IBR has a fluted profile, where corrugated iron has a waved profile; IBR is used for various applications from roof covering to mainly cladding in industrial and commercial buildings. Being a household name and similar lifespan, causes more confusion with corrugated iron.
Approximate Life Span Years | ||||||
Thickness | 0.47mm | 0.40mm | 0.50mm | 0.58mm | 0.80mm | 0.80mm |
Rural area | >30 | >30 | >10 | >20 | >20 | >20 |
Industrial/Marine | >20 | >20 | 5-20 | 10-20 | 10-20 | 10-20 |
Severe Marine | 10-20 | 10-20 | 1-5 | 3-10 | 3-10 | 3-10 |
The wide range of IBR material is displayed by the properties and this property provides an indication of purlin spacing. Other factors is wind, dust etc. which will provide indication of purlin spacing. It is always recommended that a engineer is consulted before a building project commence or material is bought
Recommended Maximum Purlin Spacing Metre | ||||||
Thickness | 0.47mm | 0.40mm | 0.50mm | 0.58mm | 0.80mm | 0.80mm |
Steelgrade | G550 | ISQ300 | ISQ550 | ISQ300 | ISQ230 | ISQ230 |
Roof - Single Span | 1.65 | 1.25 | 1.65 | 1.75 | 2.25 | 1.20 |
Roof - Double Span | 1.95 | 1.40 | 1.95 | 2.10 | 2.50 | 1.50 |
Cantilever - Roof | 0.40 | 0.20 | 0.40 | 0.45 | 0.55 | 0.45 |
Wall Single Span | 2.35 | 1.70 | 2.35 | 2.60 | 2.95 | 1.80 |
Wall Double Span | 2.75 | 1.90 | 2.75 | 2.95 | 3.60 | 1.00 |
Cantilever | 0.90 | 0.60 | 0.90 | 1.00 | 1.15 | |
When a building project’s house plans e.g. Wendy house, carport or even a industrial building is being designed, roof pitch is one of the items which need the most attention as the various roof pitches and roof types will provide different looks for your project e.g. Flat roof/ lean too etc.: 3 º to 17º (single sheet long span can be used to keep to, as low degree as possible.) Gable, HIP and colonial roof types: 12º to 45º will be ideal, but on average 26º is ideal. Using IBR on the various roof pitches it is suggested to use 7.5 º pitches on slopes longer as 30m and slopes shorter than 30m the pitch to be 5º.
When long span single length sheets is NOT used the end & side overlaps should be taken in account as follow: End overlaps on pitches in exceeding 15º to be at least 150 mm, for lower roof pitches 250mm overlap is highly recommended. Side overlaps 100mm is recommended. On low pitched roof additional sealant for watertightness is suggested.
The required number of IBR sheets can be calculated as follows.Number of sheets = Length of building + gable end overhangs - 77 mm / 0.686 m (Cover width of sheet)
Roof sheets and vertical wall cladding should be laid with 1 corrugation side lap with the narrow flute uppermost and must be fixed through the crests of alternate flutes to purlins using 65 mm Top Speed or Tex screws into steel purlins e.g. carports and 90 mm Tex or Top Speed screws in the case of timber supports e.g. wendy houses and dwellings, all fasteners shall incorporate 26 mm dia bonded washers
Some technical information on corrugated Iron can be summarized as follow:
Ø Available in standard lengths up to 15 metres
Ø The permissible length tolerance for the standard length range will be -+5 mm
Ø Available in various Materials
Drawing Supplied 2011, by K. Burger Architectural draughtsmantechnical information | ||||||
Thickness | 0.47mm | 0.53mm | 0.40mm | 0.50mm | 0.58mm | 0.80mm |
Weight per metre | 3.195kg | 3.833kg | 2.897kg | 3.615kg | 4.197kg | 5.798kg |
Weight per square metre | 4.191kg | 5.030kg | 3.801kg | 4.744kg | 5.507kg | 7.608kg |
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 | ±0.02 | ±0.03 | ±0.04 |
