Historic Wood Window Restoration
Vintage wood windows provide the character, authentic period detail, and beauty to a building or home. Repairing original windows preserves that historic integrity, and is "green" for the environment as well.
"The quality of new wood from managed forests, tree farms and fertilized stock is no match for that of early, natural-growth wood that comprises historic window frames and sash."
--from period-homes.com April 2009 Newsletter
Our historic window services begin with basic rehabilitation to restore operability, replace glazing, and performing certain repairs. Full restoration services extend beyond to include:
- Window assessment and inventory
- De-glaze and lead paint removal
- Joint stabilization and structural repairs
- Wood epoxy application or component replacement
- Finish sanding
- Introduction of historically appropriate wood preservative
- Re-glazing with original single pane glass or various dual-pane options for energy efficiency
- Painting & staining to match any finish requirements
- Exterior sill repair or replacement
- Hardware restoration or replacement
- Weather-stripping and insulation
River City Window Works has the experience and resources to perform every aspect of historic restoration from removal & board-up, restoration and rehabilitation, reproduction, finishes, and re-installation. Our proven process for historic window restoration has been very successful, efficient, and predictable. All our craftspeople have been cross-trained in each procedure, and strictly adhere to preservation guidelines for window restoration. We maintain the highest levels of quality control, and are always refining our efforts so we can pass along these efficiencies to our clients in the pricing.
On-site Sash Removal and Window Inventory
The first step in conducting a window restoration project is to document the existing conditions of each window as the sashes are removed. The team uses our architectural window schedule to record the visible work to be done. Each sash is marked in the field to correspond to the schedule in order to insure accurate tracking and processing of that sash until it is re-installed in its original place.
De-glaze and Paint Removal
Back at our shop, the next step involves removing the glazing putty and glass. Each pane is labeled with the sash number and light position so it may be returned to its original position. Next we remove the many layers of lead paint and previous finishes to determine the actual condition of the window unit and prepare it for rehabilitation.
Sash Stabilization & Structural Repairs
Great care is taken to rebuild or reconstruct the sash joint using wood epoxies, polyurethane glue and wooden dowels to re-stabilize the sash joints. The sash are then squared, clamped in place, and left overnight for the next day’s process.
Deteriorated Components Replaced
There are instances where window components are deteriorated beyond repair. When this occurs our craftspeople are able to manufacture replacement sash components matching the same profiles, sizes, and shapes as the existing parts to replace these deteriorated areas. In most instances we are able to make these components using our inventory of historic lumber.
Wood Epoxy Repairs & Wood Fillers
Using Dutchman techniques and liquid epoxy, we can repair surface cracks, gouges, missing sections, and broken profiles. Depending upon the condition of the wood, it can take several applications of the epoxy to completely permeate the damaged area, but once restored, a sash can be as durable and weather resistant as originally built.
We have a two-step sanding process, initial sanding using orbital sanders and finish sanders, and then hand sanding for a final finished surface. If necessary, we have scrapping knifes to match the profiles to effectively sand edges and corners of the sash profiles.
After sanding is completed each sash receives multiple applications of a boiled linseed oil based, wood preservative. The preservative is applied in successive coats until the sash is saturated, then left to cure. This important step helps to protect against compression dents, checking, cracking and shrinking. It also helps to waterproof the wood and leaves a nice finish to apply oil based primer.
We often re-glaze the sash with original single paned glass using traditional glazing putty methods. However, we have completed double pane or specialty glass glazing options in some of our restoration projects. Often with commercial building property owners, they are looking for energy efficiency improvements and reduced maintenance expense, as well as safety and building code requirement improvements. Insulated glass units, or "IGU’s” is a viable option that should be considered for many historic restoration projects.
Painting & Stains
Our painting crew can match any finish desired. We will use any of the major paint manufacturers, but recommend using only the highest quality finishes. We can conduct paint analysis to achieve color matching, and provide samples on representative substrate for the architect/owner approval, as well.
When the sills are in need of repair our crews follows a strict guideline for sill restoration. Existing paint must be removed from the wood sill down to bare wood and up each side of the frame jamb a minimum of 2". Where the jamb frame and the sill meet we rake out any old paint or old caulking and from beneath the sill and we treat it with liquid wood epoxy. We continue to treat the wood sill and partial frame member until the material will not absorb any more, and then we apply wood epoxy. All of the checks and gouges in the sill are filled, sanded smooth, and primed ready for painting. If required, we complete the same procedures on the frames and wood trim on the exterior of the window.
It is common to find window hardware missing or damaged on a typical restoration project, so we have relations with several vintage hardware suppliers that can supply old designs from a vast inventory of original locks, lifts, and pulleys, or we can source reproductions. For existing original hardware we remove all layers of paint and oxidation, clean and polish, and apply a clear coat finish or we can have the hardware re-plated.