Just a warning, the price of greenhouse glass has shot up over the last couple of years. A piece 24x24" which is the normal size we retail for £15.49, you can add another pound or two for cutting to make the triangular bits. The 24"x18" retail for £10. 49 but if y ou need what's known as a Dutch Light (56"x28 and three quarter inches, sorry that button doesn't work on the keyboard) will cost you a whopping £46.95. We've just changed our supplier of glass as the Company we used to use stopped making greenhouse quality glass and they were even more expensive.