How to Buy Interlocking Roofing Shingles
- 1). Make a rough sketch of your roof divided in the different sections of the different slopes. You will need to measure the length, width and slope of each section, and add them up to find the square footage of your roof.
- 2). Prop your ladder up against your roof securely, and climb it. Measure each side of your roof according to your sketch, and write these measurements on your sketch.
- 3). Lay the level on one of the downward slopes of your roof. Lift the lower end of the level up until the level is straight (the bubble should be in the center). Measure the distance from the roof to the level. The number of inches is your slope. Find the slope measurement for each of the roof sections on your sketch.
- 4). Multiply the length, width and slope of each section to calculate your square footage. Add the square footage of each section together to find the total square footage of your roof. Add roughly 10 percent to the total for trimming and spoilage.This is how much roofing you will need to purchase.
- 5). Account for shingle damage and shingles needing to be cut by adding on an extra 1 percent or 5 percent to your square footage. If you have a simple roof you will just need multiply your calculated square footage by .01 and add this number to your calculated square footage. If you have a roof with many different slopes and levels, you will need to multiply your calculated square footage by .05 and add this number to your calculated square footage.
- 6). Locate a manufacturer that sells interlocking shingles by either calling local roofing companies or looking online. Some companies that sell interlocking roofing shingles are: Interlock, Sherriff-Goslin and New England Metal Roof.
- 7). Discuss and compromise on the pricing of your chosen shingles with the roofing company based on your square footage and slope calculations.