When does building design really begin? Does it start when the architect meets with the project owner for the first time? How about when the first schematic sketches are drawn? When an AutoCAD file is created? An argument can be made for each of these steps being the starting point of building design, but the decisions with the greatest impact on a project are made far earlier than many would suspect.
Consider when the structural system and wall design of a building get selected. It can be argued that it is often directly dictated by the architectural form, design details and owner requirements. Unfortunately, the wall design is usually chosen extremely early without thought for how this decision impacts the overall performance and capabilities of the project. Regardless of when the design starts, the architectural and engineering decisions made early in a project largely determine the design and material choices that will be made weeks and months down the road.
When wall systems are chosen, the rest of the design and the performance potential of a building is set in place. When a designer chooses to design a building using wood, they are committed to designing against wood rot, mold, and termite problems. If the designer chooses metal framing, they have to design against rust, thermal bridging, and structural steel connections limiting design flexibility. Most importantly, once a light-framed wall is chosen, all other options that would improve the overall performance of the building are no longer available. From that point on, the design team is playing defense, fighting all the issues that could damage or deteriorate the structure as well as limit their design ability.
It’s difficult, if not impossible, to go backwards once walls are chosen. Once a design has started and man-hours have been committed to a project, the ability to change the wall system becomes improbable. There are cost implications. No architectural or engineering firm wants to pay its employees to redo work they have already completed. There are scheduling implications. When schedules are measured by days and hours, no one wants to delay the project by redesigning the wall system. There are design implications. Once the walls have been decided, window details and depths have been set, finish system options have been narrowed, and opening spans and building heights have been defined. When all of these other design details have been decided upon or limited by the type of structural wall system chosen, dollars and complexities dictate that no other wall system can be chosen.
If you are set on constructing a better building, innovative materials must be taken into consideration at the very beginning of the design process. Otherwise, a superior building quickly becomes further out of reach.
With recent hurricanes, floods, and fires, the design community and building owners have become more focused on the resiliency of buildings. When light-framed buildings are designed and constructed, there is no way to make them more resilient. In fact, light-framed buildings only get weaker over time. A light-framed building will be its strongest and most durable on the day it is built. The structural components rot and rust, connections loosen and weaken, and the overall resiliency of the building declines as time increases. A more robust, resilient wall system must be considered at the beginning of any project to ensure a long lasting and safe building.
No global politics or government policies will keep energy prices from increasing over time. Will the owners and tenants of buildings being designed and built today be able afford the energy costs of the future? When designing buildings today, the long term operating costs must be considered, and not just at today’s energy prices. The insulating systems of light framed walls are simply not robust and generally prone to degradation. Cavity wall insulation will not perform the same as it does in lab testing once exposed to typical building life cycles. For one, any cavity wall insulation is designated with an R‑value that is lab tested and does not reflect real word conditions where stud framing interrupts the insulation, creating thermal bridging. Plus, it is difficult to fully insulate cavity spaces without compressing insulation or creating un-insulated voids. In addition, cavity wall insulation is susceptible to sagging over time and extreme performance degradation with any moisture damage. In order to design an efficient building that will perform the same throughout its lifetime, designers must evaluate the wall assembly before proceeding any further with their design.
Indoor Environmental Quality
Indoor environmental quality (IEQ) has risen to the forefront of many designers’ and owners’ project requirements. Study after study has found that worker productivity, occupants comfort, and even learning environments all experience improvement when the indoor environment is well-designed and high performing. Whether it be thermal comfort, air quality or sound attenuation, the light framed buildings we continue to build have trouble achieving the IEQ goals many owners demand. Thermal bridging and inconsistent insulation in framed buildings lead to uncomfortable temperature fluctuations, thermal hot, and cold zones in buildings. These buildings also tend to have moisture problems that lead to mold, mildew, and other air pollutants bombarding the structure’s occupants. Without building complicated multi-layered wall assemblies, light framing struggles to keep outside noise pollution from leaking into the building. Building designers must look to mitigate these issues and design for IEQ at the beginning of the project as they are selecting wall systems.
How to start with better walls.
Integrated Project Delivery (IPD) is the first step in designing better buildings with better walls. When the entire project team and owner decide on the goals of the project before any design starts, the walls of the building can be evaluated and chosen based on the goals. This eliminates having to change the building in the middle of the design to try to meet an unforeseen need.
Reaching out to manufacturers for consultative design recommendations is a great first step in getting started on a project design. Manufacturers have the testing data, past project history, and design parameters at their fingertips to assist the designer early in a project. Take advantage of their consultative approach to determine the best wall system for the project.
Setting building performance metrics prior to design will help define the wall assembly needed to meet the goals. Whether it’s air change per hour (ACH), monthly utility costs, sound transmission class rating (STC), safety criteria (fire or windstorm rating) or any other metric, it should be defined prior to design. Many times the goals will direct the team to the type of wall system needed.
The Bautex Wall System should be considered early on by designers and owners. Unlike light framed walls, the Bautex wall is a resilient, continuously insulated mass wall system. It’s created with the Bautex Block and provides buildings robust, rot, rust, and mold proof walls. Headquartered and manufactured in central Texas, Bautex should be your first consideration when beginning the design of 1 – 3 story buildings. For more information, visit bautexsystems.com.