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Activity no: 10-06588 Describe the reason for the proposed alternative: We would like to use corrugated polycarbonate (100%on greenhouse roof) for several reasons: 1. Corrugated polycarbonate lets approximately 90%light—close to what glass would be. 2. Polycarbonate is much lighter than glass, which means it requires less substantial framing. 3. The impact resistance is superior to glass—it will not break like glass, which would reduce the risk to our customers. 4. In glass greenhouses, there is the need for many smaller,overlapping glass segments that increase the risk of heat leakage. 5. Its rated class CC 1 (Section 2606 of the building code). Describe the why,how,etc., the proposed alternative is equivalent and meets the intent of the code in terms of"strength, effectiveness,fire resistance, durability, health, and safety". With the attached data sheet, you can see that corrugated polycarbonate is within the code guidelines for strength,effectiveness,and durability;however,there have been some questions about the fire resistance of the material and thus the health and safety of our patrons. We believe that the intent of the code is to ensure that no building is constructed of materials that may cause a fire hazard. We have included information on polycarbonate and have talked with the Woodburn Fire Marshall Paul Iverson. Both of these sources indicate that corrugated polycarbonate is not a fire hazard. The attached documents show the flammability rating of the material, which demonstrates that polycarbonate is a self- extinguishing material,and thus will not burn on its own. When we take into account that the structure is a retail greenhouse and will be filled with live plant material that is noncombustible and the framework of the greenhouse is steel we can see that there will be nothing in the greenhouse that would fuel any fire that happens to ignite. Therefore,if a fire were to ignite from an outside source it would extinguish immediately. While the proposed structure is approximately 6000 sft, one has to take into account that there are 6 exterior exits. Each 40X55 greenhouse will have exit doors on each end, which would mean a travel distance of less than 50 ft to exit the building in case of emergency. I believe that corrugated polycarbonate on the roof of a greenhouse is not a fire hazard and maintains the health and safety of our patrons and thus meets the intent of the building code.