Design Guide for Parapets: Safety, Continuity, and the Building Code

Parapets serve not only as a functional building component, but also as an aesthetic statement. By incorporating elements such as cornices, bands, pediments, balusters, and embattlements, a parapet can provide a continuation of the facade, or a visual termination.

Fundamentally, the parapet serves many practical purposes beyond its original function of protecting inhabitants from invasion. The modern parapet must provide fire protection, serve as a fall-protective guard, transition and protect the roof/facade interface, conceal rooftop equipment, and contribute to the aesthetic character of the building.

As knowledge about building science has evolved, building codes have been developed to disseminate standards for the safe and functional design of parapet walls, and design professionals must consider these regulations when designing or rehabilitating parapets.

LEARNING OBJECTIVES:

• Describe the design of parapet components, including copings, cladding, sealants, mortar joints, in-wall flashings, and vapor barriers, and explain how each functions to protect wall and roof assemblies from water infiltration.
• Discuss the impact of code requirements for energy performance (e.g., the International Energy Conservation Code) on parapet design, including regulations for continuous insulation and air and vapor barriers.
• Evaluate structural considerations for new and existing parapets, addressing wind loads, height requirements, and accommodation for movement as part of a comprehensive design that provides the requisite safety and stability.
• Apply best practices for assessing existing parapets to determine appropriate repair and/or replacement strategies that meet code requirements, comply with historic/landmark preservation regulations, and respect the aesthetic integrity of the building.