Spring is the time of renewal, and for homeowners it is the ideal time to start those renovation projects around the house.

Window upgrades provide excellent returns to property owners.

Replacing those old double glass windows with today's technologically superior versions not only yields tremendous energy savings but also a great ROI (return on investment).

Over the past decade - while we haven't been looking – window technology has improved significantly.

Windows today come with energy ratings as well as measurements like 'visible transmittance', and 'condensation resistance'.

Centra Windows is a BC-based company with 29 years of experience in the home building materials industry. The Langley based operation is one the country's largest window manufacturers.

All finished products are made in Canada.

When you visit any one of their numerous showrooms across BC, the company's Certified Energy Evaluators provide a thorough explanation of the best options for upgrading your windows to improve their energy efficiency.

Here are explanations to some of the criteria used for Energy Star windows.

AL - the Air Leakage rating expresses the cubic feet of air which passes through a square foot of window area by way of leaks or cracks in the window assembly. The lower the AL number, the less air will pass through the window assembly.

CR - Condensation Resistance is expressed in a number from 0 to 100 to indicate the ability of the window to potentially resist the formation of condensation on the interior surface. The higher the CR number, the better the product will be at resisting interior condensation.

Energy Star - A rating which describes energy efficiency performance for appliances, windows, and even homes.

SHGC - the Solar Heat Gain Coefficient ranges from 0 to 1 and indicates how well a window blocks heat caused by sunlight. The lower the SHGC, the less solar heat transmits through the window; the higher the SHGC, the more solar heat will transmit through the window.

VT - Visible Transmittance also ranges from 0 to 1 and indicates the amount of total visible light that the window will transmit. The higher the VT, the more visible light will pass through the window.

 To speak with a Centra representative on your windows, doors, siding, or furnace or home heating system, call  604-882-5010 or go to www.centra.ca.