Measuring a Home for New Insulated Vinyl Siding

August 4, 2018



Simple math, a few tricks, and a couple of rules of thumb make a pretty good checklist


Properly measuring a home for new siding is critical in quoting a job. Our checklist is a helpful tool to have. This video is intended to help provide basic instruction and some added tips and tricks. 

  • Starting with the square and rectangular walls, measure the height and width. Siding is ordered squares, and one square equals a hundred square feet. Multiply the height and width and then divide by a hundred to calculate how many squares are needed. 
  • If using different materials on different walls, make sure to keep those separate.
  • Do not subtract the window area—unless it's a very large picture window—but subtract the garage door area. 
  • For gables, measure the height and width, and multiply by .75. If a gable is hard to reach, a quick trick is to measure the height of the current siding profile, then multiply by the number of courses on that wall section. For instance, if the siding height is ten inches and there are 12 courses, the wall is ten feet tall.
  • For dormers, multiply (width x height) x (1.5). This allows enough material for both sides. 


Accessory measuring advice

  • Avoid seams in corner posts whenever possible.
  • Count the number of inside and outside corner posts, order one post per corner. If the corner is taller than the post, buy extra.
  • For starter strip and starter adapters, measure the base of all walls. 
  • Where siding meets brick, use Z flashing.
  • Where siding meets a deck, use j-channel instead of starter strip
  • For all other j-channel, plan on two pieces per window and one and a half pieces per door. That will help prevent seams around the openings.
  • Use j-channel where siding meets a soffit.


—This video is from Progressive Foam Technologies, one of ProTradeCraft's advertisers. Founded in 1992, Progressive Foam invented and brought insulated vinyl siding to the marketplace and have since diversified to add siding insulation products that can be paired with fiber cement, engineered wood, steel, and others. See all of Progressive Foam Technology's videos.