Steel windows are not a trend. They are a response to constraints. High wind zones require stiffness. Steel deflects less than aluminium at equivalent spans. That protects seals and glazing over time. Slim profiles are not just aesthetic. They allow more daylight without sacrificing strength. That matters in dense urban sites and heritage contexts. Steel performs under fire exposure. It suits boundary conditions and multi-unit buildings where fire separation is non-negotiable

In an era where energy costs are rising and comfort is paramount, the windows in your home or building play a pivotal role. They are the guardians of your climate, your peace, and your energy bills. Moving beyond standard solutions, we are proud to unveil our new range of high-performance aluminium windows—engineered not just to meet modern demands, but to surpass them.   Built on a Foundation of Strength & Sealing   At the core of our system is a high-strength aluminium fram

The South Island exposes weak window systems fast. Cold winters reveal thermal failures. High winds expose frame movement. Salt air accelerates corrosion. Frost highlights condensation risk. Many window systems sold in the South Island are designed for milder regions. They pass minimum code. They struggle in real conditions. Inland Canterbury and Otago demand insulation first. Queenstown and alpine regions demand stability under snow and wind. Coastal Otago and Southland dema

Longevity is predictable. Windows that last decades share the same traits: Stable frame materials. Proven hardware. Correct surface protection. Proper installation. Steel resists movement. Aluminium relies on correct design and fixing. Hardware quality affects daily use. Cheap components fail early and often. Installation errors cause most long-term issues. Flashings, tolerances, and packers matter more than brochures. A well-specified and well-installed South Island window s

Salt does not forgive mistakes. Coastal South Island environments accelerate failure when coatings are wrong or detailing is poor. Most corrosion issues are not material failures. They are specification failures. Common causes include: Incorrect coating class. Incompatible fixings. Poor drainage at junctions. Steel and aluminium both perform when specified correctly. Both fail when shortcuts are taken. Maintenance plans matter. So does access. The cheapest window is often the

Fire-rated joinery is a system, not a component. Steel performs well under fire exposure. Slim profiles remain achievable with tested assemblies . Fire ratings apply to the complete build-up. Frame, glass, seals, and fixings must match test data. Common mistakes include: Mixing untested components. Late fire separation changes. Treating fire joinery as standard windows. In South Island apartments and mixed-use buildings, fire-rated windows often sit on critical paths. Early

Passing H1 does not guarantee comfort. H1 sets minimum energy efficiency requirements. It does not ensure long-term performance. South Island projects often sit in higher climate zones. Window performance becomes critical. Thermal breaks, glazing, and airtightness work together. Weakness in one undermines the rest. Most compliance failures happen late. Windows are often selected after layout, budget, and consent pressure are already set. Early window decisions reduce redesign

Glass carries most of the thermal load. Double glazing is now the baseline. Alone, it is often insufficient in colder regions. Low-E coatings reduce heat loss. Argon fill improves insulation. These are proven technologies, not upgrades. Triple glazing suits: Queenstown. Central Otago. Inland alpine regions. Vacuum glazing delivers high thermal performance with slim profiles. It suits retrofit and heritage work where frame depth is limited. Glazing must match orientation. Sout

Aluminium dominates the South Island market. Performance varies widely. The difference is not brand. It is specification. Non-thermally broken aluminium transfers cold directly into interiors. Condensation follows. Comfort drops. Heating costs rise. High-performing aluminium systems use: Full thermal breaks. Multi-stage air seals. Correct glazing combinations. Stable fixing details. In Christchurch and Dunedin, wind-driven infiltration is a common failure point. Airtightness

While fire-rated steel windows carry a higher upfront cost than standard glazing, they are an investment in long-term building performance, life safety and compliance certainty. Increasingly, South Island construction, particularly commercial and multi-residential projects, cannot be consented without them. What Drives the Cost Achieving a certified fire rating requires specialist glass, reinforced steel joinery, thermal and structural testing, and installation to a documente

Specifying fire-rated windows is a process that begins long before installation. In the South Island, where seismic strengthening, densification and heritage upgrades are shaping the built environment, accuracy in specification is essential. Southern Windows works alongside architects, fire engineers and construction teams to ensure fire-rated steel systems are correctly selected, documented and installed to meet C/AS2 and AS1530.4 requirements. Understanding What Needs to Be

Fire safety is no longer a peripheral consideration in modern construction; it is a fundamental part of design. As multi-unit residential developments, commercial projects, and seismic upgrades accelerate across New Zealand, certified steel fire-rated windows have become a critical requirement. Southern Windows supplies fully tested systems designed to meet NZ Building Code C/AS2 and verified to AS1530.4, ensuring genuine performance for projects throughout Christchurch, Quee