ASHRAE Publishes New Guideline on Energy Efficiency for Historic Buildings

ASHRAE published a new guideline for increasing energy efficiency in historic buildings while minimizing the disturbance of the building’s historic character and significantly historic characteristics and materials.

ASHRAE Guideline 34-2019, Energy Guideline for Historic Buildings, provides comprehensive and detailed descriptions of the processes and procedures for the retrofitting of historic buildings to achieve greater measured efficiency. The guideline is particularly aimed at providing guidance for “listed” historic buildings; i.e., those formally designated or eligible to be designated as historically significant by a governing body.

Guideline 34 provides a step-by-step procedure for sensitive energy upgrading, beginning with forming the project team and gathering building and energy use histories, to instituting energy-efficiency measures. Building envelope improvements, environmental control strategies, energy system analysis, HVAC selection and lighting design considerations are all addressed in the guideline. All recommendations are made in consideration of preserving the integrity of the historically valuable building character, materials and associated artifacts.

Many historic buildings were constructed without insulation and designed without active air conditioning systems—especially for mechanical cooling. Retrofitting such buildings requires specialized techniques during construction and operation, as well as sensitivity to respecting and preserving historical significance.

With nearly two-thirds of existing buildings estimated to still be in service by 2050, project teams retrofitting any historic building for energy efficiency can benefit from the content of the guideline.

The cost of ASHRAE Guideline 34-2019, Energy Guideline for Historic Buildings is $53 for ASHRAE members ($62, non-members). To order, visit or contact 1-800-527-4723 (U.S. and Canada), 404-636-8400 (worldwide) or fax 678-539-2129.