQ300	Z275 Galvanised
0.80 mm - ISQ230	Z275 Galvanised

0.50 mm - ISQ550	Z275 Galvanised	Chromadek
0.58 - ISQ300	Z275 Galvanised	Chromadek
0.80 - ISQ230	Z275 Galvanised	Chromadek

0.47 mm - G550	AZ 150 Zincalume
0.53 mm - G550	AZ 150 Zincalume	Colorbord

Clotan Steel IBR (with/without) integral stiffening rib (*zinc coating) steel roof sheeting and accessories with (Chromadek/Colorbond) finish on one side and protective primer coating on the reverse side fixed to (timber/steel) purlins or rails with a (*refer to table) spacing. All sheeting is to be clearly marked on the reverse side at one-metre intervals indicating thickness, material quality, coating thickness and paint system.

Installation Procedure

The required number of IBR sheets can be calculated as follows:

Number of sheets = Length of building + gable end overhangs - 70 mm

Roof sheets must be laid with one corrugation side lap with the narrow flute uppermost and shall be fixed through the crests of alternate flutes to purlins using 65 mm Top Speed or Tex screws into steel purlins and 90 mm Tex or Top Speed screws in the case of timber roofs, all fasteners shall incorporate 26 mm dia bonded washers.

For vertical wall cladding (side cladding) it is recommended that the broad fluted are fixed externally with the main and side lap fasteners in the web of the flutes. Side cladding can be fixed using 25 mm Tex or Top speed screws, all fasteners shall incorporate 26 mm dia bonded washers.

In order to qualify for a guarantee on Zincalume and Colorbond sheets the following fasteners supplied by Buildex Industries should be used: Metaltex Climaseal 3 for steel purlins and Timbertex Zacs 4 for timber purlins. The use of these fasteners will dramatically increase the lifespan of the roof sheeting as corrosion caused by fasteners is avoided.