Grandio Summit 12×28 ft Polycarbonate Greenhouse – Premium Barn-Style Growing Space

Overview

Create the ultimate year-round growing environment with the Grandio Summit 12×28 ft Polycarbonate Greenhouse. Built with a heavy-duty 1.6mm powder-coated aluminum frame, 10mm twin-wall insulated polycarbonate panels, and a 9.25 ft barn-style peak height, this premium greenhouse delivers exceptional durability, weather resistance, and growing performance in any climate.

Engineered for hobbyists and professional gardeners alike, the Summit offers outstanding insulation, excellent ventilation, and industry-leading strength—making it one of the most rugged and elegant greenhouses available today.

✔️ Key Features

• Heavy-duty 1.6mm powder-coated aluminum frame

• 10mm UV-protected twin-wall polycarbonate panels

• High 9.25 ft peak height for maximum interior space

• R-Value 1.89* / U-Value 0.53 for superior insulation

• Withstands winds up to 76 mph

• Supports 25 lbs/ft² snow load

• (14) roof vents for excellent airflow

• Re-engineered sliding double doors with lockable handles

• Integrated rain gutter system included

• Lifetime frame warranty + 10-year panel warranty

• Total growing area: 288 sq. ft.

Premium Accessory Package ($1224 Value) – Upgrade Option

Enhance your greenhouse with automation, organization, and convenience.

Includes:

• (14) Automatic Roof Vent Openers

• (2) Packs of 10 Plant Hangers

• (2) Bottles of Brillianize Panel Cleaner (8 oz.)

• (1) Trellis Kit

• (1) Drip Irrigation Kit

What’s Included

Basic Kit

• 10mm Twin-Wall Polycarbonate Panels

• (14) Roof Windows

• Integrated Rain Gutters

Premium Kit

Everything in the Basic Kit, plus:

• Drain Kit

• Extreme Snow Load Kit

• Flat Mount Anchor Kit

• (12) Auto Roof Window Openers

• (1) Drip Kit

• (1) Trellis Kit

• (1) Pack of 10 Plant Hangers

• (1) 8 oz. Brillianize Cleaner

Specifications

• Dimensions: 12′ W × 28′ L × 9.25′ H

• Assembled Size: 144" W × 284 3/16" L × 95" H

• Frame Material: 1.6mm aluminum

• Color: Powder-coated green

• Panels: 10mm UV-protected polycarbonate

• Wind Rating: 76 mph

• Snow Load: 25 lbs/ft²

• Door Size: 41.5" W × 85" H

• People Required: 2

• Assembly Time: 1 weekend

• Total Area: 288 sq. ft.

• Base Required: No

• Shipping: LTL, 2+ manageable boxes

Foundation & Anchoring Options

Concrete Slab / Wood Deck Installation

The included Flat Mount Anchor Kit secures your greenhouse to a concrete or wooden foundation.

In-Earth Installation (Recommended for Windy Areas)

Choose the Steel Base Kit with Earth L-Bolt Anchors for maximum ground stability, corrosion resistance, and long-term durability.

Select “Base Kit (Earth L-Bolt Anchor Kit)” at checkout.

Optional: Back Door Transformation Kit

Add a second entry point + increase cross-ventilation for summer growing.
Perfect for hotter climates or high-traffic greenhouse layouts.

Insulation Performance

• R-Value: 1.54–1.89

• U-Value: 0.53–0.65

Higher R-Value = better insulation
Lower U-Value = less heat loss

The Grandio Summit Advantage

Designed for harsh environments and year-round gardening, the Grandio Summit offers unmatched strength, premium materials, and an elegant barn-style profile that enhances any property.

Grow more. Grow longer. Grow better.