Metal Roofing

Metal roofing refers to roofs using the materials:

• Colorbond steel
• Zincalume steel
• Galvanised iron

At Reliance, we can install all 3 kinds of metal roofing material. Choose from Colorbond in the colour of your choice, the traditional look of Zincalume or Galvanised iron roofing. We are fully licenced in all areas of metal roofing (“roof plumbing”) and only employ roofers who also hold their own BSA licences, and meet our strict performance requirements. There will always be a licenced roofer who has met our standards on site when you have your roof replaced with Reliance. This is your “peace of mind” that your new roof will be installed to the highest standards of workmanship, and exceed standards set by the Queensland Building Services Authority (QBSA). Below are descriptions of each of the roofing options and how each may benefit you.

Colorbond steel:

This is the most popular (metal) roofing material used on new homes these days. It’s sleek lines, and range of popular colours can make a Colorbond roof a very attractive option for many homes. In fact, Colorbond is fast catching up to tiles as the most commonly used roofing material on new houses Australia wide, and especially here in Queensland.

Colorbond is custom length, and made from high tensile steel in .42 or .48 BMT (base metal thickness). Colorbond also comes in ‘Blue orb’ curving quality steel which is .6 BMT and commonly used for curved roofs or bullnoses.

Zincalume Steel:

Zincalume is a popular choice for older homes trying to restore the traditional looking roof. Zincalume is silver in colour and is an attractive style of roof for old Queenslander homes, Colonial style and many post-war style houses.

Zincalume is made from high tensile steel in .42 or .48 BMT (base metal thickness). Zincalume is also made in .6 BMT for curved roofs and bullnoses.

Galvanised Iron:

Dating back hundreds of years, Galvanised iron was once the only metal roofing material used on homes. This material is what is often referred to as the old corrugated iron roof. Galvanised iron is not commonly used these days, most people wanting the traditional looking roof will opt for Zincalume, but you can still get “Gal”.

Anyone heritage listed buildings that get the roof replaced, will have it replaced with Galvanised iron.

Galvanised iron is made from -
Peter, can you try and source this info from other sites – try Lysaght, Fielders, Stramit etc

PROFILES

1. Custom orb – Commonly referred to as “corro”, this is your traditional corrugated profile and is the most popular profile used. Appropriate for roofs over 5 degrees pitch. Unless you have a roof with a pitch flatter than 5 degrees, you would most likely use this profile. Popular opinion is that this is the most attractive of the metal roof profiles.

2. Trimdeck – Typically used on flatter roofs between 2 and 5 degrees pitch, Trimdeck has a square shape to its corrugations with wide flat pans allowing for more water carrying capacity than corro.

3. Kliplok – Typically used on very flat roofs, this is a concealed fixed sheeting where screws are not visible from the top. Fixing clips secure the sheets to the supports from underneath the roof sheeting. No exposed fasteners means clean smooth lines and maximum water tightness. These factors, plus the deep wide pans and high narrow ribs, make Kliplok perfect for for flat roofs. .42BMT (base metal thickness) can be used on roofs as flat as 2 degrees, and .48BMT Kliplok can be used down to 1 degree.

FASTENERS

For Custom orb, typically 50mm tech screws with neoprene washers are used to fix roof sheeting and flashings to supports. Where no underlying support exists but fixings are necessary, “stitching” screws are required. These are typically 16mm or 25mm tech stitching screws.

Trimdeck uses 65mm tech screws.

Kliplok requires special fixing clips which are fixed to the underlying supports with standard tech screws, the the sheets clip on to the fixing clips and the sheets interlock with each other.

Note: Timber tech screws should be used for timber supports, and metal tech screws for metal supports. You can, however, use ‘Roof Zips’ which will fix to either metal or timber, however, these are not suitable for hard wood or some heavy duty thicker steel purlins.

How Many Fixings Required :

For Custom Orb or Trimdeck, the top and bottom row of each section should have a screw in every second rib. For the centre rows of battens you can screw every second rib, or as a minimum, follow a 2, 3, 3, 2  pattern.

Note: ALL battens should be fixed to using the above formula.

COVERAGE

Custom Orb and Trimdeck – Each sheet is 762mm wide allowing for overlaps. This means to calculate how many sheets are required to do, say, one side of your house, you need to divide the length by 762mm to know how many sheets are required.

Kliplok – Each panel is 700mm wide.

FLASHINGS AND CAPPINGS

Roofs with ridges and hips will require ridge and hip capping. These are in .6BMT heavy guage steel (Colorbond, Zincalume or Galvanised Iron).

For gables and the edges of a skillion style home, either edge roll should be used to “finish” off the edges, or custom made barge capping. These are also in .6BMT.

Flashings are required where there is a change of pitch, where a roof meets a wall or other penetrations. Flashings can be in either .4BMT, .5, or .6.

CALL US FOR A FREE QUOTE

Call Reliance for a free quote on replacing your roof. You’ll be placed under no obligation and our quote will be fair. Call (07) 3286 3900.