Compare Low-E 180 and 272, double-pane and triple-pane glass, argon, U-factor and SHGC. Choose a glass package using ratings for the complete window.
Low-E coatings reduce radiant heat transfer through glass. They are part of an insulating glass package, alongside the panes, spacer, seals and any gas fill. A factory coating is different from a film added to an existing window; confirm compatibility before applying aftermarket film.
Choose the coating together with the complete window. Climate, orientation, shading and room use affect the choice. The same coating can have different whole-window ratings in different frames and glass constructions.
Read whole-window performance ratingsCardinal describes LoĒ-180 as a high solar gain option and LoĒ²-272 as a solar-control option. Compare the manufacturer’s data for the actual glass construction, then request the corresponding complete-window ratings.
Panes configured window examples for the United States start with double-pane Low-E 272 / clear and argon. The US catalog uses Low-E 272 over clear; the Canadian catalog uses Low-E 180 over clear. Review available alternatives in the designer or with Panes before finalizing your order.
These catalog defaults are not a recommendation for every exposure or a certification claim. Cardinal’s center-of-glass figures describe glass performance; they do not include the Panes frame, sash and other parts of the finished window.
Order replacement insulated glass · See configured windows and current pricesAn insulating glass unit uses separated panes and sealed cavities. Argon or krypton can reduce heat transfer through those cavities compared with air. Gas fill, cavity spacing, coatings and frame design all contribute to the finished product.
Compare actual double-pane and triple-pane configurations rather than assigning a generic U-factor to every two- or three-pane window. Ask about available sizes, hardware compatibility, price and whole-window ratings. Do not assume that a gas or glazing option is offered on every product.
Compare double-pane and triple-pane windows · Choose glass for single-hung or double-hung windows · Compare sliding window models and glassTell Panes and your installer where the glass will be used, including doors, sidelites, bathrooms and glass close to floors or walking surfaces. Confirm any required safety glazing for the specific opening before ordering.
Obscure glass is a privacy choice. It does not by itself establish safety, acoustic, security or impact performance. If you need a specific rating, request evidence for the complete selected assembly; a material name or pane count is not sufficient.
Explore entry-door glass designs · Send your opening requirementsRecord each opening’s frame dimensions, operating style, glass package, finish and installation method. Compare prices for equivalent specifications, then review freight, tax and installation separately. Keep the approved glass selection on the final order.
Compare awning windows and prices · Design a casement window · Plan a custom replacement window order · Specify windows for new construction| Rating | What it means | What to check |
|---|---|---|
| U-factor | Heat transfer through the complete product. Lower values mean less heat transfer. | Compare ratings in the same units for the applicable frame and glass configuration. |
| Solar heat gain coefficient (SHGC) | The fraction of solar energy admitted through the product. Lower values admit less solar heat. | Review sun exposure, shading and heating versus cooling priorities. |
| Visible transmittance (VT) | The fraction of visible light transmitted through the product. Higher values admit more daylight. | Compare daylight alongside glare, privacy and the size of the glass area. |
Ask for the applicable NFRC listing or product label. A coating name does not establish ENERGY STAR certification.
Compare whole-window U-factor first. Ask for equivalent double-pane and triple-pane options in the same frame. Consider SHGC separately: winter sun can help in some exposures, while summer overheating may call for shading or different glass.
Compare SHGC for the full window and discuss exterior shading. A lower SHGC reduces admitted solar heat, but check the daylight tradeoff using VT. Review west-facing rooms separately from shaded or north-facing rooms.
Compare whole-window VT and the actual glass area. Review finish samples, glare and nearby shading. A high-transmittance coating does not mean that every window size or frame admits the same amount of daylight.
Ask which obscure or decorative glass is compatible with your selected window or entrance. Privacy, thermal performance, safety glazing and sound control are separate requirements; confirm each in the final specification.
Reviewed October 8, 2026. Manufacturer glass data and general guidance do not replace the rating and specification for your ordered product.
Low-E means low emissivity. A coating on the glass reduces radiant heat transfer. Coatings differ in how much solar heat and visible light they admit, so compare the U-factor, SHGC and VT for the complete window.
Cardinal describes LoĒ-180 as a high solar gain coating and LoĒ²-272 as a solar-control option. Panes configured window examples use Low-E 180 over clear in Canada and Low-E 272 over clear in the US. These are starting configurations; confirm the glass and whole-window ratings for your project.
Compare the available double-pane and triple-pane options in the same window system, including whole-window ratings, price, daylight and product limitations. An extra pane alone does not establish the performance or value of your completed installation.
No. A coating name or a glass-only data sheet does not establish certification for the complete window. Request the applicable product certification and rated configuration before relying on a certification claim.