How to Install a Replacement Vinyl Window in a House
- 1). Take measurements of the width and height for the opening, holding a tape measure along the inside tracks where the sashes are. Take the measurements from a few different points and use the smallest span in each direction. Order the new windows with those measurements. Don't remove the old windows until the new ones are delivered.
- 2). Take out the existing windows once the new window unit arrives by prying off the edge of wood trim holding them in, using a pry bar and hammer. Keep the trim intact as you remove it. Pull the window sashes into the room.
- 3). Set the new vinyl replacement window unit in the opening, setting the bottom in place first and then pushing in the top. The border of trim on the outside of the opening will stop the unit from falling all the way through.
- 4). Hold a level on the side of the unit and shim around it to get it level.
- 5). Drive mounting screws outward through the sides of the unit, using the screw holes there, to secure the unit to the surrounding frame.
- 6). Fill the gaps around the window unit with spray foam insulation.
- 7). Use your hammer and trim nails to reset the trim around the perimeter of the new window unit, hiding the gaps and holding in the window.
- 8). Caulk around the sides of the trim.
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