This paper presents simulated performance ofinsulation/radiant barrier systems under differentTexas climates. A transient heat and mass transfermodel which predicts thermal performance ofresidential attics (Medina, 1992) was coupledwith an "economic" subroutine. Simple paybackperiods were estimated which were based on currentinsulation and radiant barrier (RB) prices (materialsand installation), and current and forecast electricrates. It was found that when the analyses werebased solely on reductions of ceiling heat loadsduring the summer time, a combination of R-11 withRB was more effective than upgrading the insulationlevel to R-19. Similarly, adding a radiant barrier toan existing insulation level of R-19 proved moreeffective than upgrading to R-30. When heat gainsto the cold air traveling inside A/C ducts (which areusually installed in attic spaces) were considered, allinsulation/radiant barrier combinations showedfaster payback periods than insulation upgrades,During the winter time, insulation upgrades provedto be more effective than insulation/radiant barriercombinations. The simple payback analysespresented herein include both summer and wintersimulations.
展开▼
