Comparison between polystyrene and fiberglass roof insulation in warm and cold climates

Khaled A. Al-Sallal

Research output: Contribution to journalArticlepeer-review

66 Citations (Scopus)


This study clarifies the law of diminishing returns when improving the conservation level of residential buildings by using case studies simulation. It explores the effect of different climates on the decision of selecting the insulation type and thickness. It shows the importance of using the life-cycle cost model on the decision of adding more insulation levels and knowing when to stop. RENCON program was employed to estimate the annual heating and cooling requirements of a 108 m2 house. The analysis was carried out for several cases of two types of roof insulation (polystyrene and fiberglass) in two different locations (College Station, Texas and Minneapolis, Minnesota.) R5 was found to be the most cost effective thermal resistance in polystyrene in both locations. In fiberglass, R10 was the most cost effective. It was found that investing money to improve the insulation levels in the cold climate house has better returns than that of the warm climate.

Original languageEnglish
Pages (from-to)603-611
Number of pages9
JournalRenewable energy
Issue number4
Publication statusPublished - Apr 2003


  • Energy conservation
  • Law of diminishing returns
  • Life-cycle cost
  • Payback time
  • Thermal resistance

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment


Dive into the research topics of 'Comparison between polystyrene and fiberglass roof insulation in warm and cold climates'. Together they form a unique fingerprint.

Cite this