25 Undercliffe Street, Dee Why
Award-winning coastal masterpiece of sustainable design, north-facing ocean views
A showcase of contemporary coastal design and environmental innovation, this award-winning home on Undercliffe Street redefines sustainable luxury. Winner of the 2025 HIA GreenSmart Home of the Year, it stands as a benchmark for integrity, design excellence and performance. Designed and built to certified Passive House EnerPHit standards, the home retains and reimagines its original structure, combining architectural sophistication with an exceptional commitment to sustainability. Powered by a 10kW solar system and 12kW battery, it functions largely off-grid, with intelligent energy automation ensuring year-round comfort and efficiency. Every finish has been carefully chosen for ethical, low-emission or recycled credentials, while the architecture itself embraces its north-facing block with spectacular ocean and district views, and natural materials that blend seamlessly into the coastal setting. With open-plan living flowing to an ocean-facing terrace, landscaped gardens, a private teen or guest retreat and a serene master suite, this is elevated coastal living, delivering a beautifully balanced fusion of form, function and conscience. - Architectural home designed to Passive House EnerPHit standards - Award-winning 2025 HIA GreenSmart Home of the Year residence - North-facing block capturing panoramic ocean and district views - Sustainably built using Global Greentag and FSC-certified materials - Operates almost off-grid via 10kW solar system and 12kW battery - High-performance HVAC with filtered, temperature-controlled airflow - Open-plan living and dining extends to ocean-facing entertaining terrace - Master retreat with study, ensuite and access to private rear garden - Retreat level with three bedrooms, wet bar and private north balcony - Pristine bathrooms with underfloor heating and additional powder room - GreenTag-certified flooring, cabinetry, paint, tiles and carpets throughout - Double-glazed German windows ensure comfort and acoustic insulation - Rainwater collection tanks, organic waste systems, green roof garden - Recycled concrete aggregate and carpet made from recycled fish nets - Double garage with EV charger, mezzanine storage and mini gym - Moments to Dee Why and North Curl Curl beaches, cafés and transport - Multiple living areas and generous proportions offer flexibility for households, with the potential for dual occupancy, multi-generational living or private teenage retreat
Get to know the area.
Life revolves around the beach in this laid-back yet bustling Northern Beaches hotspot. Dee Why blends its multicultural makeup and lively shopping district with the laid-back surfie vibe along popular Dee Why beach – a trait that has long been capturing the attention of Sydneysiders.
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Belle Property Dee Why is a name synonymous with residential/commercial sales and property management on Sydney’s dynamic Northern Beaches.
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