What is a window buck?

Thursday, October 3, 2019

During construction of a building, builders must leave openings in the walls for the later installation of windows. These openings are lined with frames called bucks. Wood is the material traditionally used to build bucks. A wood buck on a window is a wood frame that was set into the wall to define the space for window installation.

Constructing a Wood Buck

You can make a wood buck in three ways, according to ICF Builder Magazine. The first, and most common, option is the external buck. The ends of the buck are placed flush with both faces of the wall using a frame of 1 by 4s attached to both sides of the buck to fasten the buck to the wall. The second option is an internal buck cut to the width of the opening in the wall and secured with long drywall screws. The third option is a combination of the first two.

Window Buck, Impact Windows. Pressure Treated Window
Pressure Treated Wood Buck

Bucks in Concrete

Wood bucks installed in concrete walls or bucks that might touch concrete need to be made from pressure-treated wood or separated from the concrete by a waterproof material.


ICF Builder Magazine offers the following tips for building bucks. Use hot-dipped galvanized nails as fasteners because the lumber might corrode other fasteners. Hammer the nails to the outside of the buck about every three inches. If the window opening is larger than three feet either horizontally or vertically, prevent bowing by bracing the buck every two feet. If the buck is large, help lift and position the sill on the wall by fastening blocks to the sill.

If you got lost along the way or just have more questions on what a window buck is, don’t hesitate to give us a call at (561) 420-0271. We are here to help, Impact Windows and installing them are what we do.