Skylight Replacement During a Reston Re-Roof

Why decide during the re-roof

A skylight is a hole in the roof sealed by flashing and the unit's own seals. On a re-roof, the old flashing around it is normally removed with the shingles. If the skylight stays, it has to be re-flashed into the new roof. If the unit is old, replacing it now means its flashing is integrated with the new roof once, instead of the roof being opened up again later around a failing skylight. Removing a skylight is also easiest when the roof is already off.

Signs a skylight should be replaced, not just re-flashed

• Fogging or condensation between glass panes, which suggests a failed seal.
• Cracked, crazed or yellowed glazing.
• Rot, stains or soft spots on the curb or the interior drywall around the opening.
• Leaks that continue after previous flashing repairs.
• A unit old enough that matching flashing kits and parts are hard to find.

A skylight that's in good condition can often stay, as long as it's re-flashed properly. Ask what flashing will be used and whether the curb height still suits the new roof.

Removing skylights

Some owners find old skylights leak, overheat rooms in summer, or simply aren't worth keeping. Removal means framing in the opening, decking over it, roofing across it, and repairing the ceiling inside. It's a real change to the roof and the interior, so it should be its own line in the scope.

It's also something Reston Association has approved as part of a re-roof. February 2024 DRB minutes record an approved replacement roof on a detached home in GAF Timberline HDZ algae-resistant architectural shingles, color Charcoal, that included removing six skylights.

Skylights and your approval

Skylights are part of the roof's appearance, so they belong in your Reston Association application or advisor conversation, whether you're keeping, replacing, adding or removing them. Some cluster standards address skylights directly. Waterview Cluster's handbook, for example, lists skylights among modifications that need RA design review approval. Reston Town Center's residential design guidelines have their own skylight section. And RA's cluster teardown and infill guideline says skylights and similar elements not shown in previously approved plans must be reviewed before installation.

• Keeping existing skylights: say so in the application and show them in the elevation photos.
• Replacing like-for-like: note the unit and flashing color; ask whether your standard specifies a profile or frame color.
• Removing: list the number and locations removed, as the 2024 example did.
• Adding: expect review; adding openings is a design change, and some standards have specific rules.

Flashing basics

Most skylight leaks aren't the glass. They're at the flashing: the step pieces along the sides, the head flashing at the top where water arrives, and the apron at the bottom where it leaves. Debris piling up on the uphill side, a common problem under Reston's trees, slows water down right where the flashing is most vulnerable. A clean flashing installation that suits the skylight model, plus a clear path for water around the curb, is the goal.

Skylight work in progress and finished skylights with new ridge caps on a Roofing Roughnecks roof in McLean.

Skylights under trees

Many Reston roofs sit under mature trees, and that changes the skylight conversation. Leaves and needles collect against the uphill side of the curb, hold water there, and stain or rot the curb over time. When you replace a skylight under heavy canopy, ask about the flashing kit and curb design, and plan to clear the uphill side each fall. If the skylight mainly lets in shade and debris, removal may be the better choice.

Planning it into the scope

Your written scope should say, skylight by skylight, what happens: re-flash, replace, or remove and deck over, plus any interior ceiling repair. Skylight work is one of the cost drivers that moves a roof within the division's typical Northern Virginia reference ranges, so it's worth having the decision made before you compare estimates.