When the design, form and shape of the window are rounded and very stylish, the builder will tend to make steel frame windows. The steel window design can provide a variety of curved shapes, rustic appearance and security bars on the interior and/or exterior of the window, which cannot be easily duplicated in aluminum window frames.
Aluminum windows generally are lightweight and easier to operate. But, due to the nature of the material, aluminum windows are not as strong and require wider and thicker sectional shapes to be as strong as the steel alternative. In general, if security bars are needed, aluminum windows will require secondary security attached to the exterior wall around the window rather than directly to the frame of the window.
A typical design flaw in windows becomes apparent when rainwater that strikes the exterior of the window is able to run down the exterior of the window and then drip into the interior side of the window and finally into the room. Wind-driven rain can accentuate the problem, and mosquito screens on the exterior do not prevent the penetration of rainwater.
Some of the newer aluminum window designs include well engineering tracks at the bottom of the windows that help prevent the penetration of rainwater inside the room. The lower track allows for water to drain through small weeping holes that prevent the accumulation of rainwater in the track, which could drain back into the house. Sometimes roof overhangs or awnings will also help protect the windows by minimizing the amount of rain that strikes the face of the window. This should all be considered when designing the window location, the type and care of installation.
The care of installation can be affected by the opening where the window is installed. There are times the “sill” or base of the window has not been carefully established as level or is inclined outward to promote drainage away from the window. Sloppy setup of this sill cannot be remedied by extra silicone along the joint between the window and base, since the silicone will deteriorate with time and eventually lead to leakage to the interior of the window and damage to the paint or frame. It could even cause masonry efflorescence, which is commonly called salitre.
Doors can have similar problems with rainwater striking the exterior of the door. However, depending on the threshold of the door, rainwater can drain towards the interior of house. Small weather strips along the base of the door that can also act as door sweeps can help redirect the rainwater away from the base of the door and impede rainwater from running under the door.
Doors — whether steel, aluminum or wood — need to be installed correctly, which includes hanging it vertically in the sense that door will hold its position and not open or close by itself. When hung correctly, the door will have an even space between it and the frame around the sides, top and bottom. Uneven spaces around the door could indicate simply a sloppy installation but they could also indicate structural movement in the walls around the doorway resulting from graver problems in the soil conditions, foundations or structure.