Adaptive reuse, the practice of renovating an existing building for a purpose other than that for which is was built, is a popular practice and seen by many as a key factor in land conservation and the reduction of urban sprawl. While these are often fun, creative projects, they can also provide certain challenges for engineers. After all, you never know what’s lurking behind those walls! In this post, we’ll look at the information an engineer needs for a renovation project, common challenges in obtaining that information, and tips for mitigating those issues.
What You’re Looking for in a Renovation A renovation project can be anything from cutting openings in walls or floors to creating a new layout to as much as moving walls and columns or removing entire floor systems. To know what can be done in an existing space, it’s essential to know the existing conditions. Initial review should include looking for things like existing framing systems, load bearing walls, lateral force resisting systems (such as braced frames), expansion joints, and floor or deck composition. For most projects, this information can be obtained from a combination of existing building documents and an on-site review.
Potential Issues in the Assessment Phase The first step is always to obtain the existing building documents. If available, they can provide the information on the existing building system and eliminate the need to be on site. However, these documents may not always be complete or include the information needed for the proposed renovation. Sometimes documents are from previous renovations, but not the documents for the original buildings. Or documents could be from the 1900s and have deteriorated, making them hard to read. Finally, documents could be from a different discipline, such as the architectural plans instead of the engineering plans.
When the documents don’t provide all the necessary information, an on-site review to visually assess the building is necessary. This involves going into crawl spaces, popping up ceiling tiles, etc. There are several issues that can arise at this stage, the biggest of which is access. If the building has hard ceilings (as opposed to tiles) or dry wall, selective demolition is necessary to access behind those materials. This can be a challenge if the building is currently occupied. No one wants someone standing on their desk to cut a hole in the ceiling above. Another access example would be working on a site that is far away. This could involve a local representative sending pictures, hoping they get the best perspective needed to make critical assessments.
Tips for Mitigating Issues In terms of obtaining the right documents, it’s best to go through as many options as possible and ask multiple people at the same source. Someone may say they don’t have any documents or can’t send them, but another person in the same agency may have the information. Don’t give up at first denial. Exhaust all options since existing documents will be the most helpful part of the design work.
When a building is occupied, but it’s necessary to see what’s behind the walls, choose an area for selective demolition that is out of the way. The goal is to minimize the impact to occupied spaces, so try to find alternative locations like mechanical rooms, stairwells and bathrooms.
All of this detective work makes a big impact in designing for the adaptive reuse. Knowing as much as possible about the existing conditions helps reduce surprises during construction. For example, a client wants to turn an existing office space into a daycare center, but there are no existing documents. Even though much can be learned during the onsite review, once a contractor starts removing sheetrock and floor finishes, it may be revealed that certain areas are not as was assumed in the assessment phase. This results in design modifications during the construction process. Sometimes that’s simply unavoidable and just part of an adaptive reuse project. However, the more these issues can be overcome in the assessment phase, the fewer modifications will be necessary down the road. While it can be fun to find hidden surprises in a renovation project, surprises in the construction phase don’t hold nearly the same charm.
About Janice Weaver, SE, PE
Janice Weaver leads Foresite Group’s Structural Engineering Division nationwide. As a structural engineer, Janice has always loved the relationship between the bones of a building and how they can be used to support an architectural vision. She has a Bachelor’s and Master’s degree in Civil Engineering from the Georgia Institute of Technology and has been with Foresite Group since 2014. She has more than 10 years of experience providing structural design services for a wide array of clients and industries.