Replacement Windows 101

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Replacement Windows 101 2017-05-19T03:28:12+00:00

Here’s some basic information about the various window products that are available to you in the industry today. Whenever you look at any window, it’s comprised of two basic components… the Frame…and the Glass.

There are actually three basic materials that a homeowner has to choose from to use as a window frame. One is wood, one is a metal frame and the other alternative is all vinyl. Now there are advantages and disadvantages to each of them. Let’s look at the pro’s and con’s of each.


Most homes we visit currently have old dilapidated wood windows. These homeowners are experiencing real life testimonies attesting to the problems associated with wood frame windows. The fact is that wood expands, contracts, warps and is considered high-maintenance.

Metal Frame Windows:

Metal frame windows are strong, durable and will last forever. Most all-industrial and commercial buildings have METAL frame windows due to their resilience. It’s a one time job. They remain operationally sound and seldom have any kind of mechanical problems. They have the highest life expectancy of any other alternative. Aluminum, or metal windows in general, will always stay true, square and plum. Expansion and contraction are not factors here – consequently metal windows are known for having tight tolerances, eliminating any problems associated with drafts.

Unfortunately, there are some drawbacks. For one, they have an institutional appearance.

But they not only look cold, they ARE cold. Metal windows are so HIGHLY CONDUCTIVE that they quite readily transfer heat and cold straight through their frames. People’s fuel bills can actually increase as a result of having metal frame windows.

Vinyl Frame Windows:

Vinyl is known for two major benefits. One, it is considered a relatively low-maintenance material. It is nonporous, and unlike wood, it doesn’t need to be painted. The color is the same throughout, so any nicks or scratches appear inconspicuous. It is also a fantastic insulator (a nonconductor). This material acts as a thermal wall keeping the cold from penetrating in the winter and the heat from entering in the summer. Many companies have capitalized on these benefits over the years to provide consumers a low maintenance and a well-insulated window. However, there have been some major problems associated with vinyl replacement windows. The reason is…not all vinyls are created equal.


Practically everyone has good, positive feelings about recycling… as they should. And when it comes to recycling plastics for the production of milk jugs, toys or any other type of short-lived commodity items, the use of recycled vinyl is just fine. However, there are major concerns when it comes to making replacement windows with recycled plastics.

The problem is due to the impurities in the vinyl as a result of the recycling process. This inferior blend causes the finished product to become brittle in comparison to products made from 100% pure virgin vinyl. Because of the severe environmental conditions that windows are subjected to, the expansion and contraction of the vinyl can wreak havoc on a window. This typically results in the vinyl cracking and becoming permanently distorted. The end result… air and water leaks.

Also, keep in mind that replacement windows are custom made. Therefore they cannot be MOLDED like a milk jug or a plastic container. Windows must be fabricated. In fact, there are twelve corners that must be fastened together on a traditional double-hung window (3 sets of 4…two sashes and one master frame).

Now here’s the problem… you can’t fusion weld these corners with recycled vinyl. Therefore that leaves only two options. One is to mechanically fasten the corners with screws. This will eventually result in an unsightly separation on the corners. The second option is to chemically glue the corners. The constant expansion and contraction will inevitably cause the sealant to fail and again result in separated corners causing water and air infiltration.


They don’t make vinyl bridges, and they don’t make vinyl ladders. Why? Vinyl just isn’t strong enough. And using vinyl to support the weight of heavy glass is no different… whether it is 100% pure vinyl or recycled vinyl. In time the weight of the glass will cause the sash frame to sag. This is referred to as the smiley face phenomena, and it has plagued the window industry. The end result is seal failure, water/air infiltration, and locks that don’t engage.

Now lets take a look at the second component… the glass.

When you look at any given window, 90% of it is obviously made up of glass. However, too many people just accept things at face value when it comes to buying windows. Don’t make the mistake of thinking that a window is a window is a window. It is not a commodity item where if you’ve seen one, you’ve seen them all.


If glass was a great insulator, every window in the market today would be single pane. Unfortunately that’s not the case. In fact, it’s the extreme opposite. Heat and cold will transfer straight through glass as though it wasn’t even there. As a matter of fact, a recent study conducted by National Geographic found that 70% of the energy generated to heat and cool your home is lost through windows just like this.


Having now understood the insulating benefits of trapped air space, technology then evolved over the years to a true hermetically sealed double pane glass package. This product utilized an aluminum spacer bar with a 7/8” gap between the two panes.

Naturally, the idea caught on that perhaps “TWO panes” is twice as good as “ONE”. Nothing could be farther from the truth. The truth is 7/8” clear double pane technically does have a higher R-factor (insulation rating) than single pane, but it is so insignificant that it essentially has no impact on better insulating your home.


The next breakthrough in glass technology came when the industry introduced what is generically referred to as ‘Low E’. Low E is short for Low Emissivity. Emissivity is a term used in thermodynamics for measuring an object’s ability to either reflect or absorb radiant energy.

In the world of windows, Low E is the term used for tiny metallic particles that are embedded into the glass. These metallic particles are supposed to have a heat reflective characteristic.

However, the majority of all window companies bragging that they have Low E glass are more than likely using Hard Coat Low E. This is where TIN OXIDE (which is very cheap…think tin cans) is embedded into the glass during its molten state. The end result is a cheap process that produces cheap results. Hard Coat is also referred to as “Pyrolitic” in the industry.

90% of all Low E windows being advertised have the Hard Coat application.

Click here to learn about the most recent innovation in the evolution of glass and replacement windows.

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