Looking for guidance on whether to repair or replace a particular window? This is a question to which not all window companies are willing to provide a straight answer. The fact is, ripping out and replacing a window is often faster and more profitable for a company than other options, yet can have serious implications if the decision is undertaken lightly or the work performed poorly. Working with a trusted window restoration contractor friend, we’ve put together what we hope will be some useful information that will assist you in determining whether to consider window repair (often referred to as restoration) or replacement.

First, a disclaimer: it’s been the experience of both other window contractors, particularly those focusing on the restoration of vintage wood windows, and myself that the best candidates for repair or restoration are those units that were installed prior to WWII. This is largely due to the old growth lumber used in their construction, a commodity not readily available anymore. Window technology also changed dramatically following the war; a housing boom took place and windows went from being largely assembled on site by skilled carpenters to being mass produced in factories. Gone were the traditional chain/rope, pulley, and weight balances. These were replaced with any number of spring loaded type balances, many of which were problematic, if not impossible to service. The advent of other changes and “improvements” to these mass produced windows created other service challenges as well. Ultimately, the merits of repairing windows that were of questionable quality when manufactured can be debated, but the decision usually comes down to the value in doing so. The good news is that a number of window manufacturers recognized the shortcomings of the units produced between say, 1945 – 1985 and worked to design much better quality windows than had been available in the previous decades. Good quality modern windows can often be easily serviced and the better manufacturers maintain a parts inventory for their products.

Whether your vintage windows are candidates for repair or replacement depend on a variety of factors, including of course their overall condition. Other assessment considerations should include whether there is the presence of rot, particularly in the sill area, which could be permitting water to enter the building, whether the components of the window are structurally sound, and a “score” of their overall performance, operation, and function. Contrary to some beliefs, the age of windows – especially older ones – is rarely an indicator that they should be replaced and may actually serve as a reminder that they can be salvaged.

It goes without saying that if the window(s) is in a vintage building of historical significance, there may be a keen desire (or even local requirement) to maintain the building’s original appearance and/or fabric. With that in mind, and with the input from our window restoration contractor friend, here’s when people will often opt for preservation instead of replacement:

  1.  When true historical accuracy is visually important, particularly on the fronts of buildings
  2.  When the windows are in generally sound condition, which makes them candidates for repair/tuneup/restoration
  3.  Where the top sash (if a double-hung window) does not need to operate
  4.  When the windows are unique or architecturally significant (such as in the case of bent glass units or windows that incorporate art glass of some form)
  5. When the restoration contractor has a good weatherization solution in their toolkit that can be applied to give acceptable modern standards of comfort (the solution will often vary from job to job)
  6. Where owners place a high value on interior vintage charm (as is sometimes the case with wavy glass or chain balances)

The further the conditions deviate from the above, the more likely it is that a high quality replacement is a better answer to the problem(s) the owners may be facing. And the decision to repair vs. replace often varies, even within the same building: Very often, front windows are more likely to meet the conditions outlined above than windows that are in a side bedroom, or a kitchen that is being gutted and remodeled.

Other considerations: When existing windows are covered on the interior with many layers of paint, the significant cost of stripping often pushes the equation toward replacement.  On the other hand, if the interior can be repainted or refinished without stripping, saving them becomes much more viable (thus stained windows that have never been painted are often the best candidates for repair). On the exterior, paint build up is often less of a problem, since an imperfect finish is less noticeable and is often behind storm windows. Painting seems to be done less often on the exterior, and tends to weather off, so there’s generally less of a need to strip finishes from exterior surfaces.

In closing, many older windows (pre-World War II, generally) can often be brought up to modern efficiency standards through a combination of window restoration and the use of a good quality storm window – either a premium aluminum one or one of our historically correct wood storms. This latter option, which we encourage many of our customers that reside in vintage buildings to consider, consists of a removable frame made from decay-resistant lumber into which one or more glazing panels is placed. Storm windows perform several functions: They cover the exposed window sash, boosting the energy efficiency of single glazed windows while protecting various components from the elements. Combination style storms also permit the glass panels to be interchanged with screens in warmer months, allowing for increased ventilation.

The choice between restoring/repairing your existing windows vs. replacing them can sometimes be a confusing one and we believe it’s generally best to enlist a trusted, qualified professional to do a thorough evaluation of the units and the surrounding openings. The professional will be able to offer insight and advice to guide you towards an informed decision. In a perfect world, restoring or repairing windows – especially vintage windows – is often the best approach from an environmental perspective, yet unfortunately not all windows can be saved. If they must be replaced, we encourage you to consider how the new windows will function, their impact on the building’s appearance, and the track record of both the manufacturer and the company installing them.