Repaint all steel sections with two coats of finish paint
compatible with the primer. Caulk masonry surrounds with high
quality elastomeric caulk.
Heavy Repair of Steel Windows. Bent or bowed metal sections
can sometimes be straightened in place by applying pressure.
Straighten bowed muntins with a wire cable and winch, applying
progressively greater pressure over several days.
the glass and protect the muntins with 2 x 4 bracing). Bowed
sections caused by corrosion may have to be cut and welded. Weld
loose joints or replace decayed pieces with new steel. Patch
small holes and uneven areas with auto body compound or plumbers
epoxy. Most hinges and hardware on steel windows are made of
bronze. Clean with mineral spirits, bronze wool, and clean
cloths , and spray with a non-greasy lubricant.
o Replacement. If a sash must be replaced, some
manufacturers make rolled steel windows and can fabricate
replicas for large orders. Standard, pre-World War II,
multi-light windows using traditional 12" x 18" or 14" x
20" glass sizes are available in industrial, commercial,
security, and residential configurations. Do not replace
with sash using other materials, such as extruded aluminum
or wood and vinyl, because they cannot match the thin
profiles of rolled steel sections. If you need help
finding product information, contact the Steel Window
Institute, 1230 Keith Building, Cleveland, Ohio 44115.
4.10.4 Weatherizing Windows. Although historic metal windows
are generally not energy efficient as built, they can be
weatherized to a level that compares favorably with that of new
windows. Caulking and weatherstripping are cheap and easy (if
somewhat time-consuming) and have a fast payback period.
Consider installing interior storm windows and low-emissivity
(low-E) glass in the steel sash. If muntins are deep enough, it
may be possible to use insulating glass. There are commercially
available replacement windows that closely match the originals in
appearance but have integral weatherstripping, thermal break
construction, and insulating glass.
Caulking and Weatherstrippinq. Caulk around masonry openings
to reduce air infiltration, then add weatherstripping.
Spring-metal, vinyl strips, compressible foam tapes, and sealant
bead types are all acceptable. Different circumstances call for
different types of weatherstripping, and any given building may
need more than one type of weatherstripping. Always use the
thinnest material that will fill the spaces, since thick
weatherstripping can spring hinges, causing more gaps.
Spring-metal clips are recommended for steel windows in
good condition. Paint the window before installing
weatherstripping to prevent galvanic corrosion of steel
from contact with brass or bronze strip material. Do not
apply stripping to the hinge side of casement windows.