How to Measure Vinyl Siding Replacement Dimensions

Choose a side to begin measuring and draw a "1" on it. This represents your starting point. Continue numbering all the sides of your house in sequential order. Write down all the numbers you drew on the sides of your house on a piece of paper. Next to each number you write on the paper, you will write the dimensions of the side of your house which correspond with that number to avoid confusion.

Measure the width of each side from margin to margin, and label the measurement "W" on your paper next to each number.

Measure the height of each side from where your siding begins to where your siding meets the bottom of your eaves --- the edges of your roof. Use a ladder, and have someone hold the measuring device down for you while you measure.

Multiply each width and height. Write down the result on your paper. This gives you the area in square feet of each side of your house. Add up the numbers and write down the total measurement.

Measure the height of each triangular part of the house and divide the results in half. Measure the width and multiply it by half the height. Add all the figures together, and add the result to your previous total.

Measure the width and height of all your windows and doors. Multiply the width and height of each to get the area in square feet. Subtract the total of all the areas of your windows and doors from your final total. Get approximately 30 square feet of vinyl siding above the number you ended up with.