SnowLoadCheck

Jefferson County, KY Roof Snow Load - 15 psf

What ASCE 7 says about snow load in Jefferson County

Moderate
15 psf

That's Jefferson County's design roof snow load per ASCE 7-22, for a typical heated single-family home - the number a permit reviewer starts from. §7.3.4's low-slope minimum of 15 psf is what actually governs on a flat or low-pitch roof here - higher than the 10.5 psf the base ground-load formula gives.

Converted to something you can actually eyeball on a roof: about 33 in. of fresh powder, 12 in. once it settles and packs down, or just 3 in. if it's turned to ice. A meaningful design load. Most homes built to modern code handle it, but additions, carports, and flat-roofed sections are worth a second look.

Jefferson County in numbers

Where Jefferson County's figure sits nationally

Out of 2,758 rated US counties, Jefferson County sits at #1,309, the top 47% nationally - #17 of 120 within Kentucky. Kentucky counties average 15.7 psf; Jefferson County runs 0.7 psf lower than that.

Near 38.1895°N 85.6576°W, FIPS 21111: Jefferson County counts 793,881 residents and a 15 psf map value, which the code's own factors turn into 15 psf.

How much it actually snows in Jefferson County

Most winters bring Jefferson County roughly 13.4 in. of snow - NOAA's normal at LOUISVILLE INTL AP, KY US, 4.5 mi off. (fresh vs. packed vs. ice explains why.)

Read this before you rely on it

Jefferson County's number above is ASCE 7-22's default case, not a custom calculation: ordinary residential occupancy, heated, sited on ground that's neither fully sheltered nor fully exposed. Any one of those changing - pitch, exposure, heating, occupancy - moves the real figure.

Nothing here substitutes for an address-level number. Get one free, in about a minute, from the ASCE 7 Hazard Tool using your own coordinates rather than Jefferson County's county-wide figure. See the methodology guide.