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Grandio Summit 12×28
Original price was: $9,499.00 – $11,924.00Price range: $9,499.00 through $11,924.00. Price range: $8,499.00 through $10,924.00Current price is: $8,499.00 – $10,924.00Price range: $8,499.00 through $10,924.00.
FREE SHIPPING! Status: Winter Restock – Ships December 2025 Perfect timing for spring greenhouse setup!
Welcome to the Grandio Summit 12×28
Actual Size: 12′ W x 28′ L x 9.25′ H
This beautiful barn-style greenhouse delivers year-round growing space with a heavy-duty aluminum frame and premium 10mm twin-wall polycarbonate panels. Your Summit greenhouse comes equipped with professional-grade features including 10mm twin-wall panels, a heavy-duty powder-coated aluminum frame, impressive 9.25′ tall roof height, re-engineered sliding double doors with lockable handles, (14) roof windows with ample ventilation, rain gutters, drain kit, extreme snow load kit, flat mount anchor kit, and comprehensive long-term warranties.
Premium Accessory Package Adds ($1224 Value):
- (14) Auto Roof Window Openers
- (2) Packs of 10 Plant Hangers
- (2) 8 oz. Brillianize Cleaner
- (1) Trellis Kit
- (1) Drip Kit
Engineered to perform in harsh environments, the Grandio Summit’s rugged durability makes it one of the most insulated greenhouses on the market. Its barn-style design is both elegant and functional, maximizing growing space while creating an attractive addition to your property. Built to meet the highest standards of hobby and professional gardeners alike, the robust 1.6mm aluminum frame profile provides superior strength and durability compared to competitors.
The Summit’s extensive feature set creates a well-ventilated growing space with ample roof windows and re-engineered sliding double doors. The UV-protected 10mm paneling delivers an impressive (R) value of 1.89* and heat loss (U) value of 0.53, providing optimal insulation in all climates. The doors hang from above to eliminate jamming, featuring high-quality nylon wheels and precision-turned solid brass bolts with smooth shanks to reduce wear. Heavy-duty lockable door handles with included key provide security and peace of mind.
Carefully engineered to the highest standards, gardeners of all types will appreciate the combination of strength, quality, performance, and value that Grandio Greenhouses are known for. Reach the Summit with Grandio!
Foundation & Anchoring Solutions
Concrete Slab or Wood Deck Installation: Installing on a concrete slab or wooden surface? The included Flat Mount Anchor Kit provides solid footing with your choice of fasteners for concrete or wood surfaces.
In-earth Installation: Planning to install your Grandio Summit directly into the earth? We highly recommend our Steel Base Kit with Earth L-Bolt Anchor Kit. This powder-coated steel system resists rust and corrosion, designed to be buried into the ground or backfilled with gravel for a solid foundation that combats wind and extreme environments. Simply select “Base Kit (Earth L-Bolt Anchor Kit)” at checkout for everything you need.
Unmatched Warranty Protection
Our lifetime frame warranty and 10-year panel warranty represent more than peace of mind – they’re our commitment to exceptional quality, dependability, and reliability. Every Grandio Greenhouse is precision-manufactured to meet rigorous standards and engineered to withstand extreme wind and weather conditions.
*R-Value – measures the ‘insulating ability’ of materials. Higher R-Value = superior insulation performance.
*U-Value – measures ‘heat loss’ through materials. Lower U-Value = less heat escape.
| Attributes | Value |
|---|---|
| Choose Package (Basic or Premium) |
Basic, Premium |
| Brand |
Grandio Greenhouses |
Technical details for those who need more.
- Height: 9′ 3″
- Width: 12′
- Length: 28′
- Frame: Heavy duty aluminum.
- Wind Rating: Withstands winds up to 76 mph*
- Snow Rating: Maximum snow load of 25lbs./ft² of snow*
- Color: Powder coated green.
- Panels: 10mm twin-wall UV protected polycarbonate.
- Door Size: 41.5″ W x 85″ H
- Doors: Bind-resistant sliding double-doors.
- Latch: Magnetic latch doors with key lock.
- Reinforcement: Cross-roof truss and cross corner bracing.
- Tools: Included
- Hardware: Stainless steel nuts and bolts.
- Gutters: Built-in rain gutters.
- Ventilation: (14) roof vent with adjustable manual openers/latches
* Please see the warranty page for further details
Looking for assembly instructions? Find them here.
This is your resource for finding complete assembly instructions for all Grandio Summit Greenhouses. You can download the instructions in PDF format or you can view the assembly video. We’ve provided everything you need to get started with your new Grandio greenhouse. Have questions? Give us a call 1-866-448-8231.
Grandio Summit Greenhouse Assembly Manuals
» Download: Grandio Summit Manual 1 – Base Kit Assembly Instructions and Installation
» Download: Grandio Summit Manual 2 – Summit Greenhouse Assembly Instructions
» Download: Grandio Summit Manual 3 – Itemized Parts List, Graphics, Descriptions and Quantities
Grandio Summit Greenhouse Anchoring Kit Manuals
» Download: Grandio Summit Manual 1 – Flat and Earth Base Kit Assembly with Earth Anchoring Kit
» Download: Grandio Summit Wood Anchoring Kit Supplement Manual
» Download: Grandio Summit Concrete Anchoring Kit Supplement Manual
Note: In order to read the manuals, you need the Adobe Acrobat PDF reader.
You have questions, no problem, we have answers.
How easy is the Grandio to assemble? Very easy. We’ve designed and perfected the assembly process with you in mind. We provide the tools and a step-by-step assembly manual and video and if you have any problems you can call us at 1-866-448-8231.
Is a building permit required? You may not need a permit for your Grandio, but it is always a good idea check before you get started. We recommend you check local ordinances and requirements before setting up your greenhouse.
Is it strong enough for windy or heavy snow locations? Definitely. Grandio’s are all designed to withstand the most hostile environments with a wind rating of 76 MPH and snow load rating of 25lbs./ft² of snow. We offer additional roof and eave supports to increase the strength and durability of the greenhouse frame for the Element Greenhouses. Just follow the included directions for securing your greenhouse and you’ll enjoy many years of growing with your Grandio.
I live in the hot southwest will Grandio Greenhouses work for me? For people who live in high temperature areas of the country like Arizona, Texas, California, Nevada, or New Mexico we recommend our aluminum shade net. The aluminum shade net reflects the sun on the hottest days to help your greenhouse keep it’s cool.
How do the automatic roof vent openers work? The opener has a metal cylinder containing a mineral which expands when heated. This pushes a piston that opens the vent. As the temperature cools, the mineral shrinks and a spring closes the vent and resets the piston. The opening and closing of the vent is gradual allowing just the right amount of air flow for cooling. No electricity needed!
How large is the roof vent opening? The vent opening is 18-3/4″ width by 22-3/4” length.
What is the difference in polycarbonate thicknesses? Polycarbonate is available in several different thicknesses and normally comes in single, double, and triple walled sheets that can vary in thickness from 1mm to 10mm. A good rule to remember is that the thicker the panel the better insulation you’ll have for your greenhouse.
Can these greenhouse be mounted to a concrete pad? The Grandio comes standard with a base that is meant to anchor it in the soil with concrete footers or a duckbill anchor kit. However, it can be mounted to a concrete pad with additional tools and hardware. For more information please refer to our online manual or give us a call 1-866-448-8231 to discuss options.
Can’t wait for your Grandio? Here’s what to expect.
How many boxes will I receive?
Your new Grandio ships in 2 or more manageable-sized boxes (the exact number of boxes depends on the size of your greenhouse).
How is it shipped?
Grandio Greenhouses are generally shipped via UPS Ground.
Can I buy a Grandio if I live outside the USA?
Currently we can only ship orders to the USA and Canada. If you live in Canada and would like to place an order please call us at 1-866-448-8231.
How long will my order take to get to me?
-
- West: 2-4 business days
- Northwest: 1-3 business days
- Southwest: 3-5 business days
- Midwest: 4-6 business days
- East: 5-7 business days
Note: These are estimates and business days are the time your items are in-transit only and do not include order processing time. Inclement weather and unforeseen carrier or transportation emergencies may delay your delivery.
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