We weigh in on the different materials of a building’s exterior components, whether it’s windows, roofing or facades.
When it comes to building exteriors, a lot of attention is naturally given to the design. But one detail that slips by the casual observer is the material components of a building’s exterior. The materials used in the manufacture of the windows, roofing and facades play an important role in meeting the structural or energy objectives of the builder.
Wood Frames
Wood windows are warm, traditional and aesthetically pleasing. For years, wood has been a readily available window substrate, and the most common choice for homes. It could be painted a solid color or stained and sealed to show off the wood grain. Wood is also strong and easy to work with, and complements many forms of architecture.
Because it is a good insulator, wood does not become cold like metal and glass. But it also expands and contracts in response to weather conditions. Wood windows can be painted on the exterior or clad with aluminum or PVC profiles for better weathering and reduced maintenance.
Aluminum Frames
Aluminum windows are more durable than wood, and are thinner, lighter, and easier to handle. Aluminum frames are easy to maintain and are sometimes less expensive than other frame options. But aluminum is a poor insulator and in cold weather loses more heat to the exterior than wood. Most recent aluminum windows are manufactured with a thermal break, a vinyl or rubber strip that separates the exterior and interior aluminum parts of the window. The thermal break reduces the movement of cold air from the outside to the inside of the building.
PVC Frames
PVC windows are relatively new compared to wood and metal frames. These windows are extruded from high impact resistant polyvinyl chloride (PVC). PVC windows have excellent weathering characteristics, are almost maintenance-free and have excellent resistance to heat loss. Originally used primarily in renovation because PVC lends itself to non-standard size production, PVC windows are rapidly increasing in the new construction market as well. PVC is available in several extruded colours. Special painted coatings have been developed to expand the range of colors available.
Composite Frames
Composites made from wood fibers, wood scraps, and ground up knots, are bonded together in a resin and shaped to replace window parts traditionally made of solid wood. Structurally, composite materials are equal to or superior to solid wood. They have two distinct advantages: a lower initial cost and they are less prone to warping and shrinking. Composite materials cannot be stained and usually are pre-painted during the manufacturing process. Due to their recycled nature composite frames are the ideal ‘green’ option as they make the most of the available resources, thus saving trees.
Thatch
Probably the oldest form of roofing, thatch is also eye catching, sustainable and quite durable. If installed correctly thatch can last anywhere between 15 to 20 years in good condition. The type of thatch material varies according to geographical location so the material used will generally suit the climate of the area. Being a naturally insulating material, thatch is able to insulate your home without the need for additional insulating materials such as natural or synthetic wools. However the main problems with thatch are the high cost of installation and the constant need for maintenance. It is also more prone to rot and infestation.
Metal roofing
Metal roofs are resistant to extreme weather conditions. Available in two types, panels and shingles, metal roofs can come in aluminum, copper, stainless steel and zinc. Metal roofing is durable, lasts longer than asphalt or wood, and offers high solar reflectance. Metal roofs are becoming increasingly viable, as metal shingles are low maintenance, lightweight and more environmentally friendly. Metal shingles typically simulate traditional roof coverings, such as wood shakes, shingles, slate and tile. Aside from its longevity, metal shingles are much lighter than most materials and very resistance to adverse weather.
However, installation can be tricky and requires a contractor with experience installing a metal roof. As a metal roof starts to lose its shine, repainting is an option as long as the roof’s structural integrity is in good shape.
Clay Tile/Shingles
While brittle and heavy, clay tiles can last a long time and are very fire resistant. Clay tiles are very heavy, requiring additional roof framing, but they are non-combustible and extremely durable. Clay roofing tiles can come in lighter colours, which adhere to the cool roof standards and can reflect well over 50% of the sun’s solar energy. Genuine flat, ribbed or scalloped clay tiles are extremely durable but also very heavy, and must be installed by a professional.
Concrete Flat Roof or Tiles
The most common type of roof found in Indian cities; flat concrete roofs require a great deal of maintenance. They need to kept water tight and cleaned regularly to prevent leaves and debris from clogging the drain. The sun will gradually cause the roof to degrade, as flat roofs located in environments with hot and cold extremes are more vulnerable to damage. Flat roofs are typically less expensive to install than sloped roofs. Concrete tiles are very versatile and come in many different hues, shapes, textures and styles.
Compiled By
Anand Mishra
MD – Trimurty
