How Are Replacement Windows Installed

When Maddy Krauss and her married man, Paul Friedberg, offset laid eyes on their 1897 Shingle-way home, they brutal in love with its handcrafted turn-of-the-century construction, wide front porch, and massive entry-hall staircase. They were also delighted to find that many of the original architectural details were still intact, including forest paneling, exquisite carvings, stained-glass windows, and an ornate cast-bronze fireplace.

The windows were another story. The originals had been swapped out a decade earlier for low-quality sash kits that were drafty, ugly, and completely inappropriate for the svelte Victorian-era home, This Old House TV'south fall 2007 project in Newton, Massachusetts. The solution: Call in TOH general contractor Tom Silva and his crew to install free energy-efficient replacements.

Because the existing window frames were audio and foursquare, Tom could use insert replacement units—in this example, Andersen's Woodwright Insert Replacement Windows, vinyl-clad wood units fitted with free energy-saving, low-due east insulated glass. These fully assembled, ready-to-install windows slip correct into the existing openings.

When the chore was done, the house had beautiful new double-hungs that looked right, worked smoothly, and gave Maddy and Paul 1 more than thing to honey about their old house. Here's a look at how Tom made the switch, with tips for choosing and installing replacement windows.

How to Install Replacement Windows

1. Window Replacement Parts

Types of Replacement Windows

Dissimilar full-frame windows, which are designed for new construction, replacement windows are fabricated to fit into existing window openings. They're bachelor in dozens of standard sizes, from every bit narrow as 11 ½ inches to as broad as 68 inches, and come in woods, vinyl, fiberglass, vinyl-clad wood, and aluminum-clad wood.

There are three bones types of replacement windows: sash kits, insert replacements, and full-frame units. Sash-replacement kits—what Tom found on the Newton house—give an old window frame new movable parts, including jamb liners and sash. The liners are fastened to the side jambs of the window opening, then the sash are slipped in between.

For these to piece of work, the existing window frame must be level and square. An insert replacement window consists of a fully assembled window in a set-to-install secondary frame. Sometimes called a pocket window, an insert replacement slips into the existing opening and is and then fastened to the onetime side jambs. Because you're adding new jambs and liners, the glass area will be slightly smaller than it was before.

Total-frame replacement windows are similar to inserts, except that they have a consummate frame that includes caput jamb, side jambs, and sill. These are the only option when the old window frame, sill, or jambs are rotted. To install these, you must strip the window opening down to its rough framing, within and out.

2. Measuring for Replacements

The about important pace in the window-replacement process happens long earlier installation day. Information technology's when you measure the dimensions of the existing window frame to brand sure y'all order a replacement unit that'south the right size. Here'due south how to do it.

Start by measuring the inside width of the one-time window frame, jamb to jamb, in three places: beyond the peak, middle, and bottom. Write down the smallest of the three measurements.
Next, measure out the frame's height from the top of the sill to the underside of the head jamb in three places: at the left jamb, in the middle, and at the correct. Over again, tape the smallest measurement.
Check the squareness of the frame by measuring the diagonals from corner to corner. The two dimensions should be the same. If the frame is out of square by 1/iv inch or and then, don't worry; the replacement tin can be shimmed to fit. Anything more may require adjustments to the frame. If the frame is so out of whack that a foursquare replacement wouldn't wait right, you lot'll need a total-frame replacement.
Finally, use an angle-measuring tool to determine the slope of the sill; some replacements come up with a choice of sill angles.

3. Take Out the Sash

The kickoff step is to remove the old sash from the window frame. In most cases, y'all'll need to pry off or unscrew the interior wooden stops to remove the lower sash. (If you're planning to reinstall the stops, do this job carefully; they pause easily.)
Next, take out the parting chaplet to free the upper sash. If your windows, like these, were previously fitted with sash-replacement kits, there won't be any chaplet. Simply press in on the jamb liners and pull the superlative of the sash forward.
Then pin one side of the sash upward to free it from the jamb liners.

4. Pry Off The Jamb Liners

Man Prying Off Jamb Liners For Window Replacement

If the window frame was fitted with vinyl or aluminum jamb liners, use a flat bar to pry them gratis. In the example of an original window, remove any remaining wooden stops from the window frame.
Leave the interior and exterior casings intact.

v. Prep the Frame

Man Using Flat Bar To Pry Off Jamb Liners

Scrape off all loose and blistered paint and patch any holes or cracks with an exterior-grade forest putty, such as the ones from Elmer's or Minwax.
Then sand the jambs shine, and prime and paint the surfaces.

6. Remove the Sometime Sash Weights

If the original sash weights are still in identify, take this opportunity to remove them from their pockets and insulate behind the window frame.
Unscrew the admission console on each side jamb and pull out the weights.

7. Prep For Insulation

Man Uses Drill To Prep For Window Replacement Insulation

Tom likes polyurethane cream, because it's more constructive at blocking air than fiberglass insulation.

Make sure to use only low-pressure, minimally expanding cream intended for windows and doors; annihilation else volition bow the frames and keep the sash from working.
Showtime, pull out any existing fiberglass in the weight pockets.
And so bore 3/8-inch-bore holes, one near each terminate and 1 in the heart, down through the sill and up through the head jamb.

8. Spray in the Foam

Man Sprays Foam Into Drilled Holes For Window Replacement Preparation

Shoot the expanding foam into the holes until it begins to ooze out. (Tom is using a commercial arrangement, just yous can do the same job with foam from a tin can, like Dow's Great Stuff.)
Also spray foam into the sash-weight pockets in the side jambs. Allow the excess to harden for at least 6 hours, then pause or cutting it off flush before replacing the sash-weight pocket panels.

9. Caulk the Opening

Man Caulks Along Windowsill For Window Replacement

In preparation for installing the window, use an elastomeric caulk to the exposed inner face of the exterior casings or to the blind stops on the meridian and sides of the frame. Also apply two continuous beads of caulk along the windowsill.

10. Install the Window

Working from inside the room, set the lesser of the insert replacement onto the sill, and so tip it up into the opening. Press the window tight against the outside casings or blind stops.

11. Fasten It Loosely

Hold the window in place with one 2-inch screw driven loosely through the upper side jamb and into the framing. The screw should be in just far plenty to allow the window to operate.
Close and lock the sash.

12. Shim as Necessary

Adjust the unit by inserting shims under the sill and behind the side jambs until it is centered in the space and opens, closes, and locks smoothly.
Measure the window diagonally from corner to corner; the measurements should be the same. When the window is square, screw information technology in identify through the predrilled holes.
To avoid bowing the frame, skid a shim behind the jamb at each screw, then spiral through the shim.
Trim the shims flush with a utility knife.

13. Caulk, Prime number and Pigment

Man Stands In Front Of Window Replacement To Find Gaps

From the outside, measure the gaps betwixt the window frame and the casing. Make full gaps less than i/4 inch wide with elastomeric caulk. Anything wider must commencement be stuffed with foam-rubber backer rod.
On the inside, make full any gaps around the window with minimally expanding foam.
End up by reinstalling the stops or adding new ones.
And so prime number and paint, or stain the interior of the window sash and frame.

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