Enhancing the Envelope
Oct 1, 2005 12:00 PM, By Mike Kennedy
With energy prices escalating, schools and universities have enormous incentive to control heating and cooling costs. And, as concerns about campus security and student safety continue to be paramount, education administrators have a duty to make sure their facilities are protected from intruders, vandals or other criminals. At the same time, school facility managers must stay focused on their core mission: providing high-quality learning environments.
One step that can be taken to ensure that facilities are secure, energy-efficient spaces that are conducive to learning is to have properly functioning, well-maintained doors and windows. Properly installed doors and windows can prevent unwanted people from entering a building; they also can keep out unwanted natural elements — cold, heat, rain, snow and noise. Well-placed windows can provide the right amount of natural light that can enhance student performance, as well as reduce the reliance on artificial light.
Daylighting
Since studies have indicated daylighting in classrooms can enhance student performance, many educators and designers have placed greater emphasis on providing learning spaces with windows that allow sunlight to permeate classrooms. But school planners should be aware that just adding more windows to a classroom without careful design could be counterproductive.
“Proper daylighting designs use diffused outdoor light rather than direct sunlight,” states the Division of the California State Architect's Sustainable Schools Resource. “Direct sunlight creates glare and can detract from visual comfort.”
The resource guide recommends various types of windows such as skylights and clerestories for bringing daylight into educational spaces.
The location of windows also is critical.
“Large windows can be located on the north side of the building, or on the top of the building where the light has the opportunity to reflect into the room rather than enter directly,” the resource guide says. “Light can be brought in through the south side of the building using various daylighting techniques that block the direct sunlight from entering the building.”
To maximize energy savings through daylighting, window systems should be integrated to work with electrical lighting systems, the guide says. Lighting sensors and automatic dimmers can be installed to adjust the electric lighting level based on the amount of daylight entering the room.
Leakproof entries
A key to optimizing the energy efficiency of a facility is to guard against leaks. Leaks can occur through roofs or walls, but the most likely site to find leaks in a building is in and around door and window systems.
“Water leaks are a particular concern not just because of their resulting deterioration of building materials, but because of mold contamination and growth,” says The U.S. Department of Energy's School Operations and Maintenance: Best Practices for Controlling Energy Costs.
School maintenance staffs need to monitor windows and doors closely to make sure that they close tightly. Caulking and weatherstripping are among the ways to help minimize air infiltration and can reduce energy waste effectively.
“Choose a type of weatherstripping that will withstand the friction, weather, temperature changes, and wear and tear associated with its location,” says the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy. “For example, when applied to a door bottom or threshold, weatherstripping could drag on carpet or erode as a result of foot traffic. Weatherstripping in a window sash must accommodate the sliding of panes — up and down, sideways or out. The weatherstripping … should seal well when the door or window is closed while allowing it to open freely.”
The types of windows a school installs also can boost energy performance. Facility managers should select windows that minimize the amount of heat lost and gained. Low-emissivity coatings often are used to reduce heat loss and gain, and enhance a window's energy conservation.
The National Fenestration Rating Council has established measurements to determine the efficiency of windows. The U-factor is a measure of how much heat is lost through a window; the solar heat gain coefficient (SHGC) is a measure of how much solar radiation is transmitted through a window; and air leakage is a measure of how much air infiltration is around a window.
Protecting assets
Doors and windows should be able to endure the gradual wear from wind, rain and other weather conditions. They also should be sufficiently sturdy to withstand daily battering from students, and intentional abuse and damage often inflicted on them by vandals or would-be intruders.
That means heavy-duty doors that close properly so they can't be jimmied open. Some campuses might want to consider installing camera systems to monitor doors in troublesome areas or using access-control systems that can track who enters and exits a building.
Many school doors that lead to the outside do not have handles or locks on the exterior to prevent outsiders from entering.
Safe school guidelines put together by the Florida Center for Community Design and Research at the University of South Florida recommend that schools install doors that have hinges with non-removable pins and strike plate covers to prevent tampering; wire-glass openings to provide visibility in doors along main egress routes; and kickplates on classroom, assembly and circulation doors to prevent damage.
Kennedy, staff writer, can be reached at mkennedy@primediabusiness.com.
A security checklist
The San Diego County Office of Education has compiled a checklist to help school administrators assess the security in their buildings. Here's what it recommends to look out for with regard to windows and doors:
The main administration office should have a display of the status of alarmed doors and windows.
Storage rooms and computer labs should be situated in the building's interior, and should have no exterior windows and doors.
There should be two-way visibility in doors at building entrances, stairways and corridors.
There should be a clear view of room interiors from doorways.
Doors to areas that are not open to students should have one-way visibility (inside to outside) or peepholes.
Doors should have outside hinges with non-removable pins.
All building and room doors should have shielded locks.
Door keys should be impossible to duplicate.
Doors should have alarmed, self-locking emergency exits; exterior windows also should be alarmed.
Windows should:
Have good locks and strong frames.
Have no broken glass.
Be oriented to provide good views of outside activity areas.
Not be obstructed by signs, displays or plants.
NOTABLE
0.35 (or less)
The recommended U-factor for doors and windows in a northern climate.
0.40 (or less)
The recommended U-factor for doors and windows in a central climate.
0.75 (or less)
The recommended U-factor for doors and windows in a southern climate.
Source: Energy Star Fenestration
Guidelines, U.S. Department of Energy
Acceptable Use Policy blog comments powered by Disqus
