Metal Replacement Windows 

Types of Metal Windows

Metal windows, both steel and aluminum, like other types, have their advantages and disadvantages. Metal windows are mostly used by commercial customers. They are strong and as such offer good durability and longevity at a reasonable cost. This combined with their narrow profile is why many architects like them. Lets start with steel windows.

Steel Windows

While steel windows offer some aesthetic appeal, and long-term life expectancy, they do have some major drawbacks. Steel has high thermal conductivity, which means touching the windows on a cold winter day can be unpleasant. Metal windows are long lived but are subject to corrosion, warping and drafts. Remember the conductivity of a wood window is 1.2, and the lower the number the better. The government rates steel windows at about 350! The other problem with all metal windows is that metal against metal doesn't seal real well... they're drafty. The major styles of steel windows are steel casements and double hung windows.

So the major plus for steel windows is strength and therefore longevity. Over the long term this could also produce some savings. The problem with their savings is they give them back in terms of fuel loss. Steel is a high conductor of heat and cold. They will get as cold or hot inside as they are outside. Not good in today's world of high-energy costs.
Okay enough of steel windows, lets take a look at aluminum windows

Aluminum Windows

Aluminum windows have much in common with steel windows. They last a long time because they are strong. Not as strong as steel windows, but strong. As a metal window they are also drafty. They come in double hung style, but vastly more popular in aluminum windows is the aluminum slider. Some brands may call it a glider.

Like their steel cousins they were popular about 50 years ago when oil was $.17 per gallon. They were popular because they were strong and cheap and fuel efficiency was not really an issue. When it comes to conductivity, remember wood was 1.2, steel about 350, and aluminum is ...fasten your seat belt, 1,500. Wow! Is it any wonder why they put beer and soda in aluminum cans, it gets cold fast. I've been in many homes over the years with aluminum windows with frost and ice on the inside. You see metal windows sweat, and then the condensation freezes. This is also why metal windows many times get mold and mildew. One thing to watch out for is the "thermal break". The theory is that the inside of the sandwich will not pick up the cold or heat from the outside because of the thermal break. It doesn't really work; it just slows the process down a bit. The truth is that it is not a thermal break; rather it is a thermal barrier.

So much for metal windows, move on to composite windows.