The Fundamentals of Fiberglass - Fibre Glast Developments: "Worksheet For Estimating Materials
1) Begin by calculating the surface area of the project. Estimate irregular shapes by measuring the approximate sized rectangles necessary to contain the tapered areas. Multiply the length times the width for each rectangle, and then add all of individual rectangles together to get the total surface area of the part. If the calculation is in square feet, divide by 9 to get square yards.
2) Make a list of each type of reinforcement being considered for the lamination. Multiply the square yards calculated above times the ounce weight of the fabric. This is the total weight of one layer of that material. It is also the amount of resin required to saturate it. When this is known for two or three different types of materials, it is possible to calculate the weight and cost of a laminate constructed from any combination of these fabrics. To convert the ounce weight to pounds, divide by 16. Those inexperienced in saturating fiberglass tend to use far too much resin. A well saturated laminate is uniformly translucent, without milky appearing dry spots, but for the sake of weight and cost, has little excess resin in it."