Getting Started…

Deciding to purchase replacement windows for your home is a big deal. You might want to get yourself prepared for the meeting with our company’s representative. It is important that you educate yourself as much as possible, as it is important for Canglow representative to answer all of your questions and inform you about the product to the fullest extent. So, here is some simple terminology with reference to the picture that you might find useful in your preparations.

  1. Strong fusion-welded frame and sash corners keep cold air out.
  2. Multi-chambered design increases insulation value, adds strength, improves drainage and prevents condensation.
  3. Triple co-extruded weather-strip sealing for added insulation value.
  4. 90° sash opening lets you clean easily from inside.
  5. Interior glazing system with flexible sash seal eliminates leaks.
  6. Drainage channels on exterior sash, not visible from inside.
  7. Easy-clean, removable overlap internal screen.
  8. Multi-point locking system provides additional security.
  9. 3/4″ double-strength glass for optimum insulation efficiency.
  10. Dual Arm Truth MaximTM system hardware for effortless operation.

Materials used in Energy Star qualified windows sold by Canglow: Double and triple-pane windows do not reduce heat loss because of additional glass. They are designed with a sealed air space, usually half an inch wide, which works as an additional insulator. This space restricts air movement, slowing down heat loss through windows.

Low-e (low- emissivity) windows have a clear coating on the glass to keep heat outside during the summer and heat inside during the winter. This is a virtually invisible coating of semi-conductor or metal oxide film that is applied directly to the glass or on plastic film between the two panes. Low-e windows also block a portion of the ultraviolet light that contributes to the fading of carpets, drapes and furniture.

Low-e coatings come in two varieties – hard coat or soft coat. Soft coats or sputter coats, primarily silver oxide, are the most effective at reflecting heat and generally insulate better than hard coats. By reducing heat build-up in the summer, soft coat can reduce the use of air conditioning. On the other hand, hard coats allow more solar heat to pass through the window, which can reduce space heating requirements on sunny winter days. Windows manufactured with low-e films typically cost about 10 per cent more than regular double glazed windows, but they will reduce energy loss by as much as 30 % to 50 %. The energy savings alone should pay for that higher cost in less than 10 years.

Window frame construction and materials can have a big effect on energy performance, required maintenance and life span of windows.

  • Vinyl frames – can offer improved thermal performance and freedom from maintenance.
  • Wood frames – have a good strength, insulating value and life span, but require maintenance for continued protection from the weather.

When comparing two windows of the same size, a fixed picture window will always perform better than a window that opens. This is primarily due to the air leaks that occur along the opening edges of the window.

Other components to look for in ENERGY STAR qualified windows:

  • Windows and doors are ENERGY STAR qualified by their U-value or their Energy Rating (ER).
  • U-values indicate how well a window keeps heat in your home. A low U-value means less heat is transferred through the window. It is defined as a reciprocal of the R-value (U= 1 / R), where the R-value measures a windows resistance to heat flow.
  • Energy Ratings (ER) provide a measure of a window’s overall energy performance. ER measures heat gain and loss through the window frame and the glass. A higher ER number means the window generally will lose less heat.


Ensure your ENERGY STAR labelled windows are installed by a qualified window professional. Even a high performance window will perform poorly if installed improperly.

Patio doors perform much like an insulated glass window unit. As the glass area is large, always use as many thermal performance features as possible, such as low-e coating, gas fills and thermal spacers, to increase the insulation value of the unit. ENERGY STAR qualified doors have minimum energy ratings that specify their insulating and air leakage performance. They often incorporate low-e coatings, argon gas fill and better air tightness, all of which contribute to reduced heat loss.

Planning Tips…

If your budget doesn’t allow you to change all your windows at once, plan to complete your window purchase in distinct phases. Some suggestions are:

1) Install south and west facing windows first. These windows generally have the largest impact on your comfort and energy savings performance.

2) Install new windows where your family spends most of their time. Once you begin to enjoy the comfort, aesthetics and savings, you will see the benefit of purchasing the remaining windows.

Installing new windows can decrease the size of the heating system you need to effectively heat your home. We recommend changing your windows before installing a new furnace or boiler. In many cases, you will be able to install a smaller heating system, which lowers the heating system cost and prevents purchasing an oversized furnace.

We hope this information had given you insight into your new project. Our team of professionals is dedicated to superior customer service and will gladly give you a free, no obligation estimate and answer all of your questions. If your windows or doors need to be replaced, give us a call to schedule an appointment.