Wood windows are part of the original,
irreplaceable, historic fabric of a building. The Secretary of the Interior is explicit
about saving all original fabric where possible. Any wood window can be restored to its former
beauty by skilled craftspeople. When the superior quality of an original window is combined
with today's new technology, the result is a beautiful, energy efficient window.
The wood came from virgin forests and was more dense and enduring, due to the slow growing time it was allowed to have. The graining in the wood was also much finer.
Today's wood comes from tree farms where the trees are fed fast growth stimulants,
and the cell structure is not as dense and the wood is not as attractive.
Our virgin forests are gone.
The wood chosen for windows was clear and knotless with very fine graining, and there was an abundance of different wood species. Typically pine was used for the sash and hard wood for the trims. Today, it is difficult to buy certain wood species, and the quality is not as high.
The historic wood window systems used full dimension lumber, and sash and frames were always milled much thicker. Some of these frame members were up to 15 feet or more in length. It is no longer possible to buy this thick, lengthy lumber. Today, only laminated boards can approach the same lengths.
Older windows were built right into the wall by skilled craftsmen, producing solid, very stable windows. Great care was taken to match window trims with other architectural features on a building. The craftsmanship was precise and the tolerances tight. There were no gaps in the joinery.
All of the window joints were of mortise and tenon construction, which is the best joint possible for windows. When these joints are restored, the window will not wrack or warp, and will stay square for years. Joints on windows today are finger joints, or other styles, and are typically glued together.
Many unique window shapes and styles were created because wood could be crafted into any shape. Today's windows are mass-produced, and unusual features such as rope brickmold or lugs on the sash are very difficult to create. Older windows were much more architecturally interesting. Today's mass-produced windows are generally sterile and standardized.
The original weight and chain balance system is still the best balance system available from the standpoint of duability and service. It will last another 50 years and it is also very attractive after restoration.
"Every historic building that has the wood windows removed and discarded for a replacement window system has squandered away an irreplaceable historic element. Wood windows on historic buildings have features that are no longer possible to buy at any price." --Gail Wallace, President
1. Replacement windows are generally warranted from 5 to 20 years depending on the window manufacturer. They are meant to replace a window that has already lasted 75 to 100 years - a completely restored window will easily last ANOTHER 75 to 100 years. Why can a restored window last so long? Because the joinery on the corners and at all ends of the muntin system is a mortise and tenon joint. In our restoration process, these perfect joints are carefully pulled apart and consolidated with epoxy for an exceptionally solid joint. The mortise and tenon joint is the strongest joint in the window market, and prevents the window from warping and wracking. Replacement windows typically use finger joints at the corners and no joint at the muntins; the muntin piece is coped or shaped at the end and stapled or pinned to the stiles and rails. This is why new windows seem to fall apart within a relatively short time period - there isn't much holding them together. New aluminum windows aren't much better since they are no longer welded, but are mechanically fastened due to the thermal break. The bigger the window, the more important the joints become. The best joint available is still the mortise and tenon joint and, with an epoxy consolidation, they are in the superior category. Older windows have these joints, and a good restoration process makes them unbeatable.
ORIGINAL WINDOWS vs. REPLACEMENT WINDOWS
2. Unlike restored original windows, replacement windows are always altered from the original in some fashion due to restraints imposed by the manufacturing process. Downsizing, simplifying shapes, altering thickness, and enlarging muntins are very common. Older windows were built right into the building for stability and appearance. New windows are downsized, capped over the old wooden framing, and screwed into the old framing. The appearance of the window changes. Trim pieces are used to bridge the old with the new. Any trim used is simplified. The muntins are made wider, supposedly to accommodate insulating glass, but mainly because most replacement window manufacturers have an easier
time working with wider muntins - having to work with tight tolerances is avoided because
it takes too much precision and is therefore too time consuming.
Changing the shape of the profile is also common because the manufacturer may not have that
cutter shape or may not like to work with it. It is also common to change the thickness of
the sash and frame because it is difficult to procure thicker wood.
It is getting very difficult to duplicate a 2 1/4" thick sash in pine wood, for example.
3. The true divided lites are almost always compromised on replacement windows - from applied grids on the exterior to (for a little more reality) another applied grid on the interior face of the window. The idea is not to have the trouble of glazing each individual lite or manufacturing muntins with dimension. Flat grids are cheaper and can be stuck on to some surface. Muntins on original windows have shape and dimension and thickness; they are an architectural feature of the window. All features on an original window should be retained.
4. The new and most highly touted balance systems because they allow the window sash to be tilted inward for ease of cleaning. Yet most of these spring balance systems last for only 5 to 10 years. The best ones are warranted for 20 years. This is compared to the weight and chain balance system found on original windows which is known to last and operate well for 100 years or more. When properly refurbished, using sash chain as opposed to sash cord, the weight and chain system will easily last another 100 years.
Spring balance systems may be suitable for some smaller household windows,
but they are totally unsuitable for large windows or windows on commercial or institutional
buildings. They also downsize the sash. Additionally, no interior window stops can be used due
to the tilt feature. This means that in high wind areas,
like a high rise building or any large window such as those found on lofts or institutional
buildings, the window has nothing to hold it in place from the interior.
This has the potential to be very dangerous.
Many such windows have blown out or fallen out into the interior of the building.
The best balance system in the window market is still the weight and chain balance system -
it can carry very large doublehung windows with ease.
5. The wood used to manufacture today's windows comes from tree farms
where the trees are given hormones for fast growth. The wood is much softer than dense
original slow growth wood. Not only is the wood softer, but it warps easier, and much of
the wood has knots. Thicker lumber is very hard to buy and, when you can find it,
is very expensive. Original growth or virgin forest wood, the wood that older windows
are made of, can no longer be purchased. This original growth wood is thicker, with a dense
cell structure and very fine graining patterns that make the wood most suitable for staining.
The original growth wood also tends to be knotless and will not warp easily.
6. Many people believe that with a vinyl or aluminum replacement window, the window will
never have to be painted. This idea that the window will always be shiny and new-looking
is simply not true. The paint on aluminum will fade and the vinyl will turn dull; in fact vinyl is known to attract dirt and grime. If you look at vinyl or aluminum siding on a 15 year old house, for example, it very often does not look clean and bright but dull. Most new windows come with a 10 year warranty. No one expects the paint to last forever. Some coatings, such as a baked-on Duronar Finish, will last longer, but most paint jobs on aluminum windows last from 5 to 20 years. Our restored windows are always stripped to bare wood, and the wood is restored where needed with wood epoxies. The wood on our restored windows is sanded until velvety smooth, something which is not done on almost all new milled windows. When the surface of the wood is well prepared , the new high-tech paints will adhere very well. Most of the leading paint manufacturers give a 10 year warranty, but the paint can easily last longer if correctly applied. In addition, there are new "European" paints that may exceed US paints in terms of quality and high perforance. These paints may have a 12 to 20 year life cycle.
7. Roughness on the surface of most new milled replacement wood windows is fairly typical.
Most of the new milled wood is not sanded after milling and will have varying degrees of
roughness. Stain and even paint will not take as well on a rough surface.
In our restoration process, the window is sanded three times until velvety smooth for a very
8. A full restoration program, on an alder window includes stripping to bare wood,
both structural and aesthetic epoxy restoration, extensive sanding until velvety smooth,
and finish coats. Glazing choices and weatherstripping are the same as on a new window -
With a full restoration program, your original windows are architecturally
remanufactured and restored with epoxies to a state-of-the-art "better than new" condition.
A fully restored window will easily last another 100 years - it doesn't need to be altered,
downsized, or significantly changed in any way. The windows were designed to be in harmony with the exterior of your building and the interior of your building. Those shapes are there for a purpose, to please the eye, and they can keep pleaseing the eye for many years to come.
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