specifications. If your vehicle was originally charged with R12 refrigerant, for example, the oil type specified, 'mineral', will not apply. Additionally, General Motors issues Bulletin # 02-01-39-004B replacing PAG 150 oil with a lower viscocity oil.
The term square in reference to roofing materials refers to 100 square feet of roof area. One square of slate is the amount of slate that it takes to cover 100 square feet of roof area. A 10 foot x 10 foot section of roof would equal one square. So would a 4 foot x 25 foot section. Ditto for a 5 foot x 20 foot.
According to the 2014 US Census, the average square footage of the average American roof is 1700 square feet. Calculating the cost of a metal roof isn't as simple as just knowing your square footage, however. The price of metal is subject to fluctuation. Sometimes it can be pretty volatile.