Repairing double hung sash windows can seem challenging. This guide will clarify window components, common problems, and give you practical, step-by-step instructions for effective repairs.
Learning these skills will save you money and help maintain your home's historic charm. If you would a professional assessment whether or not your window sashes can be repaired, or if they need to be replaced contact us here.
If you are in the San Luis Obispo vicinity we offer restoration and replacement services, if you are outside our normal service area you can still order a replacement window sash if yours are past the point of being repaired.
Key Takeaways
- Double hung sash windows have multiple interacting components like upper and lower sashes.
- Typical issues include stuck windows, damaged cords, rotting or failing frame.
- Repairing windows is a good option if the wood rot is not extensive and still localized.
- Essential tools include a putty knife, utility knife, heat gun or steamer and safety gear.
- Regular maintenance prevents issues and keeps windows functioning smoothly.
Understanding Double Hung Sash Windows
Double hung sash windows, appreciated for their classic appearance and practicality, have two vertically sliding sashes, allowing ventilation and easy cleaning. Most historic double hung windows that were created between the late 1800's until about 1955 were built in a very similar fashion. The sash was meant to be removed by taking off the casing from the inside. In order to get to the upper sash you must remove the parting bead. This piece is typically held in with a few finish nails but sometimes it can also be covered in paint making it more difficult to remove. The parting bead can usually be removed without breaking it but in the case it does break, make sure to have wood and a table saw so you can make a replacement.
Main Components:
- Lower Sash: The movable bottom window pane.
- Upper Sash: The movable top window pane.
- Sash Cords: These attach to the counter weights hidden behind the jam and make lifting the window sashes easier.
- Jamb: Component forming the sides of a window frame. It supports and guides the window sashes, holding them securely in place and providing structural integrity to the window. In double-hung windows, jambs often contain channels or tracks that allow the sashes to slide smoothly up and down.
- Counterweights: Hidden within the frame, they counterbalance the sashes.
- Meeting rail: The meeting rail is the upper rail on the lower sash and the bottom rail on the upper sash.
- Casing: The trinm that covers the gap between the drywall and jamb
- Parting bead: Wooden strips securing and separating the lower and upper sash
Frequent Problems:
- Sticking Sashes: Usually due to paint buildup or warping.
- Broken panes: Window panes can break often times when the sash is slammed as the result of broken cords.
- Cracked and deteriorating glazing: The glazing putty on the outside of the window periodically needs to be replaced, especially if there is water infiltration
- Frame Damage: Usually rotting from moisture infiltration
- Broken Sash Cords: Limit the smooth operation of windows.
- Drafts: Result from gaps between the upper and lower sash or gaps between the sash and the jamb.
Benefits of Repairing Rather than Replacing
Opting to repair rather than replace offers notable advantages. Often times, repairing a window sash is the most economical and practical way to improve the efficiency and the aesthetics of your windows.
- Cost Savings: Repairs typically cost less than replacements.
- Historical Integrity: Retaining original windows preserves your home's authentic charm.
- Energy Efficiency: Proper repairs enhance insulation and reduce heating and cooling expenses.
If you need professional advice as to whether repairing or replacing is the right approach, you can contact us for a free assessment
Tools and Materials Needed
If you are going to repair some minor wood rot, chipping paint and reapplying glazing putty, you will need some basic tools.
It is certainly possible to reglaze a window in place but if there are other issues that you want to address it will be easier to remove your window sash to work on it.
It's advisable to have either some plastic or plywood you can secure in your window opening temporarily while you are working.
Essential Tools:
- Screwdrivers (Phillips and Flathead): For removing screws.
- Table Saw: For making a new parting bead or casing if it breaks
- Miter Saw: Cutting the parting bead to length
- Pliers: For gripping and pulling tasks.
- Putty Knife: To scrape old paint and glazing.
- Carpenter’s Square: Ensures proper alignment.
Essential Materials:
- Thin Penetrating Epoxy: Repairs damaged wood.
- Glass: If you plan on removing the glass, order replacement ahead of time or have a piece of wood you can put in place temporarily
- Glazing Putty: Secures glass panes.
- Finish nails or brad nails: Will be used to reattch the casing and parting bead
- Caulk: To cover any gaps between the casing and wall.
- Paint: To touch up casing after it is reinstalled
- Weatherstripping: There are several options for weatherstripping. Press in kerf weatherstripping is a good choice. Also, metal weatherstripping can be a good choice and doesn't require you to route or cut slots into your sash to install.
Safety Gear:
- Gloves: Protection against sharp edges.
- Dust Mask: Prevents inhalation of debris.
- First Aid Kit: Handy for minor injuries.
Having these tools and materials prepared ensures a smoother repair process.
Step-by-Step Sash Removal
Preparing for Removal:
- Clear your workspace.
- Use a utility knife to cut through paint and caulk around the casing
- Gently pry the casing off once the caulk and paint is cut.
- Use a thick pallette knife to get in between the casing
5. Use shims to create space between the casing and then a pry bar to gently pull out the nails
6. Using pliers to grip the parting bead, duck bill pliers work best if you want to keep the parting bead intact, try to gently wiggle it loose without breaking: it is typically held in with finish nails.
Safe Sash Removal:
- Gently remove the interior stop from the frame.
- Pull out the lower sash; use care if painted shut.
- Detach sash cords carefully, they are typically held in with screws. Tie a large knot or insert a nail to keep the sash cords from getting pulled into the jamb. If the cords are broken or show signs of heavy wear, you can replace them with these.
Handling Removed Sashes:
- Inspect for damage and for signs of rot and termite damage
- Store safely, it is a good idea to label all sashes you have removed to make sure they go back in the same way they came out.
Repair and Restoration
Inspection and Cleaning:
- Using penetrating epoxy to stabilize and harden any areas with rot
- Use Bondo or another wood filler in areas that need it.
- Clean thoroughly to identify hidden damage.
Common Repairs:
- If you are replacing any glass panes and reapplying glazing putty, depending on the ambient temperature and the humidity level. You will likely need to wait several days, if not longer, before the putty has skinned over and is ready to paint.
- Applying glazing can be done by hand to first get the putty into place.
- Then, using a putty knife, the excess can be trimmed off.
- Minor cracks or damage due to rot: Use two-part epoxy filler, allowing proper drying and sanding.
- Major damage: Replace damaged sections with combination of wood and Bondo filler.
Damaged Casing
- If maintaineance on your windows has been neglected for some time you may find rot or damaged casing as well.
- Some casing profiles can be very particular, and if you don't have experience milling custom profiles, you may need the help of a professional carpenter.
- To install new casing its advisable to have a small block plane, Bondo or another wood filler and sandpaper to make the transition seamless.
Painting and Finishing:
- Apply a quality oil-based primer to protect wood.
- Use multiple paint coats for durability.
- Ensure complete drying between coats.
Reinstallation and Functionality Check
Reassembling the Window:
- Attach sash cords with a set screw making sure to use the proper length screw, making sure not to go so deep as to hit the glass.
- Reinstall the upper sash followed by the lower sash.
- Reattach interior trim securely.
Operational Testing:
- Open and close sashes, checking for smooth operation.
- Confirm alignment and proper locking.
Ongoing Maintenance and Troubleshooting
Addressing Common Issues:
- Stubborn Sashes: Check for broken cords possible warping of the sash frame; lubricate if necessary.
- Regular Checks: Frequently inspect cords and window tracks.
- Preventive Maintenance: Clean debris regularly, apply silicone spray, and tighten screws periodically.
Using quality parts like the WRS Gallatin/Gapco Sash Cam ensures long-term performance and ease of operation.
Final Thoughts
Repairing double hung sash windows not only preserves your home's beauty and historical value but also promotes better energy efficiency. By following this guide carefully, you can successfully restore your windows to optimal function, save money, and enhance your home's appeal. Patience and thoroughness throughout the process ensure rewarding and long-lasting results.
Frequently Asked Questions
What are double hung sash windows? Windows featuring two vertically sliding sections (sashes) that improve ventilation and accessibility.
Common problems encountered? Stuck or hard-to-move sashes, drafts, and peeling paint are frequent issues.
Why choose repairs over replacements? Repairing saves costs, maintains original home aesthetics, and is environmentally friendly.
What essential tools are needed? Common tools include putty knives, screwdrivers, sandpaper, paintbrushes, and protective gear.
How is a sash removed? Remove the interior stop, detach sash cords carefully, and label all parts clearly for reinstallation.
What if my window won't open? Inspect for paint sealing the window shut or check for damaged sash cords; gently pry or clamp open if necessary.