Is spray foam worth the premium over fiberglass for an old (pre-1980) home?
Verdict: DEPENDS — Worth it for vaulted ceilings, rim joists, and tight retrofits. Open attics are fine with cellulose at 1/3 the cost. Older homes have hidden conditions. Add 15–25% contingency and prioritize safety/code upgrades first.
Cost & payback at a glance
| Typical cost range | $3,000–$8,000 |
|---|---|
| Estimated annual benefit | $220/yr |
| Simple payback | ~25 years |
| System | insulation |
| Scenario | old-house |
How HomeScore decides
HomeScore evaluates "is it worth it?" decisions across 40+ home systems using 2026 cost data, regional installer rates, lifespan modeling, and resale ROI. Every verdict on this page is anchored to the underlying replacement cost, annual operating savings, and the scenario you're in: general homeowner, in-2026 pricing, resale-driven, forever-home, or pre-1980 retrofit.