Restoring an Antique Window Sash

Article 119: Restoring an Antique Window Sash

By: A Woodworker Who Sees Charm in Old Glass and Wood

Restoring an old sash window preserves history and function. This guide focuses on repairing wooden joints and reglazing panes.

Assessment

• Loose joints, cracked muntins, chipped paint, failing putty

• Replace rotted parts with matching wood

Materials

• Matching softwood (pine or fir)

• Wood epoxy or dowels

• Glazing putty

• Linseed oil

• Glass (if replacing panes)

• Primer and paint

Tools Needed

• Putty knife

• Chisel

• Small hammer

• Paint scraper

• Utility knife

• Glazier points

• Brushes

Steps

1. Remove Old Glazing

   • Use heat gun or putty knife to soften and lift putty.

2. Free the Glass

   • Carefully remove and label for replacement.

3. Repair Joints

   • Reglue loose mortises or reinforce with dowels/epoxy.

4. Prime and Reglaze

   • Prime wood; reset glass with points and fresh putty.

5. Paint and Finish

   • Paint sash with durable exterior paint or linseed oil-based finish.

Visual – Sash Corner

Top-down View:

 |--|       ← Glass
 |  |
 |__|       ← Wood sash with glazing putty beveled in