Carolina Municipio, PR Insulation Payback
Attic insulation payback for Carolina Municipio, PR
DOE classifies Carolina Municipio as climate zone 1, hot-humid — summers that stay hot and humid while winters barely register on the energy bill. Its recommended attic R-value for bare joists is R-30. For an attic around 1,000 square feet, closing the gap from R-2 to R-30 costs around $1,680 and saves an estimated $843 a year — payback in roughly 2 years. Hard to find a home improvement with a faster payback than this.
Heating vs. cooling in Carolina Municipio
Of that, about $0/year comes from reduced heating and $843/year from reduced cooling load through the ceiling. Carolina Municipio beats 6% of the counties in this 3,162-county dataset on estimated insulation savings. Among the 81 counties DOE places in zone 1, Carolina Municipio ranks 14th. Against Puerto Rico's own average of $660/year, Carolina Municipio runs 28% above that.
Where these numbers come from
NOAA's WFO SAN JUAN, PR RQ station, 2.8 miles from Carolina Municipio, supplies the 0 HDD and 5,433 CDD this estimate runs on. By total degree days, Carolina Municipio sits at the 38th percentile nationally. DOE also classifies Carolina Municipio as moisture regime A (humid) - ask a local contractor whether that changes the vapor-barrier approach for this job.
The smaller top-up scenario
If Carolina Municipio's attic already has 3-4 inches of old insulation (about R-11) rather than bare joists, the recommended target drops to R-25. That smaller top-up costs around $840 and saves an estimated $92/year — payback about 9.1 years. It is close - the payback only just fits a reasonable timeframe.
Next steps for a Carolina Municipio attic
Get more than one quote before committing. Attic access and any needed air sealing move the price around, and most contractors won't take a job below roughly $600 regardless of size - worth asking upfront given Carolina Municipio's estimated $843/year on the line.
More on how this was built
Nothing here is a guess: the methodology guide names the DOE climate map and NOAA station data behind every number on this page. See the DIY vs. contractor guide for whether a job this size is realistic to do yourself.