Renovating in the Top End comes with its own unique challenges. Our tropical climate means homes must be designed—or re-designed—to stay cool, comfortable, and energy efficient.

While COOLmob already offers an excellent guide to Sustainable Tropical Design for new homes, this page focuses on renovations. Every upgrade is an opportunity to improve energy performance, whether you are:

• Replacing just your roof
• Upgrading windows
• Overhauling the building envelope
• Landscaping your garden

To download a copy of Design for the Tropics 

What to consider when renovating

• The Building Envelope: your home’s walls, roof, and floors — is the “skin” that protects you from heat. Light-coloured surfaces reflect more sunlight, while roof ventilation helps release trapped hot air. Sealing gaps around doors, windows, and walls prevents heat from entering and improves the efficiency of air conditioning
• Windows: Windows bring in light and breezes but can also let in unwanted heat. Use louvres or sliding windows to maximise cross-ventilation, and add external shading such as awnings, shutters, or deep eaves to block the sun before it enters. For improved efficiency when the house is closed up, consider double glazing or solar films
• Insulation: Insulation is essential in the Top End for keeping heat out and cool air in. Roofs benefit from R3.5–R4.0 bulk insulation, with sarking or reflective foil added to reduce radiant heat. Where possible, retrofit walls with bulk insulation batts for greater comfort.
• Air Gaps: Older Top End homes often relied on gaps for airflow, but in modern renovations these same gaps let cooled air escape. Seal around windows, doors, and floors, and install quality seals to allow the house to “shut down” when using AC. Screen doors are a good way to maintain airflow while keeping insects out.
• Passive Cooling: Passive design reduces the need for mechanical cooling. Align openings to create cross-ventilation, use high-level louvres or clerestory windows to let hot air rise and escape, and position ceiling fans strategically — the simplest, most cost-effective comfort upgrade.
• Efficient Air Conditioning: During the Build-Up or Wet season, air conditioning is often essential. To use it efficiently, insulate and seal the home so cool air doesn’t leak. Zoning or split systems allow you to cool only the rooms in use, while curtains and blinds reduce heat transfer through windows.
• Shade: Shade is the first and most effective defence against heat. Deep verandas and covered decks protect walls and windows, while trees and landscaping lower surrounding temperatures. Pergolas and shade sails offer flexible options for quick upgrades.

Read more: 

Thermal Performance Basics

Renovation Action Plan

Why energy efficiency matters

1. Lower Energy Use = Lower Bills
   Renovated homes with improved insulation, shading, and airtightness use significantly less energy. That means smaller power bills—especially crucial in the Top End, where electricity costs are already above the national average.

2. Comfort Without Air Conditioning
   A well-upgraded home stays cooler naturally. It's more comfortable, meaning you will use the AC less. 

3. Our Climate Is Heating Up—Fast
   • The Top End is already seeing more extreme heat. Under a high-emissions scenario, the number of extreme heat days (>35 °C) may nearly double. 
   • A Health Heat Risk Index has identified areas in the Top End as being in the highest risk category for heat impacts.
   • Outdoor workers in the Northern Territory are increasingly affected by extreme heat, with projections indicating significant challenges to labor capacity by 2070 due to rising temperatures. Likewise, it is essential that residents can return to homes that remain safe, comfortable, and energy-efficient, providing relief from extreme heat without imposing excessive energy costs.

Explore the Climate Council's Climate Heat Map of Australia. What is predicted for your suburb?