Skylights near you

NFRC publishes what each number on the label means, and the directions are not all the same. U-factor measures how well a product keeps heat from escaping a room, and lower is better. Solar heat gain coefficient measures how much solar heat a product lets in, so low numbers resist solar heat and high numbers admit it. Visible transmittance measures how well the product lights the room with daylight, and higher means more natural light. Air leakage measures how much air will enter a room through the product. Condensation resistance is reported as well, which matters more on a skylight than on almost any other opening.

ENERGY STAR then sets thresholds by climate zone, and its criteria for windows and skylights are based on the NFRC-certified ratings rather than on a manufacturer's own testing. Because the criteria vary between zones, the first step is finding which zone you are in, and the second is asking the installer for the NFRC label numbers for the exact model being quoted, not for the product family.

Orientation and room use complicate it in a way worth thinking through. A skylight faces upward, so it sees sun that a wall window never does, and a unit chosen for daylight in a stairwell is being asked to do a different job from one over a south-facing kitchen in a hot climate. The label lets you weigh daylight against heat gain deliberately instead of guessing.

Nearly every skylight leak is a flashing story. The unit comes with a flashing kit designed for a particular covering and a particular slope, and it has to be integrated with the underlayment and the shingles or panels around it so every upper layer laps over the one below. Substituting sealant for that lapping is the single most common defect, and it works for a season or two before it does not.

Everything above the skylight matters as much as the unit. On a sloped roof the skylight interrupts the path of water coming down the slope, so what happens at the head of the unit, and how any valley or roof plane above it is directed, decides whether water is spread around the frame or funneled at it. On a low-slope roof the same logic argues for a proper curb so the frame sits above standing water rather than in it.

Then there is the inside. A new skylight usually means framing an opening, cutting and headering rafters, and building a shaft through the attic, which has to be insulated and air-sealed as carefully as the ceiling it interrupts. A shaft that leaks warm indoor air into the attic will produce condensation and ice problems that look exactly like a roof defect. If the work involves cutting a new opening or altering rafters, that is a structural change and belongs on a permit.

Federal workplace rules name skylights explicitly, and the language is blunt. Under the construction fall protection standard, each employee on a walking or working surface must be protected from falling through holes, including skylights, more than six feet above lower levels by personal fall arrest systems, covers or guardrail systems, must be protected from tripping into or stepping into or through holes, including skylights, by covers, and must be protected from objects falling through holes, including skylights, by covers. The general industry standard sets the same idea at a lower threshold, requiring protection from falling through any hole, including skylights, four feet or more above a lower level.

The requirements for those covers are just as specific: a cover over a hole in a roof must be capable of supporting, without failure, at least twice the weight of the employees, equipment and materials that may be on it at any one time, must be secured when installed so wind, equipment or workers cannot displace it, and must be colour coded or marked with the word HOLE or the word COVER to warn of the hazard. A homeowner cannot be expected to build one of those, but knowing the rule explains why a competent crew does not simply step around a skylight, and why nobody should lean on, sit on or walk near one while work is going on.

Safety glazing is where expectations often run ahead of the rules. The Consumer Product Safety Commission's architectural glazing standard applies to a closed list of architectural products, and everything on that list is a door, a door-type enclosure or a glazed panel. Skylights are not among them. What your skylight glazing has to be is therefore a question for the building code your state and city have adopted rather than for the federal standard. Ask the building department what the adopted code requires given where the unit sits and how far it is above the floor, and ask the supplier what the model is actually glazed with.

Cutting a new skylight opening means altering roof framing, which is the kind of work building departments want to see. A like-for-like replacement in an existing opening may be treated differently, and the line moves from city to city, so ask the building department the specific question with your address before you order a unit.

The licensing answer often surprises people, because skylight work can sit in more than one trade. In Arizona, the roofing classification covers the weatherproofing and roof accessories needed to install and repair coverings, while the sheet metal classification, R-45 for residential and C-45 for commercial, separately lists skylights alongside flashings, gutters, leaders and metal roofing systems. Either licensee may be the right company, and on a job that also involves framing and interior finishing you may be dealing with more than one.

Elsewhere, check the structure your own state uses. Washington registers contractors and publishes a verification tool for confirming that a registration is active, that the contractor is bonded and insured, that any job site violations were corrected and what the license history shows, and it advises homeowners to collect at least three written bids and to sign a written contract they actually understand. LokalMatch is the step before all of that: describe the skylight work once, including whether it is a new opening or a replacement, the roof covering, the ceiling height and any staining you have already found, and installers serving your area contact you directly. Those pros pay for the requests they receive. LokalMatch does not install skylights, does not set prices, and does not vet, rank or recommend anyone, so the licence check, the NFRC numbers and the flashing plan are yours to compare.