VITRO / PLANNING GUIDE
Choosing Glazing for Heat, Sound and Safety
Glass influences the daylight, appearance and comfort of a room. A useful specification begins with clear priorities: controlling solar heat, reducing unwanted noise, addressing safety requirements and preserving the view. Several glass technologies can be combined, but each has a different purpose.
Understand the performance numbers
When comparing proposals, ask for the relevant technical data and check whether it describes the glass alone or the complete window or door. Compare figures on the same basis.
Solar heat gain coefficient (SHGC): describes how much solar heat is admitted. A lower value means less solar heat passes through the product.
U-value or U-factor: describes heat transfer caused by a temperature difference. A lower value indicates better insulation.
Visible light transmission: describes how much visible light passes through. Review it alongside solar control and the desired appearance.
These distinctions are explained in the U.S. Department of Energy's window performance guidance. The appropriate specification still depends on your building and location.
Separate insulation from solar control
Insulated glazing uses panes separated by a sealed cavity. Low-emissivity, or low-E, coatings influence heat transfer, while the coating selected also affects solar gain. Low-E products have different solar-control characteristics; the name alone does not establish the performance you will receive.
Consider orientation, overhangs and air-conditioning use when reviewing the options. Ask to see a sample when glass color, reflectivity or the view through adjacent panes is important to the design.
Specify sound control deliberately
Laminated glass incorporates an interlayer between glass panes. Special acoustic interlayers can improve sound insulation. Share the source of the noise and the rooms that need attention, then request appropriate acoustic data for the proposed assembly. Frame construction, seals and installation also need consideration.
Review how the glass behaves if broken
Tempered and laminated safety glass behave differently. Tempered glass breaks into small pieces; laminated glass typically retains fragments on its interlayer. Selection should address the specific application, including doors, low-level glazing and any risk of falling through an opening. Confirm the required glass construction with the project designer.
Bring the glass and frame together
A thermal break concerns the frame: a less-conductive material separates aluminum components to reduce heat flow. Review the glass, frame and installation details as one specification.
Explore our aluminum windows, sliding doors and completed projects. Send VITRO your plans and priorities to discuss the options for your project.