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Frequently Asked Questions

Why do you recommend against installing vinyl windows?

There are a number of reasons. First, most vinyl windows are of lesser quality and durability. We believe that using high-quality materials saves money and frustration in the long run and generates far less waste. Also, vinyl plastic windows are for the most part, not repairable. If a screw strips out or a latch breaks, often the entire window must be thrown away.

As a practical matter, vinyl windows can’t be recycled. This, combined with durability issues, generates ever-increasing amounts of landfill waste. Additionally, it has become increasingly clear that the vinyl manufacturing process is extremely harmful to the environment. You can read more about the effects of the vinyl manufacturing process here:

Finally, vinyl windows look completely out of place in Chicago’s classic buildings. Even from the interior, plastic windows convey the image of a cheap, temporary place, not the solid, permanent feel that everyone inherently understands and values in their home and neighborhood.

Isn’t it less expensive to just tear out old windows and replace them with new windows?

Not usually. The reason is because quality new windows are fairly expensive. And if you try to save money by putting in cheap new windows, you will need to replace them again in only a few years. That will probably end up costing more in the long run, and there will be a lot of time and frustration spent along the way. As with most things, it pays to do it right the first time.

To give you a better idea of the relative costs of different window options, click here for a comparison chart we have put together to help clarify things.

Will window upgrades pay for themselves with energy savings?

In many cases, they will not. The exception is storm windows and weatherstripping. These upgrades are very durable and have a high life expectancy relative to their cost. New high quality windows, are more expensive relative to their life expectancy and energy savings, and thus have a long payback period. Sometimes the payback for a new window can be decades, and by the time the window is paid for with energy savings, it will likely need replacing.

On the other end of the scale, low-cost new windows, although they cost less, will also last less time, and probably offer poorer performance. Thus, they can actually represent an even worse value. See this chart for comparison.

Most building scientists and energy auditors seldom recommend replacing windows. They usually recommend other actions which provide greater benefits at far less cost.

Is it really possible for old windows to be made energy efficient?

Yes, in spite of what the major window manufacturers, and new window salesmen would have you believe. In recent years, a number of rigorous academic studies have been done to take a look at this question, and the results are clear. See links to some of the studies here.

Today’s modern dual-pane glass is very energy-efficient. But the reality is that in most windows, the majority of the heat losses around windows come from air infiltration, rather than heat transfer through the glass itself.

My old windows are 100 years old. If I replace them with new windows, with today’s modern technology, they should last at least another 100 years, right? So why wouldn’t I do that?

It is very unlikely that even the best windows being put in today will last as long as the windows put in 100 years ago. There are two main reasons. The first is that the wood that is readily available to window manufacturers today does not have nearly the rot resistance of wood that was being harvested from old-growth forests at the turn of the last century.

The more important reason is that the insulating glass units (dual pane glass) used in today’s windows has a limited life expectancy. Although this type of glass offers excellent energy performance, once the seal in the insulating glass fails, the window will fog, and the entire sash must be discarded. These windows are not repairable. The cheaper windows may fail in as little as 5 years, while the better-quality windows, such as Marvin, may last 50 years. But it is doubtful that they will last as long as the originals.

The previous owner installed new windows, but they are already leaking and do not operate properly. I want to replace them with new windows that look original. My contractor told me he can’t get windows to match the type of windows that were originally on the front of my house. Even if he could find out where to get them, he said they would be “custom” and way too expensive. Is this true?

Probably not. High-quality manufacturers, such as Marvin, have a very flexible manufacturing process and routinely make windows to match virtually anything. Also, what many homeowners do not understand, is that since window opening sizes are not standardized, virtually all windows today are made-to-order. High-quality windows like Marvin are more expensive, but most of the cost of the window is in the quality of the product. There is only a slight additional charge for specifying features that are not in the standard catalog list of options.

For this type of situation, however, it requires knowledge and skill on the part of the contractor to understand all the details and make sure the specifications are correct. If the product arrives as specified, but a mistake was made by the contractor when ordering, it becomes the responsibility of the contractor. Many contractors are not confident in their ability to get the details right, so they discourage owners from trying to do things in a historically correct manner.

The window salesman recommended vinyl-plastic replacement insert windows, and will wrap the old exterior wood trim with aluminum so I won’t have to ever paint it. Isn’t this aluminum trim a good idea?

Wrapping exterior wood trim with “coil” as it is known in the trade, is done extensively, but we do not recommend it. The main problem, besides a downscale appearance, is that it does not allow the wood underneath to “breathe”, or dry out when it becomes wet. This promotes rot. Even worse, the ongoing deterioration remains hidden under the metal, so there is no way to observe what is happening until major repairs become necessary.

In many cases, exterior trim just needs a coat of paint. When wood has started to deteriorate, we can do spot repairs with epoxy and borate preservatives, and then we coat the entire area with a water repellant preservative before painting. Although most painters and contractors are not aware of it, water repellant preservatives are absolutely necessary for most woods before painting, as proven by the U.S. Forest Products Research Lab, in years of studies dating back a half-century. Paint alone will not stop rot on the typical new-growth wood available today.

Where full replacement of exterior trim is necessary for historic reasons, we use old-growth pine or naturally rot-resistant domestic cypress, a wood similar to pine, but more durable.

I have a stained glass window that is rotten, and one of the pieces of stained glass is broken. Do you fix stained glass windows?

Yes. We do all the carpentry-related work ourselves, and have a stained glass shop we work with for the actual glass repair. If you have a stained glass shop that you prefer to use, we will of course coordinate the work with them.

Why do you use wood storm windows, when aluminum storms seem more durable?

We recommend and install both types, depending on the particular application. For the front of vintage buildings, wood storm windows provide the best appearance. We can paint them any color to match the facade. We fabricate them with low-e glass (a very important detail), and fit them to the building, so they are just as energy-efficient as manufactured aluminum storms. Matching wood screens can be made for use in the summer, or with our new designs, wood storms can incorporate self-storing storm and screen panels so they can be left up year round.

Aluminum storms (we do not install triple-track storms) do not need painting, and provide both a self-storing storm and a screen in one unit. However, they are less attractive than wood storms on the fronts of buildings. On the sides and rear of buildings, they provide a good balance of appearance and performance. They are available in a limited range of colors. Our standard color is pebble gray, which matches best with Chicago common brick. Custom colors are available, but the additional cost is significant.

See our storm windows page for more info.

I have heard that interior storms are a good alternative. Do you recommend interior storms?

Only for very specialized applications where exterior storms cannot be used. The largest cause of energy losses and discomfort in a building is from air infiltration. It is better to stop air at the outside of the exterior wall before it gets into the wall. This can be done with an exterior storm in combination with calking the exterior trim. Once air enters the wall, it can emerge as drafts anywhere- around baseboard, cracks in plaster, interior trim, etc. Interior storms stop air only around the window sash.

When I was a kid, my dad had to go up on a ladder every year and take down the storm windows, and put them back up in Fall. I don’t have time for that. What do you recommend?

Storms can be installed to be either removable from the interior, or self-storing. A properly thought-out system should not require climbing a ladder for annual removal. Se our storm windows page
for more info.

Some of the original trim around my windows is missing. Nobody makes that style anymore. What can I do?

We have equipment and techniques that allow us to duplicate most trim. In some cases, there is a modest set-up charge, but many people find this service to be practical and cost-effective.

One of my windows is cracked. I tried removing the old putty to get the glass out, but it is hard as a rock. If I pay you, it will take you hours to chip it out and that will be expensive, right?

We use an environmentally-friendly steam-based process to soften old putty without chemicals, and remove it without force. Because this requires special equipment, it usually involves removing the sash to our shop.

I have some very nice original windows on the front of my building, and I was wondering if I could replace the original single-pane glass with insulating, double-pane glass to keep the room warmer. Do you do this type of work?

We strongly advise against this approach. Although it is technically possible to remove single pane glass and replace it with insulating glass, it creates a number of problems, and seldom provides much performance improvement. Most of the energy loss through older windows is due to air infiltration, not heat loss through the glass. Additionally, the thicker insulating glass requires significant removal of wood to allow the glass to fit, weakening the sash, and changing the shape of the original sash profiles. The insulating glass is significantly heavier than the original glass putting more stress on the now-weakened sash. This additional weight will also require modifying or replacing the counterbalance system (weights or springs).

If I get a new a new window installed, how do I know what standards of quality or energy-efficiency it meets? Do new windows need to comply with the Chicago Energy Code?

Primary new manufactured windows are rated by the National Fenestration Rating Council (NFRC), and carry a sticker showing energy-efficiency data. If the windows you are considering are not rated by the NFRC, you should probably look elsewhere, because these are likely low-quality windows that do not meet any standards.

See the NFRC web site for a detailed explanation of the ratings. Chicago Energy code requires all new windows to have a U-factor of .35 or lower. Keep in mind that .35 is not at all stringent, and if windows are being replaced anyway, owners should consider finding a window with a U-value that is far lower for increased energy efficiency. Also be aware that windows that do not meet Chicago Energy Code are routinely installed by contractors in Chicago, in violation of the law.

Virtually all new window replacement projects need to comply with the energy code. There are no “grandfathering” exceptions (although some very rare and narrowly defined exemptions do exist). Repairing rather than replacing can be a better solution. And be sure to check whether you are in a Landmark district, because city ordinances impose additional restrictions on buildings in Landmark districts.

See the Chicago Energy code

Installation quality is just as important as the window itself. High-quality but poorly-installed windows will be just as drafty as poor-quality windows.

If I go with a name-brand new window, I don’t have to worry, right?

Aside from premature failure due poor installation, which is dependent on the care and knowledge of the contractor, there have been many cases of mass failure in name-brand windows.

The problem is primarily related to the fact that a modern window depends heavily on technology to achieve performance. This makes the system more complicated with more failure points than a lower-tech system, like an older window. For example, insulating glass, used in all modern windows, has seals that will fail at some future point, as compared to single-pane glass which can last hundreds of years. Any errors in the manufacturing process could accelerate failure.

Likewise, the wood used in modern windows is far less rot-resistant than old-growth wood used in the past. To compensate for this, the wood is treated with chemicals. An error in mixing a batch of the chemicals, or a change in formulation for environmental reasons, or a defect in the process which applies the chemicals could cause the treatment to fail and the windows to quickly disintegrate due to rot. Pella windows, for example, experienced mass failure in recent years, and became the subject of a class-action suit. Other manufacturers have had similar problems.

See some examples of consumers discussing their problems with this here:

And contractors talking about the problems here: