Choosing A New Roof

A new roof is a big investment, so be certain to choose one you want to live with for the next 50 years.

If the roof needs to be replaced, do the homework to choose the best style and material for the home, comparing prices and installation costs.

Collect images of the style you like from websites, blogs, display village brochures and magazines to use as a reference when making decisions.

The material affects your entire home. It should look good, withstand the local climate, resist wear and tear, and insulate against sound and heat.

TIP: Check with local council to see if you’re restricted from using certain materials or colours.

The supporting structure of a roof can be a variety of shapes.

The degree, pitch or slope is an important consideration.

A flatter roof pitch maximises internal height while a steeper pitch allows for faster runoff in wet areas.

Hipped roofs have all the sides sloping down toward the walls.

Gabled is triangular in shape between sloping sections that meet at a peak.

Skillion is single-pitched with a flat sloping surface like the roof of a shed.

Convex has a simple curved shape that looks like an upside down U.

Cranked forms a continuous roofline with a curve on top instead of a ridge.

Sarking is a layer of flexible insulation installed under the roof battens when the home is being built.

Aluminium foil is laminated onto paper or plastic backing with a flame retardant adhesive and fibreglass mesh.

Sarking helps keeps a home insulated from summer heat while retaining warmth in winter.

It’s water resistant and weatherproof, stops condensation and is fire retardant as well as being thermally reflective.

TIP: Ensure the sarking you buy complies with the Building Code of Australia, specifically with AS/NZS 4200.1.

Cement-based tiles have been around for more than 150 years and have a lifespan of 30 to 50 years.

They’re strong and suited to all areas and climates, including harsh coastal locations, and while the colour of the tiles is prone to fading they can be resprayed.

“Concrete tiles offer a wide selection of profiles and colours with options to suit a range of budgets,” says Glen Simpkin from Boral.

TIP: The weight of a concrete-tiled roof increases after rain.

Terracotta tiles are lightweight and low-maintenance, and can last from 20 to 75 years.

They also feature a vitreous coating that helps them withstand UV and pollutants.

“The colour in terracotta will never fade,” says Linda Tadrosse from CSR Roofing.

They need to be handled carefully during installation to avoid chipping corners and cracking tiles.

Adding reflective foil in the roof, called sarking, improves energy efficiency.

TIP: New colour doesn’t stick to the glazed tiles, so they can’t be resprayed.

Slate tiles are the most durable roofing material with some slate roofs in Europe lasting up to 400 years.

“Slate increases the value of a property, it’s a collectable investment. Slate tiles removed from a 150-year-old roof have a good resale value,” says Sandy Yeates from Bellstone Stone and Slate Specialists.

When lifespan is taken into account they’re not so expensive but maintenance also costs as fixing slate isn’t a job for the average DIYer.

TIP: Matching damaged slates can be hard as no two slates are identical.

DIY-friendly slate solution

Fixing slate isn’t usually a job for the average handyperson but new products like Tapco Inspire from Bellstone are changing the rules.

The tiles feature guidance for nail placement and overlap. It looks like traditional slate but it’s cheaper, weighs less and is quicker to install.

“Once Australian builders adjust to installing these slates we believe it could shave $60 to $80 off costs per metre,” says Sandy Yeates.

The corrugated iron sheeting that used to cover the outhouse is no more.

Modern metal roofing is strong, light and has a low thermal massso it cools quickly on a hot night, improving comfort inside, and lasts a minimum of 25 years.

“Steel is lightweight yet extremely strong and durable. And its superior oven-baked finish resists chipping, peeling and cracking, plus, it comes in a wide range of colours,” says Lisa Dent of BlueScope Steel.

When installing metal roofing insulation is essential and contact with lead, copper and CCA-treated timber must be avoided.

Care must be taken when cutting, all metal filings should be removed to prevent rust pitting and cut ends must be refinished.

TIP: Compare metal profiles online at Steel Select.

Insulating a metal roof is crucial to reduce heat load and penetration of noise into metal-roofed homes.

This layer is sandwiched between the roof battens and roof sheets. It’s made from a blanket of bio-soluble glass wool fibres backed with a double layer of aluminium.

The thermal resistance of insulation, or how well it stops heat transfer, is expressed as an R value, with higher R values representing better insulating properties.

Hiring a professional early on means they can contribute information during the decision-making process.

Search online for a roofing company or try the Yellow Pages, or talk to manufacturers and suppliers such as BlueScope Steel, CSR Roofing and Boral for advice.

The best choice usually comes via recommendations with finished results you can inspect.

Be sure to look at previous work or speak to a former client before making a commitment.

To cost the job get written quotes with full details of the materials to be used and work to be done including the removal of waste.

Some tradies give you a rough cost estimate over the phone using Google Earth to measure and price your roof.

TIP: Remember that the cheapest price isn’t always the best option.

Here are the terms you need to know.

Ridge is the apex or peak of a roof where the inclined sides meet and is usually covered with a ridge capping.

Roofing battens are timber or metal members to which roofing material is secured.

Barge capping is a tile or metal capping that overlaps and waterproofs the exposed edge of a gable roof.

Matching the material to the home

Choosing a tiling material depends mostly on design preferences.

“Profiles are synonymous with different styles of home,” says Michael Monro from Bristile Roofing, so be mindful of making a selection that suits your architecture.