Polycarbonate Greenhouse

Create a more controlled and reliable growing environment with our range of polycarbonate greenhouses. Designed for New Zealand conditions, these greenhouses offer excellent insulation, durability, and plant protection, making them ideal for year-round growing.

 



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Steelmates Greenhouse Features

Our greenhouse range is well designed with the following features

  • Wind Resistant

    Most garden greenhouses are glazed with the wile-clip method, which involves clipping the plastic sheeting directly to the frame. However, this is not ideal for use in windy conditions. Our slot-in greenhouse has a good anti-wind performance, it keeps your greenhouse insulated and stable, even in harsh weather conditions, which is a better choice for New Zealand customers.

  • Rainwater Collection

    Our greenhouse is designed with sustainability and the environment in mind. Its features allow you to collect and recycle rain to water your plants. This means less water is wasted and our planet benefits.

  • Easy Maintenance

    We provide a 3-year warranty for the panel and a 5-year warranty for the frame. Besides, the screws and nuts are stainless steel, which makes the greenhouse easy to maintain.

  • Premium Material

    Compared with glass material, our greenhouse is made of polycarbonate sheets that are lighter, and tougher. The thickness of the sheets is up to 6 mm, which makes the polycarbonate greenhouse more durable and stable. Besides, the light gets more evenly distributed to what would be darker areas in your greenhouse, which ensures your plants enjoy enough sunlight and grow lushly.

Polycarbonate Greenhouse or Glasshouse?

Find the right growing space for your garden. Compare warmth, natural light, durability and appearance to choose the option that suits your needs.

Polycarbonate Greenhouse or Glasshouse?
Features
2.4m x 4.4m The Ultimate Greenhouse 6mm Twin Wall Aluminium Greenhouses Steelmates
Polycarbonate Greenhouse
Lightweight, impact-resistant panels retain warmth and soften sunlight, helping vegetables, herbs and seedlings thrive.
PC Curved Glasshouse 4mm toughened glass 2640 x 3830 x 2550mm Glasshouses Steelmates
Toughened-Glass Glasshouse
Enjoy natural light, clear views and timeless style with a toughened-glass growing space for your garden.
Insulation & Heat Retention Insulating air pockets help retain warmth and reduce heat loss during cooler weather. Single-pane glass provides less insulation, allowing heat to escape more quickly.
Natural Light Diffuses sunlight for softer, more evenly distributed light and fewer harsh shadows. Clear glass allows more natural light through; frosted roof options soften incoming sunlight.
Growing Season Better heat retention helps support growing into cooler months. Excellent light transmission supports growing when daylight is limited; additional warmth may be needed.
Impact Resistance Highly resistant to accidental knocks and impacts, with a low risk of shattering. Stronger than ordinary glass, but can still break under severe impact.
Safety Lightweight glazing that does not shatter like glass. If broken, toughened glass breaks into small fragments, reducing injury risk compared with ordinary glass.*
Appearance & Visibility Practical garden appearance with translucent panels that soften the view inside. Clear views and a classic, premium finish that makes an attractive garden feature.
Heating Efficiency Better insulation can reduce heating requirements when maintaining a set temperature. Greater heat loss can increase heating requirements during colder months.
Installation & Handling Lightweight panels are easier to lift and position during assembly. Heavier panels require careful lifting, handling and installation.
Cleaning & Maintenance Clean gently with a soft cloth and a suitable mild cleaner to avoid scratching. Smooth, scratch-resistant glass is easy to clean and maintains its clarity well.
Long-Term Glazing Condition Panels may scratch or weather over time; lifespan depends on quality and exposure. Glass retains its clarity over time and does not yellow with sun exposure.
Summer Ventilation Requires ventilation and, when necessary, shading to manage heat. Requires ventilation and, when necessary, shading to manage heat.
Best For Gardeners prioritising insulation, impact resistance and value. Gardeners prioritising natural light, lasting clarity and garden aesthetics.
Product links View Poly Greenhouse View Glasshouse

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Greenhouse FAQ

Answer common questions about the aluminium greenhouse. Can't see it? Try searching keywords.

WHAT IS THE BENEFIT OF HAVING A GREENHOUSE?

The Steelmates greenhouses extend your growing season, add a variety of plants, and protect them from all weather conditions. 

IS THE POLYCARBONATE SHEET UV TREATED?

All Steelmates greenhouses come with UV treated polycarbonate sheets. 

WHAT TOOLS ARE NEEDED TO ASSEMBLE STEELMATES GREENHOUSES?

With our smart design, Steelmates greenhouses are assembled with a single wrench. No holes need to be drilled. An impact wrench will definitely speed up the process. 

DO YOU HAVE ONE ON DISPLAY?

Yes, we have a fully assembled greenhouse on display in our Auckland store. 

HOW EASY IS IT TO ERECT A STEELMATES GREENHOUSE

All Steelmates greenhouses come with easy to follow step by step instructions. No special tool or skill needed. If you don't have time, we also have contractors who can assemble for you nationwide.

WHAT IS THE BASE MADE OF?

The Steelmates greenhouses do come with a base, you can plant out of ground inside. You can add the foundation kit with your greenhouse, with the foundation kit, it saves a lot of effort to make the base of the greenhouse leveled and square.

DO YOUR GREENHOUSES COME WITH FOUNDATION?

All of our greenhouse comes with a foundation frame with 4 pegs.

WHAT IS THE THICKNESS OF THE POLYCARBONATE PANELS?

They come in 4mm or 6mm depending on the model

WHAT IF I NEED A REPLACEMENT PANEL?

We can supply replacement polycarbonate sheets to our customers.

HOW DO I PREVENT OVERHEATING IN MY GREENHOUSE DURING THE SUMMER?

Use manual vent to allow ventilation. You can also add auto vent opener at additional cost.

WHAT ARE THE ADVANTAGES OF GREENHOUSE FARMING?

Extended Growing Season: greenhouse enable you to extend the natural growing season of various plants, providing opportunities for year-round cultivation.

WHAT TYPES OF PLANTS CAN I CULTIVATE IN A GREENHOUSE?

Our greenhouses offer a perfect environment for a diverse array of plants, from common vegetables like tomatoes and cucumbers to exotic flowers and herbs. This controlled setting allows for consistent gardening success throughout the year.

WHAT ARE THE DIFFERENT TYPES OF GREENHOUSES AVAILABLE?

We offer a variety of greenhouse structures, including glass, polycarbonate panels, and plastic film options:

Glass: Offers durability and clear visibility but can reduce thermal efficiency.

Polycarbonate: Provides excellent insulation and is impact-resistant, although it may require replacement over time due to wear.

HOW DO I SELECT THE IDEAL LOCATION FOR MY GREENHOUSE?

Choose a location that receives ample sunlight, ideally with the longest side of the greenhouse facing north to maximize light exposure. Ensure the site is sheltered from strong winds to protect the structure.

IS A PERMIT REQUIRED TO BUILD A GREENHOUSE?

Generally, building a small to medium-sized greenhouse does NOT require a permit, but we recommend checking local regulations to confirm.

HOW CAN I PREVENT MY GREENHOUSE FROM OVERHEATING IN THE SUMMER?

Our polycarbonate greenhouses are designed with manual vents to promote adequate ventilation. We also offer automatic vent openers to help manage internal temperatures effectively during warmer months.

WHAT WARRANTY OPTIONS ARE AVAILABLE FOR YOUR GREENHOUSES?

Our greenhouses come with a comprehensive warranty—5 years for the frame and 3 years for the polycarbonate panels. For more details, please review our Terms & Conditions.

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Better Insulation & Plant Protection

Polycarbonate panels help retain heat while diffusing sunlight, reducing the risk of plant burn and creating a more stable internal temperature. This makes polycarbonate greenhouses a practical choice for growing vegetables, seedlings, and delicate plants in changing weather conditions.

Strong Aluminium Frame Construction

Each greenhouse is supported by a durable aluminium frame that is lightweight, corrosion-resistant, and built for long-term outdoor use. The combination of polycarbonate panels and aluminium framing creates a strong, low-maintenance structure suitable for everyday gardening. 

Ideal for Backyard & Home Growing

Whether you need a compact greenhouse for a smaller garden or a larger structure for more serious planting, this collection offers flexible options for a wide range of spaces. For additional growing support, explore our planting collection or browse greenhouse accessories to complete your setup.

Build a Complete Greenhouse Setup


A well-designed greenhouse works best when paired with the right tools and accessories. From irrigation systems to plant protection and internal organisation, the right setup helps improve plant health and makes daily gardening easier.

Explore More Greenhouse Options


If you are comparing different greenhouse materials and styles, you can also view our glasshouses for maximum light transmission or browse our full range of greenhouses in NZ to find the best option for your space.

Support Your Growing with the Right Tools


Complete your greenhouse setup with products from our planting collection, including watering systems, plant protection, and garden essentials designed to support healthy growth throughout the season.

Polycarbonate Greenhouses for New Zealand Gardens


Looking for more options? Browse our full range of greenhouses in NZ to compare different styles and sizes.