Understanding Embodied Energy and Its Impact

In an era of con­sci­en­tious green con­struc­tion, archi­tects, owners and con­trac­tors have been taking a closer look at both oper­a­tional and embodied energy. A com­par­i­son of the embodied energy costs of various common building materials reveals some stunning vari­a­tions. For example, the embodied energy of plastics like polyvinyl chloride (PVC) is more than 10 times that of cement and various concrete building products.

Just What Is Embodied Energy?

Embodied energy refers to all the upfront energy use of a given material, including:

  • Mining, logging and other natural resource acquisition
  • Elec­tric­i­ty and fuel con­sump­tion during manufacturing
  • Trans­porta­tion expenses, including product delivery

It does not, however, factor in the operating costs of the building the materials are used in or the eventual disposal of the building materials used in creating the structure. Embodied energy, then, is only one component of the total life cycle energy costs of a building.

Life Cycle Assessment

ISO 14040:2006 is an inter­na­tion­al standard that addresses envi­ron­men­tal man­age­ment and sets appro­pri­ate life cycle assess­ment (LCA) protocols. A com­pre­hen­sive life cycle assess­ment looks at the full envi­ron­men­tal impact of either indi­vid­ual building materials or entire struc­tures, factoring in:

  • Raw materials acquisition
  • Refining and fabrication
  • Trans­porta­tion
  • Con­struc­tion
  • Recycling and disposal

LCA looks at a wide range of envi­ron­men­tal impacts like resource depletion, energy and water use, carbon emissions and waste generation

Failures Drive Embodied Energy Costs Higher

Per­for­mance has an impact on total life cycle costs; therefore, it is important to consider the losses and premature repairs that are asso­ci­at­ed with certain wall designs. Over the course of many projects, some of them will consume more embodied energy because of:

  • Repairs due to wall system failures (mold, mildew, rotting and corrosion)
  • Premature replace­ment due to natural disasters like hur­ri­canes and tornadoes 
  • Fire losses

Embodied Energy vs. Operational Energy

Embodied energy is an increas­ing­ly important con­sid­er­a­tion because it is often equiv­a­lent to many years of oper­a­tional energy. For example, one gov­ern­ment agency cal­cu­lates that the embodied energy in a typical home may equal as much as 15 years’ worth of oper­a­tional energy. Even though it consists only of energy used to create and deliver the building materials, the embodied energy expended for a home that lasts a hundred years can account for as much as one-eighth of its overall energy use.

The Bautex™ Wall System only uses about half the concrete required in tra­di­tion­al ICF or concrete walls and it elim­i­nates the need to apply an added layer of rigid foam sheathing. The embodied carbon in polyurethane rigid foam is 3.48 kgCO2/​kg — more than four times the embodied carbon in cement (0.73).

Unsur­pris­ing­ly, the embodied energy costs of a wall system that uses sig­nif­i­cant­ly fewer materials, like rigid foam sheathing, tend to be lower.

25 Percent Savings

Also, the more energy efficient the building is, the longer it will take for operating energy expenses to exceed the embodied energy costs. The Bautex Block Wall System reduces heating and cooling costs by 25 percent or more when compared to tra­di­tion­al wall systems. This is achieved by:

  • Con­tin­u­ous insu­la­tion (and elim­i­na­tion of thermal bridging), which provides R‑values that are 200 to 250 percent higher than those required in Texas by the 2015 IECC Energy Code.
  • The efficient use of concrete in exterior wall systems, which increases thermal mass and optimizes external heat loads.
  • Airtight building envelopes that are subject to fewer instal­la­tion errors, reducing external heat loads.

The Bautex Wall System has low embodied energy when compared to many tra­di­tion­al wall systems. The four-hour fire rated blocks are fab­ri­cat­ed using a patent-pending automated process at our plant in San Marcos, Texas. The peace of mind and other intan­gi­ble benefits of the system merit con­sid­er­a­tion as well.

We’d welcome the oppor­tu­ni­ty to discuss what the Bautex Block can con­tribute to the success of your next project. For friendly, expert assis­tance, please contact us today!