A growing number of designers are turning to interior glass walls and door systems to help flood interior spaces with natural light. Interior glass is a simple daylighting method, but designing these systems can be tricky, says Marc Gordon, AIA, principal architect with Spacesmith. Gordon has led the design efforts on a number of interior glass installations, including the New York headquarters for asset management firm Wilkinson O'Grady. Gordon offers the following design tips based on his experience with interior glass:
1. For complex installations, build a mock-up to ensure proper fit and clearances for glazing components and hardware. “Without mock-ups, there is a risk that the glazing and components will not fit properly and will require costly adjustments,” says Gordon.
2. Carefully evaluate the floor condition when glazing is detailed to meet the floor. If the floor is not level or is irregular, the glazing will not be able to be installed properly. Variations in the floor level should be addressed to make sure that floor channels are level and true without extensive shimming.
3. Provide adequate blocking and support to secure a structure. Blocking is typically accomplished with the use of steel or aluminum angles above the ceiling.
4. Account for the header condition, clearances, and blocking when installing overhead recessed door closers in a glazing application. Certain floor slabs, such as waffle slabs, cannot have holes cut into them to accept floor closers. When floor closers for patch or rail hardware cannot be installed, overhead recessed closers are a viable option.
5. Specify the proper glass thickness for the type of application. Avoid using thick glass where it is not required and thin glass in long-span applications, where bending or flex is a concern.
6. Be aware that “clear” glass may have an inherent green or blue tint. This may vary by manufacturer and the type of glass specified.
7. Avoid exposing the edge condition of laminated glass. When the edge is exposed, a line of the plastic interior sheet will be visible.
8. Don't try to cut or drill tempered glazing in the field. This requires special tools and must be done in the factory.
9. When specifying acid-etched or sandblasted glass, make sure the owner is up to the task of cleaning and maintaining the glass. The exposed frit of acid-etched or sandblasted glass is difficult to clean because the open-pore surface absorbs grease and oils. Cleaners should be used per manufacturers' recommendations.
10. Be aware of lead times when specifying specialty glazing. Some standard glass types are kept in stock by suppliers and are readily available. Others must be custom manufactured.
11. Don't forget to incorporate distraction markings. These stickers will deter people from walking into the glass. They should be treated as graphical elements that work in harmony with the overall design.