E-Book, Chapter 3: The Impact of Structure on the Renovation Cycle

Many people tie the longevity of a building to the structural system. Is this correct? Studies show that disposition of buildings is mostly tied to space utilization reasons and is rarely tied specifically to performance of structural systems.

This article is part of a 10 part series, E-book, on The Coming Renovation Cycle. Over 50% of our schools and commercial buildings are now 50 years old or older. These facilities are heading headlong into their renovation cycle. This week, we explore the impact of structural systems on The Renovation Cycle.

There are many factors that must be considered when considering the renovation of a building. Although we might intuitively think that structural systems are a primary driver in the renovation decision, research tells us that structural systems are less of a consideration than you might think,

Structural systems typically last longer than other systems and generally have a 75 to 80 year expected useful life. However, many people try to tie the longevity of a building to the structural system. Studies show that there is actually little correlation between the structural system and life of a building. In many ways, wood-frame systems may be easier to modify than steel or concrete. When it comes time to complete a gut rehab, modifying spaces or adding spaces is often easier in a wood or steel frame system than a concrete frame system

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The following information is an excerpt from? A Survey on Actual Service Lives for North American Buildings was presented by Jennifer O’Connor, Research Scientist Forintek Canada Corp., Vancouver, B.C., Canada. The paper was presented at Wood-Frame Housing Durability and Disaster Issues Conference in Las Vegas, NV in Oct. 2024

Studies show that disposition of buildings is mostly tied to space utilization reasons and is rarely tied specifically to performance of structural systems. Building operational systems and level of historic maintenance are key contributors to decisions to dispose of a facility rather than renovate.? Facility Condition Assessments are well known for producing FCI indexes that track the cost of replacing systems with capital investment with the cost of full replacement in today’s dollars. From a purely mathematical calculation this is the best starting point in the discussion of whether it is still cost effective to invest in the existing building or not. I point you to research completed in 2004 by a Canadian research team who studied the reasons that buildings of all uses and construction types ended up in the trash-heap of history.

“Some buildings lasted just a few decades while others lasted generations. The structural systems had little to do with which buildings met or exceeded their EUL. Survey on actual service lives for North American buildings, 2004.?

This paper presents results of a demolition survey in a major North American city that captured building age, building type, structural material and reason for demolition for 227 buildings. The findings challenge many common assumptions about building longevity, and, in particular, the relationship between structural material and service life. Although it is often believed that “durable” structural materials such as steel and concrete will provide the longest service lives for their buildings, our results suggest there is no significant relationship between the structural system and the actual useful life of the building. Reasons for demolition were instead related to changing land values, lack of suitability of the building for current needs, and lack of maintenance of various non-structural components. Only eight buildings identified a specific structural failure. Indeed, the service lives of most buildings are probably far shorter than their theoretical maximum lives; the majority of demolished steel and concrete buildings in our study were less than 50 years old. In the context of sustainable construction, this raises some interesting questions and shifts the spotlight away from durability of materials and on to the following:

1)???? flexibility of design to allow future changes;

2)???? deconstructability; and

3)???? the use of more accurate life span predictions in life cycle assessment calculations on whole buildings.

An insightful article on adaptive reuse can be found at https://www.buildings.com/industry-news/article/10192861/adapting-an-older-building-for-a-new-use Here is an excerpt from this article:

?Decision to Tear Down Walls

"The first step in renovating an older building is taking everything down to the studs. Once the drywall or other materials are off the walls, the engineers can more easily see which ones have ducts and where electricity and plumbing currently is. It’s easier to come up with a plan for the future layout if everything is located, because not every element will need to be replaced.

Verifying Structural Integrity

Walls should not be removed without seeking the advice of a structural engineer who specializes in commercial buildings. Nobody wants to invest thousands into remodeling only to have the ceiling fall due to instability. This is also a good time to get the foundation of the building inspected and ensure any floors?above the ground floor are sound. Furthermore, consider the operational and changing structural needs of the school or other facility — areas that might hold heavier loads, such as a library, should be reinforced.”

Facility Condition Assessments are the first step to preparing for and prioritizing your asset management goals. Having consistent and defensible data will help you to plan for and budget for the coming landslide of renovation.? This E-Book attempts to identify and explain the issues related to the coming renovation cycle. In the next chapter, we will look at “Hitting the Sweet Spot for Renovation, Restoration, and Adaptive Reuse.

In Chapter 2 of this E-Book, a variety of decisions were identified that inform decisions related to restoration, renovation, and adaptive reuse. Structural considerations, outlined here in Chapter 3 are certainly important, but there are many other influences on decisions to altering and extending the life of an existing building. In Chapter 4 of this E-book, we will explore the importance of infrastructure on decisions to renovate, repurpose, or demolish.