how do you measure an unbrella
How to Measure Patio Umbrellas: Patio Umbrella Size is determined in width ânotâ height. To find the correct measurements, measure the distance between the top of the rib arm and the bottom the rib arm. Then simply multiply that by two, which will give you the correct size.ow to Measure Patio Umbrellas: Patio Umbrella Size is determined in width ânotâ height. To find the correct measurements, measure the distance between the top of the rib arm and the bottom the rib arm. Then simply multiply that by two, which will give you the correct size.