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Grandio Summit 12X8 Aluminum Greenhouse

List Price: $3899.00
Our Price: $3199.00
Available Options:
Anchor Kit:
Automatic Louver Window Opener:
Automatic Roof Vent Opener:
Drain Kit:
Drip Irrigation Watering Kit:
Extra Door:
Louver Window:
Moisture Control Kit:
Plant Hangers:
Shade Net:
Quantity Availability: In Stock

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*We can not price match local stores, warehouses, price clubs, or prior sales and the item must be new and in stock. Please see our guarantee for more details.

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Due to extraordinary circumstances, all Grandio greenhouses may take up to 6 weeks to ship, though it may be a bit sooner.

As an authorized dealer, we're accepting orders and are in constant contact with Grandio to ensure that your receive your greenhouse in a timely manner. Please let us know if you have any questions at all.

Shipping included for the contiguous United StatesThe Grandio Summit 12X8 Greenhouse is a wonderful addition for gardeners off all experience levels. It features a tall barn-shaped roof with a peak height over 9 feet tall to give you plenty of growing room for even your tallest plants.

10 Year Limited WarrantyThe Summit has been designed for durability as the frame is made of high quality extruded aluminum and a snow load kit is included to further strengthen the roof. The powder-coated green frame fits well in any setting, and the greenhouse comes with an industry-leading 10 year limited warranty on the panels and a limited lifetime warranty on the frame.

Grandio GreenhousesThe panels are of the highest quality as well, as the Summit includes 10mm twin-wall polycarbonate wall and roof panels that are both UV-stablilized and impact resistant. These provide significantly more insulation than the typical 4mm or single-wall panels found on other units.

The Summit is designed to be assembled in only a weekend or less depending on how much help you have with just common household tools. The kit includes items that are optional on other greenhouses like the snow load kit and and rain gutters on both sides, and the greenhouse can be easily expanded in 4 foot increments to meet all your future growing needs.


  • Model: SUMMIT-128
  • UPC: 859248005670
  • Nominal dimensions: 12' 0" width x 8' 1 1/4" length x 9' 6 1/4" peak height
  • Side wall height: 61 1/4"
  • Color: green
  • Frame is made of strong extruded aluminum (1.6 mm profile) that is powder-coated
  • 10mm twin-wall polycarbonate panels are UV-stabilized, impact-resistant, and give great insulation for low operating cost
  • Panels have R-Value of 1.89 and heat loss U-Value of 0.53
  • High-quality sliding double doors for easy access with large 41.5" x 85" opening
  • Doors include a magnetic catch with heavy duty lockable door handles with key
  • Doors have durable nylon wheels and hang from above to prevent jamming
  • Tall internal height for added growing space
  • 4 adjustable roof vents with manual openers that open at 70 degrees to prevent overheating: 22" x 20"
  • Integrated rain water system with 1.75" gutters on both sides
  • Fully expandable in 4' increments
  • Includes flat-mount base kit for use when installing on wood or concrete foundation
  • Designed for easy assembly in just a weekend or less with common household tools and all parts are pre-cut and pre-drilled
  • All the necessary stainless steel nuts and bolts are included
  • Frame includes extra supports for added snow and wind load capacity
  • Includes clear and fully-illustrated step-by-step instructions
  • Elegant design to fit any garden
  • Perfect for growing in all climates
  • Note: Please be sure to check your local building code for any required permits and issues pertaining to zoning, setbacks, or restrictive covenants
  • Note: Some images may not be to scale or may show building with optional contents or accessories such as windows or shelving
  • Friendly technical support from Grandio Greenhouses available for installation help
  • Greenhouse Nation is an authorized dealer of all Grandio Greenhouse products
  • Grandio Greenhouses and Greenhouse Nation stand by its greenhouses and work to make you 100% satisfied
  • Ships direct from Grandio warehouse in Boise, Idaho within days
  • 10 year limited panel warranty and lifetime frame warranty

Grandio 12X8 Summit Flat Mount Base Dimensions

Grandio 12X8 Summit Steel Mount Base Dimensions

Grandio Greenhouse Polycarbonate Panel Comparison

Optional Accessories

Anchor Kit - This Grandio greenhouse includes a flat-mount base kit for use when installing on wood or concrete foundation. A concrete anchor kit or wood deck anchor kit is included at no additional cost. The optional steel base kit that includes earth L-bolt anchors is needed for customers who plan on anchoring their greenhouse directly over soil. Any of these base options will help keep your greenhouse secure in severe weather when properly installed and anchored.

Grandio Automatic Louver Window OpenerAutomatic Louver Vent Opener - The metal cylinder in the opener responds to an increase in outside temperature by automatically and gradually opening the louver window. As the temperature cools, a spring closes the vent or window and resets the piston. Automatic openers are extremely convenient for maintaining the proper greenhouse temperature and preventing your plants from getting overheated on hot summer days. The automatic openers from Grandio are designed for simple installation.

Grandio Automatic Roof Vent OpenerAutomatic Roof Vent Opener - The metal cylinder in the opener responds to an increase in outside temperature by automatically and gradually opening the roof vent. As the temperature cools, a spring closes the vent or window and resets the piston. Automatic openers are extremely convenient for maintaining the proper greenhouse temperature and preventing your plants from getting overheated on hot summer days. The automatic openers from Grandio are designed for simple installation.

Grandio Drain KitDrain Kit - The drain kit down spout installs directly into the frame and gutter of your Grandio greenhouse. It includes four 20mm black pipes, four gutter attachment gaskets, and four side wall brackets with screws.

Grandio Drip Irrigation Watering KitDrip Irrigation Watering Kit - The drip kit helps to keep your plants hydrated with minimal water waste and is perfect for a wide variety of plants. This kit can cover up to 150 square feet and includes 20 drippers at 1 GPH (gallons per hour), 2 drippers at 2 GPH, and 2 drippers at 4 GPH. A backflow preventer is included to stop water from being siphoned back into the main water supply, and the kit is designed for easy do-it-yourself installation.

Grandio Summit greenhouse doorExtra Door - An extra set of sliding double doors can be added to back of the greenhouse to provide access from both ends and complete cross ventilation for your greenhouse. These doors are the same as the same front doors with a large 41.5" by 85" opening.

Grandio Louver WindowLouver Window - The elegant louver windows add additional ventilation to the sides of your greenhouse. Each window has 6mm polycarbonate panels and can be paired with an optional automatic louver window opener for hassle-free operation on hot days when opening windows and vents is important.

Moisture Control KitMoisture Control Kit - The moisture contol kit includes multiple units of waterproof all weather silicone caulk and a specialized anti-dust tape to completely seal your greenhouse. The anti-dust tape has a fungicidal coating and 45 micron filters that allow condensation to escape the flutes of the polycarbonate panels. The kit provides waterproofing and will help prevent dirt, mold, algae, and insects from entering the channels of the polycarbonate panels.

Plant HangersPlant Hangers - These clips come in packs of ten and attach easily to any Grandio greenhouse, allowing baskets or pots to be easily hung from the ceiling. Hanging baskets are a great way to maximize your growing space.

Shade NetShade Net - The Grandio Summit Greenhouse Shade Net (21X9) is designed specifically for this Grandio greenhouse. The aluminum cover reduces the sunlight by 50% to help keep your greenhouse a comfortable temperature during hotter times of the year, especially the summer months.

Grandio Greenhouse Product Videos

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About Grandio Greenhouses

Grandio GreenhousesThe founders of Grandio Greenhouses have applied their combined decades of experience in the greenhouse space to a new line of greenhouses and accessories that are now among the most popular in the market. Grandio manufactures virtually everything needed by hobby and commercial gardeners alike and is popular with both.

Designed and engineered in Boise, ID, Grandio has a dedicated domestic support staff and an on-site R&D department. Superior customer service is a cornerstone of their business model along with fair pricing and an industry-leading product warranty.

Grandio offers a wide variety of accessories for its greenhouses that include shelving, shade cloths, and extra doors, and new products are constantly under development. Grandio's friendly staff is available to assist directly with any questions and the great pride taken in their product line is evident at every turn.

Manuals: Grandio Summit Greenhouse Base Installation Manual [50,567 k] 
Manuals: Grandio Summit Greenhouse Assembly Manual [24,872 k] 
Manuals: Grandio Summit Greenhouse Parts List Manual [4,174 k] 
Manuals: Grandio Summit Greenhouse Concrete Anchoring Kit Manual [1,225 k] 
Manuals: Grandio Summit Greenhouse Wood Anchoring Kit [883 k] 
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