Janssens Modern Pent Roof Glass Greenhouse Kit With 4mm Tempered Glass Glazing - M23-MODERN

Janssens  Modern Pent Roof Glass Greenhouse Kit With 4mm Tempered Glass Glazing - M23-MODERN

The Janssens Modern Pent Roof Glass Greenhouse Kit features a sleek sloping roof design that matches the modern house style. Use this greenhouse as a perfect year round growing environment for your herbs, fruits, or veggies. Or use it as a relaxing lean to sunroom, a whimsical standalone backyard lounge, a cozy jacuzzi house to extend your living space beyond your house.

• 1 set of double hinged doors with closers
• 2 roof vents.  One with an automatic heat-operated opener (no electricity needed), one with a manual spindle opener.
• 2 louvered windows on M34/36.  1 louvered window on M23.  Louvered windows come with:
• Automatic heat-operated openers (no electricity needed)
• Clear Lexan winter cover for the cold season
• 2 push out / tilt windows

To support the longer roof glass panels of this unique glass greenhouse design, the aluminum roof rafter/profiles are twice as thick as our normal profiles. All standard units also include additional triangle cross supports.  The strong frame combines with the 4mm tempered safety glass construction make for a very durable, long lasting structure with little maintenance. an be added to further increase the roof strength.

This beautiful greenhouse is highly customizable by special order - size, glazing material, frame color, roof and wall features such as doors, panels, and windows. Call us at 888-648-5333 to arrange a free design session to configure your dream version!

• Basic colors: Black, Pure White, Fir Green
• Custom colors: Bronze, Anthracite (Dark Grey), and hundreds of other RAL colors.  
• 8x12.5 ft
• 8x15 ft
• 8x17.5 ft
• 8x20 ft
• 10x10 ft
• 10x12.5 ft
• 10x17.5 ft

Narrow glass panels (half the width of the standard panels) also available by custom order.

Ground mount is standard.  You can also select that you are building the greenhouse on a 16" or 24" wall (see exact dimensions in the manual) - the glass of the greenhouse wall will be shorter to maintain the same gutter height.  The door will extend to the grade level in a cutout in your wall.  You can also special order for an 8" wall - call 888-648-5333.

If you want to build the greenhouse on top of your wall with the normal full height glass to raise the whole greenhouse up), you will need a drop door kit to lower the door to the grade level, and you will need to provide your own piece of tempered glass to fit above the dropped door.  Be sure to let us know your wall height when ordering this way, so we can be sure the drop door kit is long enough.

A note about special orders: the pricing given on this page for special sizes and colors is an initial estimate for your information and comparison, all special and custom orders will require a price quote.  Your custom order will be built for you in the Janssens factory in Lier, Belgium, and your estimated arrival for your unique build will typically be 14-16 weeks, depending on the factory queue and the shipping pipeline, and other factors beyond our control.  Call us at 888-648-5333 or email info@MyGreenhouseStore.com for more information.

If you prefer to have a professional crew assemble and install the greenhouse for you, call 888-648-5333 for some recommendations from our list of experienced builders.

FEATURES

• Color: Black. Other colors available by custom order - call 888-648-5333 to discuss.
• Frame Material: Aluminum
• Spacious hobby greenhouse.
• Strong aluminum frame construction with thick gauge
  
• Aluminum roof rafter/profiles are twice as thick as our normal profiles
• Rafter Inserts can be added to both the center and end roof profiles, for additional strength and rafter stiffness
• Roof and sides are 4mm tempered glass glazing for safety and good insulation value. Glass is secured in place with heavy rubber sealing. 
• Optional 10mm twin-wall polycarbonate roof or both the roof and sides (instead of glass) is available as a custom order.
• 1 set of double hinged doors with closers
• 2 roof vents, one with automatic heat-operated opener (no electricity needed), one with manual spindle opener

SPECIFICATIONS 

• M23: 7ft 9in wide
• 10ft 2in long (other lengths by custom order)
• 75 sq ft
• Sidewall height (low side): 6ft 6in
• Sidewall height (high side): 8ft 10in
• M34/M36: 10ft 2in wide 
• 15ft (M34) or 19ft 10in (M36) Long (other lengths by custom order)
• Sidewall height (low side): 6ft 8in
• Sidewall height (high side): 9ft 7in
• Double hinged door: 56.75x70.5 in
• Frame Material: Aluminum
• Color: Black (other colors by custom order)
• Glazing: 4mm Tempered Glass
  

What Our Experts Think

• Modern Pent Roof Design: Clean, contemporary styling that blends seamlessly into modern gardens while maximizing natural light exposure.
• Efficient Growing Layout: The pent roof structure provides excellent headroom and usable space for a variety of plant types and shelving setups.
• 4mm Tempered Glass Glazing: High-quality glass ensures strong light transmission, durability, and long-term weather resistance.
• Year-Round Growing Performance: Helps maintain a stable internal environment for consistent plant health and extended growing seasons.
• Strong Aluminium Frame Construction: Engineered for outdoor durability with corrosion resistance and reliable structural support.
• Low-Maintenance Premium Build: Designed for long-term use with minimal upkeep while maintaining a professional greenhouse appearance.

Q&A

Maintenance Tips

• Clean tempered glass panels regularly with a soft cloth and non-abrasive glass cleaner to maintain clarity and maximum light transmission.
• Inspect glazing seals, clips, and rubber gaskets periodically to ensure all panels remain secure and weather-tight.
• Remove dirt, algae, and organic buildup from the frame and base to prevent corrosion and staining.
• Check doors, vents, and roof sections seasonally and lubricate hinges and moving parts for smooth operation.
• Ensure proper drainage around the greenhouse base to prevent water pooling and structural stress.
• Tighten bolts and structural fittings regularly, especially after strong winds or seasonal changes.
• Keep ventilation systems clean and fully functional to maintain stable temperature and humidity levels.
• Inspect the aluminum frame for scratches or corrosion and treat exposed areas promptly.