Historic Wood Windows and Storm Windows vs Replacement Windows

The Shocking Truth About Windows

How To be Smart in a World of Dumb Builders

You’ve been fooled.
The Replacement Window epidemic is just a conspiracy to take your money!

Learn how to REALLY
Save Money on heating bills – Save Energy – Save the Environment

Learn about the Design Styles of Historic Windows, Replacement Windows,
and Storm Windows and Their Affect on Curb Appeal

Find window restoration specialists in your area

Old Wood Windows and Storm Windows vs. Replacement Windows

It is true that what you have been conditioned to believe about Historic Wood Windows vs Replacement Windows is wrong.  Here you will learn all you need to know to make an informed decision of whether or not your old wood windows should be replaced.  And if you must replace, you will know what to shop for based on the design and style of your house, and which window designs to avoid.

This page is basically broken down into two parts:

Window Performance and Window Design

I have also included links to other sites providing more detailed information.  There is a great deal of information to read here, but this is something that must be done before you undertake a monetary and aesthetic investment.  I cannot stress this enough.  Let the buyer beware because there’s no turning back!

Windows are the eyes of a house.  They are the most important character defining feature creating the greatest visual impact on the overall appearance of a house.
Because of this, the decision to replace an original wood window must be carefully considered and understood.  We all want to reduce our heating bills and save money.  How can we do that with 100 year old, drafty windows that are in bad shape?  You can – there is no need to compromise.  Read on and see.

The public has been brain-washed by marketers.  Even an eight year old knows you need to replace your old windows to save energy and lower your heating bill.  What else can you expect with all the advertisements and promotions manipulating the public?  This is big business and high sales commissions are paid to highly trained people to convince you to replace your windows.  Their livelihoods depend on these sales.

Additionally, with the rush to conserve energy and make everything “green”, misinformation from the current sustainability movement has imbedded in our minds the idea that all old windows are NOT efficient and NOT green.  Financial incentives such as tax credits for home efficiency improvements have escalated the situation to a frightening degree, making old windows the most vulnerable element of a building.  The result – the consumer spends money that will never be regained – a very bad investment.  Additionally, the character of the house is destroyed forever.

Note:  The term historic window may be used to represent an original window – one that is wood and original to the house.  It does not have to be 100 years old or be ornate to be valued and worth preserving.

Circa 1750’s window shows character

Circa 1950’s window shows character too

Replacement Windows Are NOT Green
and will NOT Lower Your Heating Bills as You Think

With all of the talk of global warming and LEED (Leadership in Energy and Environmental Design), replacement window manufacturers often tout the energy savings associated with their product and that a replacement window is a “green” choice.  While this claim may correspond to newly-constructed, LEED-certified buildings, the argument that a replacement window is “greener” than a Restored Wood Window is highly debatable.

A common and often exaggerated reason for replacement windows is that new windows will significantly reduce heating costs.  This is wrong!  Studies have indicated that in most cases, approximately 10% of the heating loss of a building is through windows.  The remaining 90% loss is through gaps in roofs, walls, floors, and chimneys, with roofs being the greatest culprit.  These other areas of heat loss can be resolved at a much lower cost and result in much more savings on your heating bill than replacing windows.

Following this model, reducing the heat loss through windows by 50% will only result in a 5% decrease in the overall heat loss in the building and your heating bill.  Again – pay close attention to ads stating, a 50% reduction in your heating bill.  It is all a tactic to get you excited and interested to save heating expenses.  It is NOT a 50% savings of your heating bill – IT IS a 50% savings of the 10% heat loss through all of your windows, which will save you 5% off your heating bill.

Even with this in mind, keeping the heat in and the cold out are still prime wintertime goals. However, both goals can be met with your existing original windows.  Keeping the heat in, means insulation measured in R-value (measurement of a materials resistance to heat flow).

An old window coupled with a storm window will give you a higher R-value than a double-glazed replacement.  This is because there is more air space between the storm window and the inside window than between the two tightly squeezed panes (double pane) of glass in a replacement thermo pane window.  Believe it or not, air is one of the best insulators.  Since molecules are so far apart in air, heat cannot be transferred.  Therefore, the three inches of air space you have between the two pieces of glass performs as a very good insulator.

Let’s look at this in another way.  One measure of heat transfer is the U-value – the number of BTU’s per hour transferred through a square foot of material.  When comparing thermal performance, the LOWER the U-value the BETTER the performance (opposite of R-value).

According to ASHRAE (American Society of Heating, Refrigeration and Air-conditioning Engineers), the U-value for single glazed wooden windows ranges from 0.80 to 0.99.  The addition of a storm window proudly reduces these figures to a range of 0.44 to 0.49.

A double-glazed metal window has a U-value of about 0.60 and a double-glazed wood window ranges from 0.51 to 0.55.  Therefore, if you do not presently have storm windows, install them instead of replacing your windows.  You will spend much less money and receive much more insulation.

This U-value CAN be lowered further, but at this point we are slicing peas.  With windows accounting for only 10% of heat loss, you really do not need to look further.  However, if you want, with a Low-E-Coating Storm Window you can lower the U-value to a .32 level.

Adding storm windows is a less costly investment and, more importantly, you save your original windows (and the beauty of your house – explained later).  You will not be responsible for adding to the landfill and destroying our planet.  You can also add INTERIOR storms for even more insulation.  (More information on storm windows later)

As with nutrition labels, there is some misrepresentation of U-value measurements.
See the following link where the author advises window shoppers to make an informed decision:

Old Wood Window vs Replacement Window Energy Analysis
Here are two insightful documents that discuss the cost of replacement windows versus historical wooden windows.

The Science of Drafts and Where They Come From

What about drafts?  You can feel the same draft with brand new “top of the line” windows as well as with your old windows.  The reason for this is Convection.  This is how it works.  Glass is a great conductor.  The warm air in your house contacts a cold window glass where it cools and then draws more warm air to it.  This continues on and on until convection currents are created throughout the room and, perhaps throughout the entire house.

This draft feeling is created only because the product GLASS is used in a window.  If you really want to prevent drafts, you can use wood instead, however you will not be able to see outside.

Use of interior shutters, shades, or curtains can solve the draft problem by blocking off the glass from the warmed room air.  An additional layer of glass (storm window) which creates an air space between the two glasses will help; however, you are still using glass, and heat will still be drawn to it, although not as much.

These links from the National Parks Service can help you understand how to improve energy efficiency:

The National Park Service – Department of Interior, provides a Technical Preservation Service.  Writers working under contract with the federal government have assembled more than 40 booklets designed to help owners and developers of historic buildings recognize and resolve common preservation and repair problems.  Preservation Bulletin’s provides information on:

A great resource from National Trust for Historic Preservation:

The National Trust for Historic Preservation is a great resource for any information you would need for an older home. They also have a good section on weatherization. However their webmasters constantly move around information which results in bad links for you the reader. This is bad business. OHG and other sites would like to direct you to these links to help you but NTHP is not a team player. I have therefore removed all their links to specific articles and will supply only the link to their main page. Click to go to www.preservationnation.org

Replacement Windows are NOT Maintenance Free

A principal myth is that replacement windows will eliminate maintenance.  In a way that is true because they are disposable.  You install them; 10-20 years later, you throw them out and, again, buy new windows.  Even so, the public has been sold on the myth of no maintenance, but there will ALWAYS be maintenance.  For appearance sake alone, you certainly will be painting those windows even if they are vinyl.  They too will fade over time, just as aluminum sided homes, which were once touted as “maintenance-free” are being painted.

When wood is continually maintained, its life expectancy can be about 200 years.  On the other hand, according to studies, vinyl has a life expectancy of only about 20 years. The plasticizers in vinyl will evaporate over time, making the vinyl brittle and subject to cracking. And what cost are you imposing on future owners or your poor unsuspecting children when your venture doesn’t last?  Go with time-tested materials: paint on wood.

How are you going to replace a double-glazed pane of glass when it breaks?  Manufacturers frequently modify their product line and technology quickly changes.  You may, therefore, need to replace the entire sash and frame.  Many other components of replacement windows deteriorate relatively quickly.

The seal around double glazing can fail within ten years, resulting in condensation between the panes of glass.  This then will require replacement.  Many of the plastic and neoprene seals, which hold the glass in place in vinyl and aluminum and new wood windows, also degrade in ultraviolet light.

Insulated glass typically lasts from 10 to 25 years, with windows facing south often lasting less than 12 years.  Try to imagine locating a replacement vinyl gasket 10 years from now, or the problem of replacing a bent aluminum channel.  With your original window you can always get parts at a local hardware store. See this Wikipedia article on insulated glazing for more information.

Pitfalls of Replacement Windows – from a Contractor’s Point of View

Repairing Wood Windows

Replacement window manufacturers will often compare their product to a historic wood window that has NOT been restored or maintained – a window that would undoubtedly be drafty and inefficient.

Repairing your original wood windows is easier than you think.  Old windows were made to be repaired.  They can easily be taken apart to insert new rails or muntins (cross pieces separating the panes).  Broken parts can be remade or whole sashes can be duplicated. Rotted wood can be repaired to look like new with easy-to-use epoxy fillers (see Abatron ad below). In many cases, these windows have been in service for over a hundred years with much of their deterioration resulting directly from a lack of maintenance.  With repairs and regular maintenance, the life of these windows can be extended for an additional 50 or 100 years.

Rotted corner of wood storm window

Storm window repaired with Abatron Wood Filler

For a high quality exterior wood filler for rotted wood, I personally recommend a technologically advanced product made by ABATRON as follows:

Click here to watch video on how to repair rotted wood and purchase product
The quality of the wood your old windows are made of will not be seen again.  That virgin forest wood is close-grained and resinous.  Today’s young lumber cannot match the longevity of the historic wood.  To trash your old windows is to trash a superior material that can no longer be purchased.  A replacement window will need replacement before the old one would have needed simple maintenance.

Replacement windows are disposable and will end up in the landfill, contributing to more waste.  Multiply that replacement being replaced again every 20 years.  All the manufacturer needs to do is sit by and wait for the money to come in again and again.

Should Your Old Windows be Saved? This link is to an article published in Fine Homebuilding Magazine. It focuses on common problems with old windows, and what you can do.  Options of replacing old windows are weighed against the cost, complexity, efficiency, and preservation of historic character with a problem-and-solution approach.

John Leeke – Save America’s Windows – Do it Yourself Window Restoration

In this book John covers traditional methods and the latest in modern high-tech materials and techniques.

John Leeke’s how to videos

DIY Video: Repair & Restoration of Old Wood Windows
The Michigan State Historic Preservation Office received a grant to fund a five part video series – “Simple Steps to Working Windows”. In these detailed videos, viewers will learn what it takes to repair and restore old wooden windows.
Simple Steps to Working Windows (Part 1 of 5)
Simple Steps to Working Windows (Part 2 of 5)
Simple Steps to Working Windows (Part 3 of 5)
Simple Steps to Working Windows (Part 4 of 5)
Simple Steps to Working Windows (Part 5 of 5)

A Visual Guide to Historic vs Replacement Windows

This link from the National Trust for Historic Preservation addresses the following questions with great pictures in living color to really show comparisons.

  • Should I repair my old windows?
  • When are Replacement Windows Necessary?
  • Do the Benefits Outweigh the Costs?
  • When Replacing My Windows, What not to do?
  • Do Window Details Matter?
  • Case Studies

How You Can Help save old windows at the Old House Guy Store

Curb Appeal and Understanding The Visual Impact of Windows

Curb appeal is important and your windows – the eyes and soul of the house – are the most prominent feature that can make or break its appearance.  Understand that replacement windows will give your house an entirely different look and feel because they defy the principles of aesthetics.  Learn more about aesthetics here.Because of differences in their material and construction characteristics, wood, vinyl, and aluminum windows do not look the same, although the window salesman will tell you that they do.  Wood windows tend to have articulated moldings.  Vinyl and aluminum windows, however, have flat, square, or exaggerated profiles.  Maybe these differences are subtle to you, but they add up and alter the architectural balance of the house.  Remember, the architect who designed your house specified the windows so they would work in harmony with its style.

Let us first understand the basic parts of a window and what you must watch out for.

The Window Casing, Window sill, and components. What you need to know for proper function and design

The window casing is a molding that covers the edge of the jambs and the rough openings between the window unit and the wall. The casing provides a visual frame around the window.

The top portion, also referred to as a head casing, includes a drip cap or a cornice located above (not on) the head casing. The vertical side casing is referred to the Jamb Casing. All windows must also have a sill at the bottom. These features are designed to provide protection, and runoff for rain water. Aesthetically, these features provide the illusion of structure. The sash is the movable part of the window.

Typical one-over-one, double-hung window

Never resize the window casing.  Changing the width of the frame or the size of the opening will seriously destroy the fenestration of the building!

A window needs a casing to provide a visual frame for the window.  If a casing is less than 4 inches wide (3.5 inches wide at least), it will appear too weak and narrow to carry the load of the window, upsetting the balance of the entire house.  (One exception exists and that is only for Federal Style buildings circa 1800 – which can be as narrow as 2 inches. More contemporary revivals of this style will not work with this narrow width due to the lack of complementary elements)  Sadly, new windows will always have a narrower casing and the majority of new construction and replacement windows are absent of casings. 

A homeowner may order a replacement window and be satisfied with all the details discussed with the sales person only to discover that the window is delivered with a Brick Mold.

A Brick Mold is a wooden trim used on masonry buildings to cover the gap where the brick masonry meets the window sash. A brick mold also provides a visual frame around the window as a casing would do. The width however is only 2 inches at most. This is fine for a brick house since the window is set deeper into the brick opening, but in no way should a brick mold be used on a house with wood siding.

The problem is that the best quality window manufacturers will sell you a window for your wood sided home, with a brick mold that is only about 2 inches when you need a casing that is 4 inches wide. A non-wood replacement window is sold as one piece, so you cannot replace the brick mold with a normal casing. With a wood replacement, you do have the option, but you need to specify what you want or forget it.

Yes there are some good replacement window manufacturers out there, but chances are you will not get the product you need. You must specify the window is for a historic building even if it is for a contemporary building so you can speak to a salesperson in the right department that will understand what you are talking about. You must also understand everything on this webpage.

The siding should meet the window casing as in this photo.

On the top of the window you have the head casing. The head casing must cover the jamb casing and may also extend out (horizontally) to the sides by no more than 1 inch per side (the head casing in the photos below do not extend to the sides). The head casing board may also be taller to appear heavier than the jamb casings and provide the appearance of structure to support the weight of the building above. Do not go overboard here.

Directly above the head casing you must have a drip cap to divert away the rain water. The rain water will roll off the drip cap onto the sill at the bottom of the window, then roll off the sill away from the house to the ground. The drip cap, although small also acts as an architectural punctuation – a visual separation from the siding. The drip cap must have flashing.

Head Casing with drip cap

Head Casing with cornice/crown and drip cap.

The drip cap can also be incorporated into a cornice or crown for a more visual impact and to divert rain water farther out from the building. Each detail of the cornice is based on the ancient orders for proper architectural appearance and practicality. It is not or should not be “just a design”. Learn more about aesthetics here.

This cornice is currently available in vinyl but is overly done to a point that it looks ridiculous and does not serve the original utilitarian purpose it was designed for. Understand that you must have a casing surrounding the entire window – not just the top as the photos below illustrate.

Overly done and fake looking. The arched part of the casing ends abruptly and extends way out from the siding past the shutters. The casing does not continue around the window.

Fake looking header/cornice does not extend out to the sides to meet a casing that should encompass the window.

At the base of the window is the sill. The window sill is angled downward and not only sheds water away but also acts as a visual base of the window. NEVER omit this feature. It is both practical and visual as all design features of old windows. The sill is extended with a sub-sill angled downward with the outer edge about 1.5 inches thick. The edge of the sub-sill may extend out to each side no more than 1 inch.

Another common practice with replacing window is the crime of “Picture Framing”. This is a window casing absent of a sill at the bottom and a drip cap at the top. It looks like and is constructed like a picture frame with mitered joints at all four corners allowing easy infiltration of water. Never picture frame a window!

As you see, changing the window casing can really hurt your house.

NO window casing – just a hole in the siding covered over with glass.

Picture Framed window. No drip cap or cornice, no sill as a base, but mitered corners to allow water infiltration.

What is a Proud Window?  Is it Possible to Manufacture an Uglier Window?

The term “Proud Window” is a term I use to describe a certain type of window you really need to be aware of. There is no official term for this window. If you describe this window to a window salesperson, they will probably not understand what you are talking about. They will just say there are different types of windows. In all my “fake” shopping to write this, no-one gave me a solid answer. So read this, understand this, and be prepared when you go into battle window shopping.

A Proud Window looks like a one piece frame and sash all encompassed in one.  It looks like the window was snapped into the house from the outside, and actually it has.  It can’t possibly look more cheap and ugly.  Instead of the window sash being recessed about 3 inches in the window casing, the Proud Window sash is flush or protrudes (is proud) from the window casing and the siding on the house.  This creates the flattest look possible since the window is absent of shadow lines.  Shadow lines on a home create the character we all love in architecture.
Never use a Proud Window!

Proud window with picture framed casing.

Proud window without pictured framed casing.

Picture framed window is NOT entirely proud to the siding as the others, but should still be set deeper into the building.

Picture framed window features the correct depth – about 3 inches.

Window Details and Measurements to Understand and Follow

You have seen the photos of bad windows. Let us now take a look at an example of an old window to better understand the measurement details and what you need to watch out for.

Here is an example of a profile for a double hung window. (If you have a scrolling mouse, hit the Control key and scroll to enlarge this photo if needed.) The photo on the left is the window in its natural state and that on the right has window parts colored to make it easier to see. Please kids – do not do this at home. Old House Guy is not responsible for homes with rainbow windows!

Let’s begin with the lower window sash (movable part of the window) since that is set the farthest distance from the face of the house and provides the most depth and shadow. The lower window sash is held in place (on the exterior) by a Parting Stop (yellow). The Parting Stop is a 1/2 inch piece of trim that holds the lower sash in place on the exterior and holds the upper sash in place on the interior side (interior portion is not visible).

The Parting Stop (yellow) also creates the inside edge of the Sash Channel (green) for the upper sash to slide down in when opening. To provide better summer cooling, the upper sash can open by sliding downward in this channel. Earlier windows have a stationary upper sash. The Sash Channel (green) is usually about 1 3/8 inch depending on the thickness of the window sash.

Next we have the Blind Stop. The Blind Stop (light blue) is approximately 7/8 inches thick. The blind stop holds the upper sash in place by creating the exterior edge of the sash channel. Without the blind stop, the upper sash can fall out and hit you in the head.

The Blind Stop (light blue) frames the entire window and rests at the bottom on the edge of the Sill (dark blue). The Sill (dark blue) extends from the front edge of the Blind Stop back to the interior sill/stool. Both upper and lower sash channels rest on the sill. The sill is angled to allow water runoff.

Between the Blind Stop and the face of the window casing is a space approximately 1 to 1 1/4 inches (lets round to 1/1/4). This area of the Window Jamb is shown in purple. This is the space that will hold a wooden storm window or shutters. The shutter or storm window must be sized correctly so it would fit inside this purple area, lay firmly against the blind stop on the inside and be even with the casing on the outside. At the bottom it leans against the Sill (dark blue).

There is a Sub-sill (orange) the storm window or shutters would sit on. (Some older windows only have a single Sill that extends out as the Sub-sill does.) The Sub-sill is also angled for water runoff and extends away from the house so water can flow onto the ground below and not onto the house. The edge/nose of the sub-sill extends outward about 1 inch from the face of the window casing.

Additionally underneath the Sub-sill near the edge is a Drip Edge. The Drip Edge is a groove in the wood that prevents water from running under the sill to the siding. The sharp edge creates a barrier that the surface tension of water cannot cross creating a drip line. Although probably filled with paint on most old homes, this slot should be maintained for water running off the sill and down the front, can due to surface tension, travel along the bottom of the sill and into the siding.

There is a lot going on here, but the point I am trying to make is the distance between the face of the building and the window sash.

The distance from the face of the window casing to the upper sash on an average window is about 2 inches.
(7/8 + 1 1/4 = 2 1/8 inches )
The distance from the face of the window casing to the lower sash is about 4 inches.
(1/2 + 1 3/8 + 7/8 + 1 3/4 = 4 inches )
Add an additional 1/4 inch for window glazing. Remember you do not get that nice 1/4 inch beveled edge with replacement windows.

This recessed space creates a nice sharp shadow. This is what makes old windows pop and creates the character we all love! New replacement window sashes change all of this. To accommodate double panes of glass the window sash must be a lot wider. This brings the sash soooo much closer to the face of the casing which prohibits the look we are accustomed to.

Windows on Brick Buildings

Windows on a brick building are a bit different than those on a wood sided building.  The windows are set deeper into the exterior wall of the building.  Instead of a wide casing framing the window on the face of the siding, as described above, there is a brick mold trim surrounding the window.  Since the windows are set deeper in the building wall, the brick mold which sits inside the wall is therefore much narrower.

As you can see it provides depth and a pleasing appearance.

Brickmold trim is often overlooked when ordering windows for Brick Homes. This is usually because the homeowner was not aware of it, nor were they told about it by the salesperson.

Window with brick mold makes a statement.

Window without brick mold looks undressed and bare.

The Window Sash

The Window Sash is the part of the window that moves up and down.  We will mostly be discussing Double-Hung windows.  Double-hung refers to the window sash – an upper and lower movable window.

Double-hung windows were technologically designed to cool a house during the summer months.  On your original windows, each window sash moves up and down.  If you lower the top sash a few inches and raise the bottom sash a few inches, you have free air-conditioning. Heat and humidity leave the house through the upper opening while the cooler breezes enter the house through the lower opening.  This natural circulation of cool air replacing warmer air of a room can really lower your electric bill. However, the upper sashes of many old windows on houses have been painted closed over time. There is a special cutter available to unfreeze that sash and get them working again.

The width of the sash on replacement windows can also be different to that of your original windows.  This may seem minor, but it does affect the appearance of your house.

True Divided Light Windows – window panes

True Divided Light is a term for individual panes of glass in the window sash.  Not one piece of glass providing the look of panes divided (separated) by a grill.

In a True Divided Light window, each window pane is a separate piece of glass.  The glass is referred to as a “light”.  The “lights” or individual panes of glass are held in place with a Muntin – a thinner piece of wood dividing the lights – similar to the tick-tack-toe pattern.

Windows with true divided lights sparkle when viewed from the street.  If the glass is older and wavy, they sparkle even more.

Since muntins are made of wood, they provide a small shadow line on the glass pane. This makes the window pop with life and character, and changes with interest as the sun travels and the lighting changes.

Today’s Replacement Windows, instead, offer one piece of glass with a flat plastic grill attached on the interior to imitate the look of window panes separated by muntins.  The result is a very shallow, flat, and bland, not to mention cheap, appearance.  It appears as if it were painted on the glass.  Better options exist such as grills on the exterior and interior etc.  Fake window grills on both the exterior and interior must have a spacer in between to give the appearance of real muntins.  However, they are still not true divided light windows.

Six-over-six true divided light window

Picture framed replacement window with plastic grill

Two-over-two true divided light window

Two-over-two with plastic muntin

The original window

The replacement window

Full view of original window. Thankfully a few windows in the back were saved.

1903 Carnegie Library, Freehold NJ – this is the type of window they used as a replacement. What kind of people would approve this replacement?

Window cleaning is much easier with snap-in, snap-out grills.  But, do you clean your windows so frequently that you’re willing to sacrifice the beauty?  True divided light replacement windows are available, but few people will spend the extra money.

There is one more thing to keep in mind about muntins.  The profile and appearance of muntins are dependent on the period and style of your house.  Even with a good wood replacement window, muntins are not a one size fits all.

Another problem with replacement windows designed to resemble true divided light windows, is the size and shape of the grill or lights.  All window panes (lights) should be vertically proportioned and, on occasion, square.  They, as in all architectural features, resemble the human form or human eye.  This is pleasing to your subconscious mind.  Learn more about aesthetics here.

Aesthetically, you should never have horizontal panes,  although during the Arts & Crafts period, this style of architecture tended to veer away at times from the traditional vertical window pane.

There is a hierarchy of windows most notable on Colonial Revival architecture when the 2nd floor windows will be a bit smaller than that of the main floor. In this case, the smaller windows should have the same size panes but fewer of them or the window and the panes should both be proportionally smaller compared to the larger window.

Keep windows to just a few similar proportions not styles.

An architectural blunder. Rectangular and square window panes. Obviously this house was not designed, nor meant to feature six-over-one or four-over-one windows. One-over-one windows would work better.

The McMansion – famous for poor architecture, boasts a mish-mosh of types, sizes, and styles of windows unrelated to each other or the architecture. This upsetting rhythm causes you to leave with confusion and think that a lot of money was spent (foolishly wasted) so it has to be good! (see http://en.wikipedia.org/wiki/mcmansion)

It is obvious this window was designed to be two-over-two windows, not four-over-four, sadly making the statement “bad replacement window”. One-over-one would look more normal.

Beautiful old wavy glass windows on the first floor. Replacement windows on the 2nd floor have plastic dividers to now make the window four-over-four. If the replacement window was two-over-two, the window panes would match the first floor. If painted black it would not look as distracting.

Vertical window panes (correct) in the main portion of the window, and horizontal panes (bad) in the transom shows a poorly designed window. The transom window panes must match the vertical panes below. If a single vertical pane in the transom would be taller than those below, then the transom design must be made to accommodate the proper size windows – not the other way around.

The size of the window casings are correct for this house on both the first and second floor. As you can see, there is no easy way to divide these windows into separate equal sized panes. This only means that the window/house was not designed for this type of window. A two-over-two or one-over-one would make the house more visually appealing. Also – the double-hung windows were replaced with casement windows which is bad.

As you now see, few elements of a building contribute more to its architectural character than do the windows and window sashes. Although all this information you are reading may seem lengthy, I encourage you to read the information on the following topics for a complete understanding.


  • The evolution of window sashes and muntin profiles
  • Three types of Window glass prior to WWII
  • Window hardware
  • Casings, shutters and blinds interior and exterior
  • Wood sash problems and solutions

These topics are discussed here by James L. Garvin of the New Hampshire Division of
Historical Resources.

Does the Window Style Match the Style of my House?

One of the biggest mistakes people make is replacing their windows with a style that’s wrong for the house.  Style and period of house come into play here.  Window glass was expensive and smaller sized panes of glass were all that was technologically available.  During the 1700’s and into the mid 1800’s, a double-hung window sash would be composed of smaller, true divided lights.  The upper and lower sash could have 6, 9, or 12 window panes in each sash.

To explain better, a double-hung window (window with an upper and lower sash) is referred to as a one-over-one window.  One solid pane of glass was inserted in the upper sash and one in the lower.  Six-over-six means, six window panes in the top, and six in the bottom.

As technology improved, larger panes of glass became available.  Houses constructed after the Civil War (Victorian architecture) would most likely have two-over-two windows.  The Colonial Revival style of architecture would have six-over-one windows.  Although the late 19th century offered one-over-one, the type of window was dependent on the style of architecture at the time.

I know of architects (not preservation architects of course) that, unfortunately, were involved in restorations, and recommended six-over-six windows for a Victorian house.  How awful!  This window style predates the house.

Now you may ask, why would a 1790 house have two-over-two windows?  This is because the original six-over-six (or higher number) windows were replaced during the later 1800’s with what was available at the time.  Although not period correct, it is part of the evolution of the house which is an entirely new topic of discussion!

The bottom line is Buyer Beware!  Do not depend on a salesman to tell you what is right for your house.  They will say you have an old style house and give you a watered down version of a window that is wrong for your house.  They are not trained in architecture, but are highly skilled in making a sale.

An example is in the photo below.  This is a CRIME to Architecture!

This Italianate house once had beautiful two-over-two, arched windows.  Notice the arched window frames.  The frames are still arched on top, but have been filled in below the arch so that rectangular replacement window sashes can be installed

Additionally, nine-over-nine windows were installed which provide a Colonial/Federal look popular long before this house was built.  Either the owner had a thing for George Washington or just didn’t care.

While we’re on a roll, the black paint accentuates the remodeling errors and the vinyl siding results in loss of detail and shadow lines making the façade look flat and bland.

As you can see this is the office of Century 21 Realtors.  One would expect that specialists in the business of selling houses would know something about elementary architecture.  If not, they should ask someone that does.  One would also think that the window salesperson would have some training.  Again – Let the buyer beware!

So, this really annoyed me and I called the realtor’s office and told them the building looked absolutely awful.  I also listed their phone number by the photo on my website.  About a year later, they corrected most of their errors.  Maybe readers like you called too!

Not understanding paint color placement, just draws your attention to the many problems with this house.

Nice improvement! Two-over-two windows are correct for the architectural style and the colors work nicely.

As you can see, the side of the house looks bad. Nine-over-nine windows and a fake cutesy window surround that is supposed to fool us to look like it resembles the arched window in the front. Too bad they couldn’t continue with the improvements they make in front here.

Never Replace a double-hung window with a Casement Window

Casement windows have their place in certain styles of architecture, but if your house was designed for a double-hung window, that’s what it should have.

Even though the one-over-one double-hung window on the left is a cheap replacement, it still provides a better appearance than the casement window on the right. Also note the frame of the casement window is wider than it should be.

One window looks bad, but here you can see how it really affects the appearance of the entire house. Casement windows provide a “blank stare” look. This house reminds me of a jack-o’-lantern with its windows appearing like holes cut out.

This casement window has a plastic grill. Casement windows are great on certain types of architecture such as English Tudor. When installed in architecture not specific to the design, they appear strange.

Old Windows are Part of History

The replacement windows you are being peddled will degrade its historic value.  The size, configuration, materials, and milling of the windows tell a story about your house.  They are a visual record of the period in which your house was built.

There is also a direct correlation between historic integrity and market value of houses.  A preserved old house will bring a higher price than an old house remodeled to look like something it never was.  Please be very careful in deciding on a window strategy.

And if you’re a person that has no concern for history – it doesn’t matter – it’s all about curb-appeal, and curb-appeal is based on aesthetics.  Learn more about aesthetics here.

The following link is to a study about Historic Preservation and its impact on house values:

If You Must Replace your Wood Windows

If the degree of deterioration necessitates the replacement of windows – not laziness, wood replacement windows are recommended.  It is extraordinarily important that every effort be made to match the style, the muntin profile, and shape.  Altering any of these features will make a dramatic change in a building’s overall appearance and its setting within your neighborhood.

The first thing you should know, if you must replace your wood windows or anything on your house, with a product different than that you are replacing – use the “Arms Length Rule”. That is, the product must be indistinguishable from the original product and material at Arm’s Length.  Keep this in mind and you won’t be sorry.

A wood window has to be pretty far gone before it needs to be replaced.  Modern weather-stripping can be installed, sashes can be rebuilt, and reproduction period glass can be reinstalled.  Even severely rotted wood can be strengthened and rebuilt with durable epoxy fillers.

However, as important as old windows are, there are cases when a window must be replaced due to extreme deterioration.  In such cases, you should duplicate the original window exactly.  Never modify a window opening to take a smaller or larger window.

Today there are alternatives for replacement windows.  Most window manufactures offer at least three options: the cheapest (and it most definitely LOOKS the CHEAPEST) is the snap-in, removable grill or muntins, designed to fit a sash with a single large pane of glass.  DO NOT settle for these fake snap-in muntins sold by Anderson and other manufacturers.

A second option is what is called a simulated divided light, which consists of muntins that are permanently attached to the interior AND exterior panes with a durable adhesive.  Although a better option, please be sure that there is a spacer in between to give the appearance of real muntins.

Then the third and best option, ASIDE from restoring your original windows, for true divided lights, is to look for a manufacturer that makes all-wood windows.  Cedar Windows by Bergerson, for example, manufactures custom windows in rot-resistant cedar.  The wood goes all the way through and separates the window panes – true divided light.  Divided light gives windows that sparkle.  There are other manufacturers such as Pella and Pozzi that make windows to match your existing windows.  When I spoke to a representative from Marvin Windows, I was told that they would even install Restoration Glass.  (Restoration Glass is new glass made with slight distortions which create that extra sparkle glass had years ago.)

Although there are options to choose from and costs to consider, the lower cost windows (which are still expensive) will definitely look as if you cut corners.  For such an important feature on your house, your dollars will reap more rewards when choosing an exact match.  Otherwise, you risk altering the architectural appearance.

If the original windows are already long gone, a historically sensitive choice can dramatically improve the house’s appearance.  However, deciding to buy the most expensive replacement window does NOT guarantee curb appeal and the best window for your house.  Please do not depend on the salesperson’s knowledge of matching a window.  You must thoroughly understand the design features and become your own expert.  This is unfortunate but the only way to insure success.

Before ordering windows, I would first check your local phone book under Furniture Makers or Carpenters.  You will need to do some good investigating.  Find someone who can do custom woodwork and can make windows for you at a much lower cost without paying for the manufacturer’s name.
NOTE: If you replace your original windows, don’t let them end up in the landfill. Store those windows in your attic in an out of the way place. Think of future owners who will be so happy to find those windows and restore them back into use. Just because you don’t want them doesn’t mean a future owner will not. Think of it as a good deed.

Half bad

Super bad

Left Photo:
The bank in the above photo was built in the 1970’s with true divided light windows as you see the window on the ground floor.

Later, the second floor window was added – God only knows why.  The window is called a “wart-window” (window that resembles a wart or tumor growing out of the building).  This architecturally wrong window conveys the illusion of a wart because it is absent of brackets which would create the illusion of support.

As you see the second floor windows are also Proud Windows with plastic grills.  Compare the upper floor to the lower floor.

Right Photo:
Sadly, a few years later the first floor’s true divided light windows were replaced with fake plastic grills.

You can compare the beautiful true divided light windows on the ground floor (Left photo) with cheap looking snap-in grills (Right photo).

One more thing since I’m on a roll.  The style of both the first and second floor window on the left is architecturally correct in that it does NOT contain siding as in the photo on the right.  Additionally window panes should be similarly proportioned throughout the building.

Do you hate these windows too?  Call Freehold Savings and tell them (732)462-6700.  Call Code Enforcement who allowed this to happen (732)462-1410.
So sad – although a contemporary building, the true divided light windows created shadow lines which gave it character and depth.

Curb Appeal and the Appearance of Storm Windows

As stated earlier, the use of storm windows will give you the best energy savings.  The bad part is that they detract from the appearance of your house.

Windows are recessed in the casing.  This provides depth and shadow lines, stimulating your senses, and creating interest.  If the window is multi-paned, the muntins create additional interest.  The unique thing about all those separate panes of glass is that each reflects light a bit differently.  Passers-by see a dancing reflection as they adore your home.

That effect, subtle but important, is lost when a single sheet of glass is placed over such windows.  You lose some of the sense of depth created by a three dimensional effect. (Although this still looks better than a bad replacement window).  This problem is also encountered with the use of full glass storm doors.

So, what to do?  To solve this problem, more and more people are putting their storm windows INSIDE the house.  This allows your prime windows to face the world in all their glory, solving the “blank stare” problem encountered by covering divided light windows.  Here you get the best of both worlds.

However, exterior storm windows serve another purpose.  They protect your window from the elements.  This is additionally important since it will add years between maintenance.

Besides protecting the wooden inner sash from the elements, aluminum storm windows also protect against condensation. Because the glass of aluminum storm windows is colder than that of the wooden windows, moisture will condense on its glass, circumventing condensation on the inner sashes of the wooden windows. The metal frames of aluminum storm windows cannot be harmed by moisture. They safely handle condensation as long as wooden window sills are kept painted and the weep holes at the bottoms of the aluminum frames are kept open to drain properly.

There are also the old style wooden storm windows.  These windows are usually hung from hooks at the top of the window or held to the window frame with clips.  They are awkward to install and require storage space when not in use.  Once the springtime arrives, these storm windows can be removed.  They are done protecting and insulating your windows during the winter and can be stored away allowing your beautiful window to show itself off.

So as you see, beauty comes with a cost, but the cost isn’t what the advertisers say it is.
Nevertheless, it is always better to install a storm window (they are reversible), than to replace the original sash to prevent heat loss.

Remember – Windows are the eyes of the house.  Beautiful windows (eyes) sparkle and send a signal of warmth and create interest.  The Door is the mouth of the house which (if there is no storm door), creates a feeling of welcome and a desire to enter as it draws you inside.  See for yourself.  Does a house with a storm door seem more inviting than one without?

With wooden storm window

Without storm window

Even the old-style wooden hung storms detract from a house.  Instead of the window sash being recessed in the window, the storm makes it even and flat against the house.  Also, notice that the glare from the second piece of glass in the storm window, results in the inability to appreciate the added feature of true divided light.  That’s my doggy named Monkeyface watching you out of the mudroom window.

Arched storm window

Arched window filled in and squared off to accept a less expensive storm window. The arched windows are a character defining feature of Italianate architecture now lost on this house.

These two houses, built by the same builder are located next door to each other.

Both have beautiful arched Italianate windows and both have good quality storm windows painted to match the sash.

One owner (top photo) took the extra step and installed arched storm windows so that this beautiful feature can be enjoyed, while the other used rectangular storms and filled in the gap with wood at the arch.

Note: The darker storm window creates a nice illusion of depth on both buildings.

Caution about Color

Warning – warning – warning! Be careful using white. If the base color of your house is not white or the trim on your house is not white, then your window sashes must not be white. There is nothing worse than seeing some great house colors but the window sashes are painted white. Vinyl windows CAN be easily painted with latex paint. See the effect white has on windows in the photos below.

Unpainted White replacement window sash visually jumps out and attracts your eyes to a bad window

See the big difference from that harsh white. Vinyl is painted tan and provides a softer feel.

Although the windows are bad replacements, the dark colors add depth.

Another historically appropriate color improved the appearance of this house.

Here are a few links with additional information

Graph of Heat Savings Based on House Type and Window Type

More Window Articles and Links

(Note: Many other links can also be found on the National Trust for Historic Preservation’s site.)

Old House Guy List of Window Repair Businesses

Are you looking for businesses that do Window Restoration, Repair, and Fabrication? We’ve compiled a list for you!