Riga IV German Hobby Greenhouse with two shelves and base (9 ft. 8 in. W x 14 ft. L x 7 ft. 1 in. H; 135 sq. ft.) Purchasing a premium quality greenhouse is an investment. With the Riga IV you get premium materials as well as premium customer service. Exaco Customer Service can be reached 7 days a week and have been trained for the Riga series of greenhouses; there is no question they can't answer. If you have questions give them a call at 877-760-8500. The Riga IV frame is made from 12-Gauge aircraft aluminum and is designed to last a lifetime. The framing is assembled with all stainless steel hardware and carries a 15-year warranty. The Riga IV is covered with UV coated Twin-wall Polycarbonate Glazing. The polycarbonate is 10 mm thick on the front and rear and 8 mm on the sides. This along with the precise construction gives the Riga IV best insulation in its category. Adding a small heater in the winter will keep the Riga IV warm throughout the season. The unique design of Riga IV not only looks good on your property, but has many benefits too. The sloped roof prevents snow buildup; it just slides right off. This design also allows strong winds to blow right over and hail bounces harmlessly away. The Riga IV is outfitted with a 30 in. W Dutch style door in the front, an oversized roof window and an oversized window in the rear wall. No matter what level of gardener you are the Riga IV will make you feel like a professional.