How To Replace Glass In A Window

Crack! An errant baseball, a hurled stone, or a falling branch is all it takes to end the life of a windowpane. And for virtually modernistic, double-glazed windows, that means a trip to the local glass shop for repairs.

But for old-fashioned, single-glazed woods sash, y'all can hands replace the pane yourself. It's one of the rare homeowner projects that doesn't require some practice to tool the putty," says Tom Silva, This Old Business firm general contractor. "You lot want to terminate upwardly with neat, crisp creases in the corners and straight runs in between."

The reglazing technique Tom demonstrates on these pages also comes in handy when the old putty itself cracks or falls out but the glass remains intact. (In that case, Tom removes all the former putty; it'south too far gone to patch.) Whatever the glazing project, he recommends taking out the window sash and laying it flat on a workbench, if possible. "Trying to reglaze a sash that's all the same in it'due south opening takes longer, and it's far more difficult to do a skilful job."

Stride i

Remove the Glass

Don gloves and safety spectacles and cover the broken pane with a rag. Tap the middle of the rag-covered pane with a hammer to loosen the shards.

With gloved easily, jerk costless any pieces that remain embedded in the putty.

If the sash is yet in the window opening, or the pane has a fissure or two but is otherwise intact, it'southward all-time to remove the putty first, then the drinking glass.

Stride 2

Remove the Old Putty

Pry out any loose putty with a painter'south tool. Gradually soften the putty that's still intact by holding a heat gun about an inch away and moving information technology dorsum and forth.

Put doubled sheets of aluminum foil on the next panes to keep them from being cracked by the heat.

Employ the chiseled point of the tool to rake out the warm putty. Repeat on the remaining sides.

TIP: When removing putty from a pane that isn't cleaved, Tom holds a piece of metallic flashing over the drinking glass to dissipate the estrus.

Step 3

Prep the Rabbets

Pry the old metallic glazing points out of the rabbets, the grooves in the sash where the drinking glass sits.

Scrape and sand the rabbets downward to bare wood. Brush an exterior primer onto the bare wood and so information technology won't draw the oils out of the putty and shorten its life.

When the paint dries, knead a handful of putty until it's warm and malleable, and so printing information technology into the rabbets, filling them completely (equally shown). Neatness doesn't thing at this stage.

Step 4

Bed the Glass

Wiggle the pane into the putty while applying even pressure with the tips of your fingers.

Continue pushing downwardly until the drinking glass is centered in the opening and nigh one/8 inch of putty remains between the face of the drinking glass and the rabbet.

If any voids evidence under the glass, pull out the pane, add together more putty, and start over.

Pace 5

Set the Points

At the centre of each side of the pane, identify a glazier'due south indicate flat on the glass and fit the tip of the putty knife against the bespeak's raised shoulders.

While applying slight downwardly pressure level, gently rock the point from side to side until it's seated in the wood.

Repeat on the opposite side, and then on the two remaining sides. For panes 12 inches or longer on a side, space the points evenly four to half-dozen inches apart.

Flip the sash over and scrape off the excess putty that squeezed out the other side.

Step 6

Knead the Putty

Warm a handful of putty and curlicue it into a long rope about about ¾ inch in bore.

Step seven

Apply Putty Rope

Place the rope around the edges of the drinking glass and push information technology firmly against the exposed rabbets.

If one rope isn't enough, scroll out more than and overlap the ends to form an unbroken ring of putty around the edges of the glass.

Step 8

Polish the Putty

Starting in a corner, residual the putty knife's blade at about a 45-degree bending to the glass, with its tip on the acme edge of the rabbet and one corner on the glass.

Flatten the blade against the putty with your index finger and maintain the angle equally you pull the pocketknife forth one side of the pane.

Leave a corking crease in the corner — then collect the excess putty.

For the remaining sides, gear up the blade tip on the pucker and repeat the tooling process.

TIP:If the knife pulls the putty off the drinking glass, clean the blade and attempt again.

Step 9

Fine-tune

If the underside of the putty tin be seen from the other side of the window, the putty is besides broad and needs retooling.

Fix the corner of the blade on the glass a little closer to the rabbet than before and hold the pocketknife handle a flake closer to the glass.

Retool as in Step 8. You lot'll know you've gotten the angle right if the putty'southward border lines up with the inside edges of the sash or muntins on the opposite side of the window.

Scrape away the excess (as shown).

Footstep x

Prime and Paint

Look near vii to ten days for the putty to stiffen up, then clean the oily putty film off the drinking glass with a dry rag.

Paint the putty with an oil-based primer, overlapping it most one/16 inch onto the glass to prevent water from getting behind the putty.

After the primer dries, use a coat of exterior paint.

When the pigment dries, you can give the pane a thorough scrubbing.

Tools Needed