Our Windows

Operating Types of Windows

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When you select a window, there are numerous operating types to consider. Traditional operable window types include the projected or hinged types such as Casement and Awning, and the sliding types such as Single-Hung and Slider. In addition, the current window market includes Storm Windows, Sliding and Swinging Patio Doors, Skylights and Roof-Mounted (i.e., sloping) Windows, and window systems that can be added to a house to create Bay or Bow Windows, Miniature Greenhouses, or Full Sun Rooms.

Benefits of Energy Efficient Windows

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Cooling and Heating Season Savings

Low-E coatings, gas-fills, and insulating spacers and frames can significantly reduce winter heat loss and summer heat gain.

Improved Daylight and View

New glazings with low-solar-gain low-E coatings can reduce solar heat gain significantly with a minimal loss of visible light (compared to older tints and films).

Improved Comfort

In summer and winter occupant comfort is increased; window temperatures are more moderate and there are fewer cold drafts. Discomfort from strong summer sunlight is reduced.

Reduced Condensation

Frame and glazing materials that resist heat conduction do not become cold and this results in less condensation.

Reduced Fading

Coatings on glass or plastic films within the window assembly can significantly reduce the ultraviolet (UV) and other solar radiation which causes fading of fabrics and furnishings.

Lower Mechanical Equpiment Costs

Using windows that significantly reduce solar heat gain means that cooling equipment costs may be reduced.

Properties of Energy Efficient Windows

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U-Factor

The rate of heat loss is indicated in terms of the U-factor (U-value) of a window assembly. The insulating value is indicated by the R-value which is the inverse of the U-value. The lower the U-factor, the greater a window's resistance to heat flow and the better its insulating value. U=U-factor in Btu/hr-sf-°F.

Visible Transmittance (VT)

The visible transmittance (VT) is an optical property that indicates the amount of visible light transmitted. The NFRC's VT is a whole window rating and includes the impact of the frame which does not transmit any visible light. While VT theoretically varies between 0 and 1, most values are between 0.3 and 0.8. The higher the VT, the more light is transmitted. A high VT is desirable to maximize daylight. VT=Visible Transmittance in fraction of incident visible radiation.

Solar Heat Gain Coefficient (SHGC)

The SHGC is the fraction of incident solar radiation admitted through a window. SHGC is expressed as a number between 0 and 1. The lower a window's solar heat gain coefficient, the less solar heat it transmits. Use a computer program such as RESFEN to understand heating and cooling tradeoffs. SHGC=Solar Heat Gain Coefficient in fraction of incident solar angle.

Air Leakage (AL)

Heat loss and gain occur by infiltration through cracks in the window assembly. Air leakage is expressed in cubic feet of air passing through a square foot of window area. The lower the AL, the less air will pass through cracks in the assembly. While many think that AL is extremely important, it is not as important as U-factor and SHGC. AL=Air Leakage in cfm/sf.

Window Performance Ratings

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Aluminum with Thermal Break

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Aluminum window frames are light, strong, durable, and easily extruded into the complex shapes required for window parts. Aluminum frames are available in anodized and factory-baked enamel finishes that are extremely durable and low-maintenance.

The biggest disadvantage of aluminum as a window frame material is its high thermal conductance. It readily conducts heat, greatly raising the overall of a window unit. In cold climates, a simple aluminum frame can easily become cold enough to condense moisture or frost on the inside surfaces of window frames. Even more than the problem of heat loss, the condensation problem has spurred development of better insulating aluminum frames.

The most common solution to the heat conduction problem of aluminum frames is to provide a "thermal break" by splitting the frame components into interior and exterior pieces and use a less conductive material to join them. Current technology with standard thermal breaks has decreased aluminum frame U-factors (heat loss rate) from roughly 2.0 to about 1.0 Btu/hr-sq. ft-F. In hot climates, where solar gain is often more important than conductive heat transfer, improving the insulating value of the frame can be much less important than using a higher-performance glazing system.

Glazing Single Glazed Clear Single Glazed with Broze/Gray Tint Double Glazed Clear Double Glzed with Bronze/Gray Tint Double Glazed with High Performance Tint
U-Factor 1.00 1.00 .63 .63 .63
SHGC .70 .59 .62 .52 .43
VT .70 .53 .63 .48 .54
Glazing Double Glazed with High Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas
U-Factor .50 .48 .47 N/A N/A
SHGC .58 .48 .33 N/A N/A
VT .58 .60 .55 N/A N/A
Note: The data presented here is an average of similar (but not identical) products from several manufacturers. Specific products will have performance properties slightly higher or lower. Users are encouraged to check with specific manufacturers for exact performance properties.

Wood Windows

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The traditional window frame material is wood, because of its availability and ease of milling into the complex shapes required to make windows. Wood is favored in many residential applications because of its appearance and traditional place in house design. From a thermal point of view, wood-framed windows perform well with frame in the range of 0.3 to 0.5 Btu/hr-sq. ft-F. Wood is not intrinsically the most durable window frame material, because of its susceptibility to rot, but well-built and well-maintained wood windows can have a very long life. Paint protects the exterior surface and allows an easy change in color schemes.

Glazing Single Glazed Clear Single Glazed with Broze/Gray Tint Double Glazed Clear Double Glzed with Bronze/Gray Tint Double Glazed with High Performance Tint
U-Factor .84 .84 .49 .49 .49
SHGC .64 .54 .56 .47 .39
VT .65 .49 .59 .44 .50
Glazing Double Glazed with High Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas
U-Factor .37 .35 .34 N/A N/A
SHGC .53 .44 .30 N/A N/A
VT .54 .56 .51 N/A N/A
Note: The data presented here is an average of similar (but not identical) products from several manufacturers. Specific products will have performance properties slightly higher or lower. Users are encouraged to check with specific manufacturers for exact performance properties.

Vinyl Windows

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Plastics are relative newcomers as window frame materials in North America. Vinyl, also known as (PVC), is a very versatile plastic with good insulating value. Vinyl window frames do not require painting and have good moisture resistance. Because the color goes all the way through, there is no finish coat that can be damaged or deteriorate over time -- the surface is therefore intenance-free. Some vinyl window manufacturers are now offering surface treatments like laminates (wood veneer, paintable/stainable, maintenance free) and coatings. These products increase color selection and surface appearance options. Recent advances have improved dimensional stability and resistance to degradation from sunlight and temperature extremes.

Glazing Single Glazed Clear Single Glazed with Broze/Gray Tint Double Glazed Clear Double Glzed with Bronze/Gray Tint Double Glazed with High Performance Tint
U-Factor .84 .84 .49 .49 .49
SHGC .64 .54 .56 .47 .39
VT .65 .49 .59 .44 .50
Glazing Double Glazed with High Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas
U-Factor .37 .35 .34 N/A N/A
SHGC .53 .44 .30 N/A N/A
VT .54 .56 .51 N/A N/A
Note: The data presented here is an average of similar (but not identical) products from several manufacturers. Specific products will have performance properties slightly higher or lower. Users are encouraged to check with specific manufacturers for exact performance properties.

Hybrid/Composite

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Hybrid

Manufacturers are increasingly turning to hybrid frame designs that use two or more frame materials to produce a complete window system. The wood industry has long built vinyl- and aluminum-clad windows to reduce exterior maintenance needs. Vinyl manufacturers and others offer interior wood veneers to produce the finish and appearance that many homeowners desire. Split-sash designs may have an interior wood element bonded to an exterior fiberglass element. We are likely to see an ever-increasing selection of such hybrid designs as manufacturers continue to try to provide better-performing products at lower cost. It may be important for a homeowner to learn about these materials from the perspective of maintenance requirements and options for interior finishes. However, it becomes increasingly difficult to estimate the thermal properties of such a frame from simple inspection. The best source of information is an that provides the thermal properties of the overall window.

Composite

Most people are familiar with composite wood products, such as particle board and laminated strand lumber, in which wood particles and resins are compressed to form a strong composite material. The wood window industry has now taken this a step further by creating a new generation of wood/polymer composites that are extruded into a series of lineal shapes for window frame and sash members. These composites are very stable, and have the same or better structural and thermal properties as conventional wood, with better moisture resistance and more decay resistance. They can be textured and stained or painted much like wood. They were initially used in critical elements, such as window sills and thresholds in sliding patio doors, but are now being used for entire window units. This approach has the added environmental advantage of reusing a volume of sawdust and wood scrap that would otherwise be discarded.

Glazing Single Glazed Clear Single Glazed with Broze/Gray Tint Double Glazed Clear Double Glzed with Bronze/Gray Tint Double Glazed with High Performance Tint
U-Factor .84 .84 .49 .49 .49
SHGC .64 .54 .56 .47 .39
VT .65 .49 .59 .44 .50
Glazing Double Glazed with High Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas
U-Factor .37 .35 .34 N/A N/A
SHGC .53 .44 .30 N/A N/A
VT .54 .56 .51 N/A N/A
Note: The data presented here is an average of similar (but not identical) products from several manufacturers. Specific products will have performance properties slightly higher or lower. Users are encouraged to check with specific manufacturers for exact performance properties.

Insulated Vinyl

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Insulated vinyl frames are identical in most of their characteristics to standard vinyl frames. Vinyl window frames do not require painting and have good moisture resistance. Because the color goes all the way through, there is no finish coat that can be damaged or deteriorate over time -- the surface is therefore maintenance-free. Recent advances have improved dimensional stability and resistance to degradation from sunlight and temperature extremes.

The major difference between insulated vinyl and standard vinyl frames is improved thermal performance. In insulated vinyl frames, the hollow cavities of the frame are filled with insulation making them thermally superior to standard vinyl and wood frames. Usually these high performance frames are used with high performance glazings.

Glazing Single Glazed Clear Single Glazed with Broze/Gray Tint Double Glazed Clear Double Glzed with Bronze/Gray Tint Double Glazed with High Performance Tint
U-Factor     .44 .44 .44
SHGC     .60 .49 .41
VT     .60 .49 .41
Glazing Double Glazed with High Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas
U-Factor .29 .27 .26 .18 .18
SHGC .56 .46 .31 .40 .26
VT .59 .60 .55 .50 .43
Note: The data presented here is an average of similar (but not identical) products from several manufacturers. Specific products will have performance properties slightly higher or lower. Users are encouraged to check with specific manufacturers for exact performance properties.

Fiberglass Windows

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Window frames can be made of glass-fiber-reinforced polyester, or fiberglass, which is extruded into lineal forms and then assembled into windows. These frames are dimensionally stable and have air cavities (similar to vinyl). When the cavities are filled with insulation, fiberglass frames have thermal performance superior to wood or vinyl (similar to insulated vinyl frames). Because the material is stronger than vinyl, it can have smaller cross-sectional shapes and thus less area. Another polymer-based approach is to use extruded engineered thermoplastics, another family of plastics used extensively in automobiles and appliances. Like fiberglass, they have some structural and other advantages over vinyl.

Usually these high performance frames are used with high performance glazings. The window properties shown below assume fiberglass frames that have cavities filled with insulation.

Glazing Single Glazed Clear Single Glazed with Broze/Gray Tint Double Glazed Clear Double Glzed with Bronze/Gray Tint Double Glazed with High Performance Tint
U-Factor     .44 .44 .44
SHGC     .60 .49 .41
VT     .63 .48 .54
Glazing Double Glazed with High Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Double Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Moderate Solar-Gain Low-E, Argon/Krypton Gas Triple Glazed with Low Solar-Gain Low-E, Argon/Krypton Gas
U-Factor .29 .27 .26 .18 .18
SHGC .56 .46 .31 .40 .26
VT .59 .60 .55 .50 .43
Note: The data presented here is an average of similar (but not identical) products from several manufacturers. Specific products will have performance properties slightly higher or lower. Users are encouraged to check with specific manufacturers for exact performance properties.

Our Installation Process

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We do not just install windows. We got the distance.
1) We start by completely removing your old windows by cutting the siding back and exposing the nail fin. This is a crucial step in long-term performance of your new windows. We then completely remove your old window nail fin and all.
2) We then cut out the old drywall or interior trim.
3) Now we clean the opening and prepare it for a new window.
4) We install leveling blocks to insure your new window is square and plumb. This also helps with the install of the new interior trim assuring the same spacing or reveal around the window.
5) After the leveling blocks are installed we install the new window into the opening and secure it with screws checking our level for an accurate setting.
6) We then install flange or fin tape around the window to insure against leakage or air drafts.
7) Next comes the head flashing to divert rainfall and water that runs down the siding away from the window.
8) Finally we install new exterior trim usually cedar, primed and ready for paint. The window is then caulked and the outside is complete. This is the professional installation method. Using this method your new windows will be trouble free and will not need to be replaced again for 50 or so years when the next best window comes out.
9) Moving on to the interior trim. Remember we already installed the leveling blocks in the window so we will use these to place a new interior trim on to assure a proper fit and reveal. The trim is cut to size for each window. First we cut the bottom trim and then the top and side trim. We install them with a 2 nail and/or staple gun. Once the liners are completed we install the casing usually 2 molding and complete the inside.
*These steps are an example of a full window replacement and the only process we would recommend when removing your old window. If youre old interior trim is in good shape it may not need to be replaced. If you have any questions about proper window installation procedures please feel free to call and talk with one of our window technicians. Thank you for your interest in Clear Image Glass.