Skylights: A Nice Feature, With Notable Tradeoffs Here

A skylight is a legitimate flashing point, no different in principle from the chimney and vent flashing covered in our thermal cycling article — it's a place where two different building elements meet, and that seam needs to hold up through the same daily expansion and contraction stress as everywhere else on the roof. Beyond flashing, skylights bring a desert-specific consideration: heat gain. In a climate with the UV intensity covered in our altitude article, an unshaded or poorly glazed skylight can add meaningfully to cooling load, not just aesthetic value.

Glazing matters more here than in milder climates. Low-E coatings and tinted glazing options reduce both heat gain and UV transmission significantly compared to basic clear glazing, and the difference is more noticeable in a high-UV climate than it would be somewhere with less intense sun exposure.

Roof-Mounted Swamp Coolers: A Distinctly Regional Roofing Concern

This is where New Mexico differs from most of the country in a way that directly affects roofing: evaporative coolers ("swamp coolers") are common as primary summer cooling here, more so than in most U.S. climates, and rooftop-mounted units sit on curb mounts that penetrate the roof membrane directly — the same kind of penetration point as a skylight or vent, with its own maintenance profile.

Flashing around the curb mount deteriorates over time, the same thermal cycling stress covered elsewhere in this series, and it's a common leak source unrelated to the cooler's water systems entirely.

Winterization is the detail most likely to cause expensive damage. A water supply line that isn't properly drained and isolated before the first hard freeze can rupture, sending water into the roof assembly or attic space. Albuquerque's average first freeze falls in mid-November, and service demand for winterization typically surges in October — worth scheduling ahead of that window, not after the first cold snap already happened.

Why Ventilation Design Is Different for Swamp Cooler Homes

Evaporative coolers need a dedicated air pathway to function correctly — cooled air has to have somewhere to go, typically through open windows or, more commonly, through attic "up-ducts" that vent into the attic space and out through an attic vent. This means attic ventilation on a swamp-cooler home isn't just about heat and moisture management the way it is on a standard AC-only home — it's also part of how the cooling system itself is designed to work, a fundamentally different consideration than our general ventilation article covers for AC-only homes.

What This Means Practically for Homeowners

  • If you have a skylight, ask specifically about glazing type during any inspection or installation — this matters more here than the general national conversation about skylights suggests.
  • If you have a roof-mounted swamp cooler, schedule winterization before the first freeze, not after — this is the single most preventable, and most costly, failure point.
  • Flashing around any rooftop equipment deserves the same attention as chimney and vent flashing — it's a leak source people sometimes overlook because it's tied to HVAC service, not typically thought of as a roofing concern.