When building a Stratco Outback verandah or patio, one of the first decisions is roofing material. The two most popular options are standard Outback Deck (a flat steel panel) and Cooldek (an insulated panel with a smooth underside).
Both are engineered for Australian conditions with Stratco’s 25-year structural warranty. But they perform differently in heat, noise and aesthetics — and the price gap is meaningful.
The Key Differences
| Feature | Outback Deck (Standard) | Cooldek (Insulated) |
|---|---|---|
| Construction | Single steel sheet, ribbed underside | Steel top + polystyrene core + smooth steel underside |
| Underside Finish | Visible ribs and fasteners | Smooth, flat, ceiling-like finish |
| Heat Reduction | Minimal — steel conducts heat directly | Up to 22°C cooler than standard steel |
| Rain Noise | Noticeable — rain on steel is loud | Significantly reduced — insulation dampens noise |
| Max Span | Up to 8.4m (Type 4) | Up to 4.5m (wider spans need purlins) |
| Cost Premium | Base price | 30–50% more than standard |
| Best For | Budget projects, carports, utility areas | Entertaining areas, outdoor dining, living extensions |
Temperature Performance: The Real Difference
This is the main reason most clients upgrade. Melbourne summers regularly hit the high 30s and low 40s. On a 38°C day, a standard steel roof can reach surface temperatures above 65°C, and the radiant heat underneath makes the space uncomfortable.
Cooldek’s polystyrene core reduces the underside temperature by up to 22°C compared to uninsulated steel. Across hundreds of installations, the temperature difference is the single most commented-on upgrade by clients after their first summer.
Noise: A Bigger Factor Than Expected
Rain on an uninsulated steel roof is loud. For a covered entertainment area where you want conversations during a downpour, standard roofing can be a problem. Cooldek’s insulated core absorbs rain impact, reducing noise to comfortable conversation levels. If your patio sits next to a bedroom or living room, this benefits the interior too.
Aesthetics: Ceiling-Like vs Industrial
Standard Outback Deck is clean and functional from above, but the underside shows ribs, purlins and fasteners. It’s fine for carports and utility areas.
Cooldek presents a smooth, flat, white underside that looks like plasterboard ceiling. Combined with recessed downlights and a ceiling fan, a Cooldek verandah feels like an indoor room that happens to be outside. For projects where the patio is a genuine living extension, this finish makes a significant visual difference.
Cost: Is the Upgrade Worth It?
Cooldek adds 30–50% to the roofing component cost. On a mid-sized verandah (4m × 6m), that’s roughly $2,000–$4,000 additional.
For carports, storage or utility covers: standard flat roof is the sensible choice. For entertaining, dining or any space where you’ll spend extended time: Cooldek pays for itself in comfort within the first summer.
Our Recommendation
- Carport, side passage, utility area → Standard Outback Deck
- Outdoor dining, alfresco entertaining, BBQ area → Cooldek
- North or west-facing (maximum sun) → Cooldek strongly recommended
- Budget priority → Standard now, upgrade later if structure is engineered for it
Frequently Asked Questions
Can I upgrade from flat roof to Cooldek later?
It depends on the existing structure. If beams and footings were engineered for Cooldek’s weight, the upgrade is straightforward — existing sheets removed and replaced. If not, beam upgrades may be needed. We recommend specifying Cooldek capability at design stage even if installing standard initially.
What colours does Cooldek come in?
All standard Colorbond colours, with topside matching your choice and underside in smooth white. Most popular: Surfmist, Dune, Monument and Basalt.
Does Cooldek come with a warranty?
Yes. 25-year structural warranty and 8-year paint finish warranty from Stratco. Plus our 1-year installation warranty as an authorised dealer.
