The new 8X12 Cedar Greenhouse from is highly insulated with 6mm twin-wall polycarbonate roof and side panels. Two automatic heat-activated vent openers are included to keep the greenhouse cool and well-ventilated on warm days. Shelving for both sides is also included. The 8X12 Cedar Greenhouse is designed for easy assembly with common tools and can be put together is just 2 or 3 days.