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!