AtticInsulationCalculator.com
Rigid Board

XPS Foam Board Insulation

Complete guide to xps foam board insulation: R-value, installed cost, pros, cons, and best applications.

Key Specifications

4.7–5
R-Value per Inch
$0.70–$1.30
Material Cost/sqft
$1.40–$2.30
Installed Cost/sqft
13"
Depth for R-60

Cost Analysis (1,200 sq ft Attic)

OptionLow EstimateHigh Estimate
Material only (DIY)$840$1,560
Professionally installed$1,680$2,760

*Estimates for a full install to Climate Zone 5 R-60 depth. Use the calculator for your specific situation.

+ Pros

  • Higher R-value per inch than EPS (4.7–5.0)
  • Excellent moisture resistance
  • Consistent performance across temperature ranges
  • Strong compressive strength

Cons

  • Higher global warming potential than EPS
  • R-value drifts slightly over decades as blowing agent escapes
  • More expensive than EPS
  • Must be covered with thermal barrier

Best Applications

  • Continuous insulation on roof deck (above-deck)
  • Situations requiring thin profile with high R-value
  • Below-grade applications with high moisture exposure

Comparing Insulation Types

XPS Foam Board is a rigid board insulation. With R-4.7–5 per inch, it delivers solid performance for most climate zones.

View full insulation type comparison →

Is XPS Foam Board Right for Your Attic?

Use our free calculator to get a personalized recommendation based on your climate zone, attic size, and budget.

Calculate My Insulation Needs