Volume 10. Issue 7 . July 2016 Rs. 25/-
THE
INSIDE TRACK CONNECTING THE DESIGN COMMUNITY Now view our web edition at www.theinsidetrack.in
Cover Story
W
hen 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.
Material Matters
We weigh in on the different materials of a building’s exterior components, whether it’s windows, roofing or facades. BY ALYSSA LOBO 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
Wood frames: Wood is a good insulator as it does not become cold like metal and glass
The most common materials used in window frames are aluminium, PVC, fiberglass, or some combination of these materials. Here we explore the pros and cons of various materials used in the production of these exterior components and the ideal conditions for their use. 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 colour 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.
aluminium or PVC profiles for better weathering and reduced maintenance. Aluminium Frames Aluminium windows are more durable than wood, and are thinner, lighter, and easier to handle. Aluminium frames are easy to maintain and are sometimes less expensive than other frame options. But aluminium is a poor insulator and in cold weather loses more heat to the exterior than wood. Most recent aluminium windows are manufactured with a thermal break, a vinyl or rubber strip that separates the exterior and interior aluminium parts of the window. The thermal break reduces the movement of cold air from the outside to the inside of the building.
Most commercial applications still specify aluminium windows. Aluminium is not recommended in beach homes or houses close to the sea, for while the material is water resistant, it can suffer corrosion from salt water and salt air. The corrosion affects hardware operation and frame performance. 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 i t s e l f t o n o n - s t a n d a rd s i z e 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 colours available. Fibreglass Frames Fibreglass windows are the latest window products to be developed. The shapes are formed by a special technique called pultrusion, whereby
the glass fibres are pulled through dyes rather than pushed through an extruder (as PVC is extruded). Fiberglass and PVC lineals look similar; however fiberglass is much more rigid than PVC. Fiberglass has steadily grown in popularity over the years as a low-maintenance alternative to traditional wood frames.
Veka PVC windows: PVC windows have excellent weathering characteristics
Composite Frames Composites made from wood fibres, wood scraps, and ground up knots, are bonded together in a resin and shaped to replace window parts traditionally made of solid wood. continued on page 2
Aluminium frames are not recommended in houses close to the sea as it can suffer corrosion from salt water and air