Heritage Restoration, Inc., in coordination with Rhode Island Lead Technicians, Inc., has developed a Lead Safe Historic Window Operation technique that reuses the original window balance system. These guidelines do not guarantee a final lead safe operation, since many factors may prevent a final certified lead safe system.  Preliminary consultation and coordination with a certified RI Lead Safe inspector and a licensed RI Lead Safe Remodeler is essential to guarantee a visual certification of a lead safe operation. This Lead Safe Historic Window Operation outline is meant as a guide to retain historic window fabric, introduce energy efficiency and to reduce the amount of fugitive lead dust created during a window’s operation.

This guide’s methodology shall be to provide a restored lead safe window sash system through eliminating friction between the face of the sash and the jamb, parting strips and stops. If the window operation does not create friction, and the sash are lead safe through encapsulation or removal of existing finishes, the overall window operation becomes lead safe.  On-site paint removal must follow an appropriate lead removal protocols and a mitigation plan. 

The windows must be documented to their locations following a simple floor plan or diagram.  The floor plan locates and creates a code for each opening, such as 1-1, 1-2, 1-3 for the first floor windows, and 2-1, 2-2, 2-3 for second floor windows.  First apply the code to the glass, then transfer the code to the sash side using a permanent marker, stamp or engraving tool once the sashes are removed. A weather-tight temporary enclosure system or a new storm window can act as a barrier when the sashes are removed

The Lead Safe Historic Window Process utilizes Accurate series 10UP (SEE Figure 1) equipment in zinc or bronze.  The weather stripping is standard for residential or light commercial construction. Grooving the sash next to the parting strip, and mitering the weather stripping tongues at the corners, provides a continuous air seal around the window sashes.  The weather stripping system provides a track in which the window can move, eliminating friction against the parting strip and stop (SEE Figure 1).   Looking at Figure 1, the system uses the 2, 3, 7 & 8 details, creating enough room from the parting strip and stop as to not make contact.  The 2ch and 4ch details cannot be used since it will cause friction on the sash, thus negating the lead safe system.

On-Site Procedures-Removal:

1. Employ proper lead mitigation protection, using lead safe practices per RI Lead Safe Renovator/Remodeler practices.
2. Label sash and openings prior to sash removal according to floor plans.
3. Remove the interior stops for refinishing
4. Remove bottom sash
5. Remove parting strips and discard
6. Remove upper sash
7. Wrap all sash in heavy-duty plastic; secure with duct tape
8. Thoroughly HEPA vacuum all areas where windows have been removed
9. Transport windows back to private facility
   

Workshop Procedures (If being Restored):

1. Strip all existing paint from sash and stops
2. Remove and save all glass panes from sash (expect about a 10% break rate)
3. Remove all glazing putty from sash
4. Make necessary wood repairs to sash, using, at specification’s discretion, epoxy-based wood replacement, epoxy-based wood consolidant, new wood, salvaged wood, etc.
5. Cut grooves for weather-stripping
6. Fabricate new parting strips to match existing
7. Cut back stops to ensure no friction
8. Treat sash with wood preservative mix
9. Prime all sash with oil-based primer. (Sides of sash, tops of top sash, and bottoms of bottom sash were historically never painted.)
10. Re-install and glaze glass panes. Where necessary, provide new glass (define old, new or reproduction)
11. Prime all glazing putty
12. Finish-coat sash with specified colors
13. Transport sash back to site

Workshop Procedures (If not being Restored):

1. Cut grooves for weather-stripping
2. Fabricate new parting strips to match existing
3. Cut back stops to ensure no friction
4. Transport sash back to site

On-Site Procedures-Frame Preparation:

1. Remove old sash cord
2. Open pockets and remove sash weights
3. HEPA vacuum weight pocket
4. Spray in clear finish into pocket, i.e polyurethane
5. Wet wipe weights
6. Reinstall weights and new ropes (or clean & leave chain)
7. Cut and fit weather stripping per diagram and installation instructions
8. Apply butchers wax to jams and weather stripping
9. Install upper sash
10. Install lower sash
11. Install stops

Clean-up Procedures

1. HEPA Vacuum all work areas
2. Mist all plastic sheeting and dispose of properly
3. HEPA vacuum all floors
4. Wet wipe all areas
5. If required, provide lead clearance testing at completion of project

The Lead Safe Historic Window Operation relies on the friction of the sash being eliminated from the parting strip and stop.  The Lead Safe Window Operation relies on the existing paint finishes being in sound condition or to be completely stripped.  The extent of the removal or encapsulation from window parts shall depend on the target lead exposure for the project.  If the goal is to be lead safe, consult a licensed RI Lead Safe Remodeler and/or a licensed Lead Inspector as to your necessary target lead exposure levels.