Nondestructive Testing of Building Envelope Systems Using

Infrared Thermography

John Snell and Rob Spring

Snell Infrared

Montpelier, Vermont

800-636-9820

www.snellinfrared.com

ABSTRACT

The structures we live and work in are susceptible to quality and performance problems during construction and

maintenance that can impact performance and may, in some cases, render them dangerous. Regardless of the

building type involved, infrared thermography also known as thermal imaging can provide remarkable,

nondestructive information about construction details and building performance.

This paper discusses the numerous applications for the technology currently being used to inspect building

envelopes. These include validation of structural details, verification of energy performance (conduction and air

leakage), location of moisture intrusion, and the identification of structural and system degradation of roofs and

facades. Examples will be given for each application and the basic conditions required will be discussed.

1.

INTRODUCTION

Buildings of all sorts, from homes to factories to high rises, can be troubled by problems related to design,

construction and maintenance that can be difficult to diagnose and resolve. The major problems found in buildings

include:

• excessive energy use due to missing or damaged insulation, insulation that is performing inadequately,

and excessive air-leakage across the thermal perimeter

• moisture damage due to leaks or condensation, especially in the walls or roofs

• ice damage to sloped roofs

• poor HVAC distribution or performance

• inadequate verification of construction details or structural performance

• delaminations of façade materials

• “sick building syndrome,” mold growth and other health related issues

Often the problems—as well as their causes and

consequences—simply cannot be seen until after costly damage

has been done. At that point the only recourse may be

extensive, costly reconstruction. The commercial building in

Image 1, a nursing home, had extensive problems resulting

from a poorly designed roof/ceiling insulation system; these

included excessive heat loss during the winter months and, as a

result, extensive ice damage due to snow melt. Hundreds of

thousand so dollars were spend in various, poorly planned

attempts to correct the underlying causes. In the end the owners

simply lived with the continued problem because corrective

actions were deemed too expensive. Despite this unfortunate

resolution, the thermograms helped the owners negotiate a

financial settlement with the architects and contractors.

Image 1. Excessive heat loss and poor

ventilation resulted in costly ice damage to

this large roof.