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For homeowners & contractors
Measuring windows and doors
Finding the right measurement for your window or door can vary depending on what you intend to install. Certain window models allow replacement of the sash. Other windows require removing the entire window frame or installing a replacement window inside the old window opening. Doors almost always require the removal of the entire door and door frame. Rot at the bottom of your window or door jamb suggest it's time for an upgrade. Further damage can occur the longer you wait to replace them similar to a dental cavity.
If you plan on replacing your entire window system you'll need a "new construction window". This requires removing and replacing the interior/exterior trim molding and exposing the rough opening. The rough opening is the framing that constructs your window opening. You can generally find the rough opening by measuring the interior jamb and thereafter adding the correct sum. Interior jambs are typically 3/4"-1" thick on each side. There's usually 1/4"-1" of space on each side of the window unit. Determine the smallest measurement of the window jamb by measuring 3 locations for the width and height. If Jw=30" add 1.5" for the total size of the jamb thickness and 1.5" for the assumed space in between the window unit and the rough opening. The assumed rough opening is 33"x43". New construction windows may require exterior siding integration.
Newer model windows may have a small etching in the glass that can identify the exact window. From the etching you can determine from the manufacturer the exact window dimension and receive a schematic. Look carefully at the corners of the glass for a brand and model type. Inquire with the manufacturer for a replacement. The manufacturer may also require a measurement of the window pane.
Replacement windows can save money and time providing your openings are in reasonably good shape. These window units sit inside of existing window frames after the old window sashes are removed. Typically exterior trim can be undisturbed. Inside trim modifications are typical. Find the measurements of the inside jambs. Measure the width and the height at three different locations to find the smaller number. Provide jw(30)xjh40 as a primary figure. Make sure to examine the existing windows. Some older window units may require a different measurement or extensions.
Determining the right measurement for door replacements is a lot like measuring for new construction windows. The old door and frame are removed exposing the rough opening of the door. The new unit is placed inside. Determine the size of the actual door slab and add 2 1/4" inches to the height and width. This should determine the approximate rough opening. Rough openings are traditionally used to determine which door to order. If your spending a larger sum of money on a door it might be a good idea to remove the interior trim and obtain the measurement directly from the rough opening. If you measure the interior of the door jambs to find the rough opening remember that door jambs can be thicker then window trim. Doors sit on the plywood underneath your floor coverings. Depending on your floor covering this could be up to 1" thick. If you measure directly from the floor covering you may get a poor measurement.
written by Robert on 4/29/21
published by RMestimates
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