Windows and Doors

DEFINITION

CONSIDERATIONS

COMMERCIAL STATUS

IMPLEMENTATION ISSUES

GUIDELINES

1. Windows
2. Doors

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CSI Numbers

Division 8 – Doors & Windows

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DEFINITION:

Composite materials use stable, durable materials, some of which are byproducts. Fingerjointed windows use small pieces of wood reducing the impact on large clear grained wood sources. Recycled windows can mean reuse of salvaged windows or windows of recycled content.

Recycled/reconstituted doors are typically molded hardboard materials. Domestic hardwood veneers use a stable resource and assist our national economy. Some hardwood veneers such as luaun are from tropical mahogany trees. Domestic hardwood panel doors use wood types which are a stable resource in our economy. The panel style reduces the need for potentially harmful adhesives. Recycled doors are reused doors salvaged from earlier projects.

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CONSIDERATIONS:

Windows and doors are currently highly engineered in order to optimize energy performances. Windows and doors have significant roles in the energy profile of a home. Frame material issues, although important as part of an overall environmentally responsible approach, play only a small role due to their small size/area. Performance of these products is important in durability and maintenance, as well as energy.

Modern composite products are easy to care for, and their thermal performance is superior to wood. One door manufacturer has introduced recycled-content jambs using recycled plastic and cedar byproducts. Molded hardboard doors have become the preferred interior door and are a good use of lumber mill waste shavings.

The reuse of existing materials is the most resourceful building material option. Make certain that quality and durability are not compromised.

Make certain seals and gaskets are in good condition when selecting recycled windows.

Any windows using fingerjointed materials will need to be painted for aesthetic reasons. It is best to have the windows factory primed where the painting is done in controlled conditions.

	Commercial Status				Implementation Issues
	T E C H N O L O G Y	S U P P L I E R S	C O S T		F I N A N C I N G	A C C E P T A N C E	R E G U L A T O R Y
Composite
Fingerjointed
Recycled
Recycled/ Reconstituted
Domestic Hardwood Veneer
Domestic Hardwood Panel

	Satisfactory
	Satisfactory in most conditions
	Satisfactory in Limited Conditions
	Unsatisfactory or Difficult

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COMMERCIAL STATUS

TECHNOLOGY:

More composite window products can be expected soon. Important strides have been made in UV resistance. Other door and window products listed here use mature technologies.

SUPPLIERS:

Suppliers of recycled windows and doors can not guarantee that they have appropriate products for a specific project.

The range of composite window products is limited locally.

Hardwood veneer doors are less common than recycled/reconstituted-content doors and hardwood panel doors may have to be ordered.

COST:

Panel doors are costly. Recycled windows and doors may entail considerable labor expense to prepare for use.

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IMPLEMENTATION ISSUES

FINANCING:

Recycled materials (reused) may be questioned unless they are shown to be of high quality.

PUBLIC ACCEPTANCE:

Awareness of composite products is not high. Once convinced of maintenance-free qualities and durability, buyers should find them attractive. Recycled (reused) materials must be high quality and/or of architectural significance to gain acceptance.

REGULATORY:

Windows must be tested and certified and have air infiltration qualities of less than 0.50 CFM per lineal foot of crack. New window suppliers will offer certified test data to satisfy these requirements. This information can not be provided for reused windows, thereby limiting the applicability of reused windows.

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GUIDELINES

Standard practices pertain to installing the listed window and door options.

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Windows

We all love lots of windows. We love the natural light, the views, and the fresh air we get from them. But nowadays there are so many kinds of windows available, it’s hard to make a choice. We want windows to be attractive, let in plenty of light, and be energy-efficient. We don’t want them to feel drafty or have condensation problems. And we want all this for an affordable price. Here are some questions commonly asked about windows which may help you make a smart choice.

Perhaps you live in an older house and often feel uncomfortable near the windows. Should you replace them or add storm windows? Replacing windows or adding storm windows is costly. Try these measures to improve comfort and reduce energy bills before you decide whether to purchase new windows. Caulk around all trim and stationary parts and weather-strip the moveable parts, to cut down on air leaks. Install insulated drapes or shades to reduce heat loss in winter, and install solar screens or awnings to reduce solar heat gain in summer. If you are having a problem with condensation on the inside of the glass in cold weather, try to reduce indoor sources of moisture. Install exhaust fans which vent to the outside in bathrooms, the laundry and kitchen.

Let’s say you’re building a new house and the price your builder quoted for double pane insulated windows is a lot higher than single pane. Are double pane windows worth the price?

A typical window is almost like a hole in the wall. Modern window technology combines many features that go a long way to overcome the “hole effect”, but at a price. If you know what a given feature can do for you, what it will cost you, and whether there is a cheaper measure to achieve the same result, then you can make an informed decision.

Most people get double pane windows because they think they will save them money on their heating and cooling bills. Yes, they will reduce heat loss, and therefore save on winter bills, but since we usually have mild winters in Central Texas, this potential for savings is small.

A standard double pane helps even less in summer. However, a double pane window with a special coating applied to it will greatly reduce heat gain from the hot summer sun. This coating is called low-e (short for emissivity). To work well in the south, it must be applied to the outside surface of the inside pane of glass. In the north the low-e coat is applied to the inside surface of the outside glass to keep heat inside. Be sure an uninformed salesperson doesn’t order the wrong kind! Double pane windows also reduce noise and the incidence of condensation. The seals on double pane windows have improved over the past few years, so failure of the seals is less likely. However, it does make sense to compare warranties carefully.

Besides checking the warranty, is there any other way you can compare one window brand with another? Yes. Look for the NFRC label. That stands for the National Fenestration Rating Council. (Fenestration is the architectural term for windows.) First, look at the U-Factor, which serves as a good measure of heat loss in winter. The lower the U-factor, the better. The NFRC rating considers the whole window as a unit, including glazing, the sealing method and the frame material. Next, look at the Solar Heat Gain Coefficient . In a hot climate, the lower the better. Finally, look at the Visible Transmittance. This number should be as high as possible. In summary, look for the best possible combination of numbers–the most light for the least solar gain and the least heat loss.

Don’t skimp on your window budget. A high quality window has so many benefits–lower energy bills, less maintenance, reduced fading of furniture and carpets, improved security, beauty and comfort–it pays to make a good window investment.

1.0 Windows

Windows are distinguished in two areas – glazing system and window style.

1.1 Glazing System

Single pane, double glazed, triple glazed, low-E, gas filled, etc. determine the R-value and light transmission characteristics of the window.

Glazing systems can be selected according to their placement and orientation of the house. For example, a west facing window that would experience heat gain in the summer could use a heat-rejecting glazing such as “southern” Low-E. The embodied energy in this glazing could be paid back quickly in cooling cost savings.

To decide whether a high R-value window is worth the added expense, conduct and compare heat and cooling load calculations of the building for the windows under consideration. The Energy Star Program can provide this analysis to enrolled building professionals of the Green Builder/Energy Star Programs.

1.2 Window style

Refers to double hung, casement, awning, etc. indicating the operating characteristics of the window.

Some window styles are more energy-efficient than others. For example, a casement window will close more tightly than a double hung or slider window. Check manufacturers data for infiltration ratings as well as R-value.

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2.0 Doors

Interior doors should have adequate undercut to maintain balance in the HVAC system. Be sure the airspace from the undercut is still sufficient after carpeting has been laid since the carpenter will have hung the doors earlier and may not know the thickness of the pad and carpet.

Exterior doors with magnetic seals will offer superior air infiltration benefits.