The quick comparison
| Factor | Colorbond steel | Concrete tiles | Terracotta tiles |
|---|---|---|---|
| Weight | Light | Heavy | Heavy |
| Installed cost | Usually lowest | Middle | Highest |
| Minimum pitch | Low pitches possible | Needs steeper pitch | Needs steeper pitch |
| Rain noise | Louder unless a blanket is used | Quiet | Quiet |
| Heat | Depends on colour and blanket | Thermal mass | Thermal mass |
| Salt air | Grade and fixings critical | Tiles fine; fixings and flashings need care | Tiles very durable |
| Upkeep | Wash sheltered areas near sea; check fixings | Re-pointing, surface wear | Re-pointing, valleys |
| Look | Modern or traditional profiles | Classic suburban | Traditional, colour lasts |
For actual prices, see the cost guide.
Where steel wins
Weight
Steel weighs a fraction of tiles. On older frames, that reduces load. Tile-to-steel conversions rarely need structural upgrades for the roof itself.
Low pitches and modern designs
Steel can be laid on roofs too flat for tiles, which is why skillion and low-pitch homes use it.
Fewer joints
Long sheets running from ridge to gutter give wind-driven rain fewer ways in compared with hundreds of overlapping tiles.
Speed of installation
Steel goes on faster, which matters in storm season when every dry day counts.
Where tiles win
Quiet
Tiles are quieter in heavy rain and hail. A blanket under steel narrows the gap a lot, but tiles keep an edge.
Thermal mass
Tiles absorb heat slowly and release it slowly. That can smooth temperature swings, though it also means some heat is released into the evening.
Look and street character
On many established streets of brick-and-tile homes, tiles keep the look consistent. Terracotta's colour does not fade.
Durability of the tiles themselves
Terracotta tiles in particular can last a very long time. Concrete tiles are durable but their surface wears.
Where each has weak spots
Steel
- Coating grade and fixings must suit the site's distance from the sea.
- Needs a blanket or membrane for noise and condensation.
- Incompatible metals and leftover swarf cause corrosion.
- Dark colours absorb a lot of heat.
Tiles
- Heavy and slower to install.
- Ridge bedding and pointing need periodic attention.
- Concrete tile surfaces erode and become porous in sun and humidity.
- Need adequate pitch.
- Brittle under foot traffic from other trades.
Coastal and hinterland considerations
Near the beach, steel is often still the best choice, but only with the right grade and fixings. Tiles are less sensitive to salt, though their fixings and flashings still are. In the cooler, wetter hinterland, tiles can grow moss on shaded faces, while steel needs good condensation control. In mapped bushfire-prone areas, construction requirements may affect either choice.
Approvals
Changing from tiles to steel, or the reverse, may need building approval depending on the extent of work and its effect on structure. Body corporates, covenants and heritage overlays may also apply. Check before committing; see roofing regulations in QLD.
What the conversion involves
If you decide to switch from tiles to steel, it helps to know what changes on the roof. The tiles and old battens come off. New battens go on at the wider spacing steel needs, fixed to suit the site's wind classification, and in some cases the tie-down of the roof frame to the walls is checked and upgraded. A roof blanket goes down, then the sheets, ridge and hip capping, and new flashings at walls, chimneys and penetrations. Gutters are often replaced at the same time.
Going the other way, from steel to tiles, is less common and usually requires an engineer or certifier to confirm the frame can carry the extra weight. Either way, ask whether building approval is needed before you commit, and make sure the quote covers every one of these steps.
How to decide
- Is the site close to the sea or highly exposed to wind?
- What pitch is the roof?
- How much do rain noise and street character matter to you?
- What is the budget for this stage?
- How much maintenance will you realistically do?
If your answers lean toward a light, economical, low-maintenance roof that suits a low pitch, steel is likely the fit. If quiet and traditional appearance matter most and the pitch suits, tiles may be. For more, see Colorbond roofing and tile roof replacement.
General information for Sunshine Coast property owners, not advice about your particular roof. Rules, products and programs change; confirm with the authority named, or with Sunshine Coast Council or Noosa Shire Council, before acting.