Janssens Modern M36 Greenhouse 10 x 20

• The Janssens Royal Victorian Greenhouse reinterprets a classic architectural style for the modern garden. Rather than the boxy utility look of standard greenhouses, this model borrows from Victorian conservatory design — ridge cresting, a refined roofline, and full-height glazing — to create something that reads as a garden room as much as a growing space.
  
• The walls are built entirely from 4mm tempered safety glass, so there's no half-height paneling or opaque lower section breaking up the sightlines. It's a true all-glass structure from floor to eave, which matters both for light penetration and for how the greenhouse looks sitting in a yard.
  
• For anyone in a hot or high-UV climate, there's a hybrid configuration available: a 10mm heat-block polycarbonate roof paired with the same glass walls. The polycarbonate diffuses direct sun and cuts glare, which reduces the risk of scorching plants directly beneath the roofline while still keeping the glass walls for the aesthetic.
  
• Interior headroom is a deliberate design choice here — 6'7" sidewalls, taller than what's typical in this category. That extra height means less stooping near the perimeter and more usable vertical space for shelving, hanging baskets, or taller plants along the walls.
  
• Structurally, the frame is 17-gauge aluminum, chosen for a strength-to-weight ratio that holds up under wind and snow load without adding unnecessary bulk. Every seam where glass meets frame uses rubber glazing seals, and the windows are fully sealed — this is what keeps the structure quiet and draft-free rather than rattling in wind, which is a common complaint with lower-end glass greenhouses.
  
• Layout flexibility is built in too: the double sliding door isn't fixed to one wall. It can be installed on any side of the structure, which lets the owner orient the entrance based on their yard layout rather than being locked into the manufacturer's default.
  
• Finally, the unit ships with an integrated 6" foundation frame, meaning it's engineered to sit on a proper base or footer rather than being staked directly into soil — an important detail for anyone budgeting for the installation, since site prep needs to account for this.

Everything needed to enclose and operate the structure comes in the box:

• The complete frame system, glazing panels, and rubber seals for weatherproofing
• Roof vents with automatic wax-based openers and spindle mechanisms (the number of vents scales with the size ordered)
• One louver window with a Lexan panel for additional passive ventilation
• The double sliding door
• A built-in misting system for humidity and irrigation control
• Decorative Victorian ridge cresting along the roofline
• Gutters with downspouts for rainwater management

The Royal Victorian is offered in three footprints, so the right size really depends on available yard space and intended use:

VI 34 — the smallest of the three, measuring 10'2" wide by 15' long, giving 152 square feet of growing space. A good fit for tighter yards or buyers who want a dedicated glass structure without committing a large section of the property to it.

VI 36 — steps up to 10'2" wide by 19'11" long, totaling 203 square feet. The extra length adds meaningful room for benching, potting stations, or a wider variety of plants without changing the footprint's width.

VI 46 — the largest option at 12'7" wide by 19'11" long, offering 250 square feet. The added width here (rather than length) opens up the interior significantly, better suited to buyers who want room to walk around freely or set up multiple growing zones.

All three share the same 9'2" peak height and 6'7" sidewall height, so the difference between models is footprint, not headroom.

Build and materials

• Brand: Janssens, distributed by Exaco, manufactured in Belgium
• Frame: 17-gauge aluminum, available in Black or Dark Green
• Wall glazing: 4mm tempered glass throughout
• Roof glazing: choice of 10mm twin-wall polycarbonate or 4mm tempered glass
• Roof pitch: 22° or 25°, depending on model
• Foundation: integrated base frame, compatible with stem wall installation

Ventilation and access

• Roof vents: automatic wax-based openers or manual, sized at 29" x 33"
• Door: double sliding, 56.75" x 70.5"

Performance ratings

• Wind rating: 115–120 mph depending on size
• Snow tolerance: 20 psf roof live load, 25 psf ground-snow load
• R-value: 1.2–1.89 depending on glazing choice
• Rainwater collection: integrated gutters with downspouts on both sides

Other

• Expandable: no — this is a fixed-footprint structure, not modular
• Warranty: 15 years, limited

Assembly typically takes 2–3 days with a crew of 2–3 people — this isn't a same-afternoon build, largely due to the glass glazing work and the size of the larger models. Buyers should plan the timeline and labor accordingly, especially if they're coordinating with a foundation contractor beforehand.

• Manual

• Free shipping to all 48 contiguous states
• Delivery time: 8–13 business days
• Ships via LTL freight (curbside): liftgate drops the pallet at ground level; plan on 2–3 people to move it from the curb to your install site
• Outside the mainland US (Alaska, Hawaii, international)? Shipping terms need to be confirmed separately

The structure carries a 15-year limited warranty covering the frame and build.

Damages:

Please inspect the packaging of your item(s) when they arrive, if you notice any damage you should make note of it when signing for delivery.  If your item(s) do arrived damaged, please send photos to support@planetgreenhouses.com and we will process an insurance claim on your behalf.

Cancellations & Refunds:

All orders cancelled after 48 hours are subject to a $20 administration fee, whether or not your order has shipped.  If you order has shipped, you (the buyer) will also be responsible for actual return shipping charges. Refunds will only be issued to the original credit card that you use when placing your order.

Many of our items are heavy items and will not be able to be returned due to buyers remorse.  All sales will be final in this case.

If there is a part or piece missing, we ask the customer takes a photo of the shipped item and we will immediately try to have the missing part shipped if we have it in stock.  

in certain situations, we will accept an item to be returned when submitted to our RMA department.  The buyer will be responsible for full return shipping cost and a 25

25% restocking fee. This must be approved by our RMA department first.