fixing a leaking skylight window

I would put caulking around the outside of the window where the roof and window meeting all 4 sides

A skylight that is over 25 years old and only leaks during heavy rain is usually experiencing flashing failure rather than a roofing issue, especially if the surrounding shingles are still in good condition. The best long-term solution is to remove the shingles around the skylight, inspect the curb and flashing system, install new ice & water shield, and replace the flashing. Simply applying caulking is usually a temporary fix and often fails again after a short period. Since the skylight is already 25+ years old, it may also be worth considering a full skylight replacement. The cost difference between a major flashing repair and a new skylight is often not as large as homeowners expect, and a replacement provides a much longer service life and better energy efficiency. A site inspection would be needed to determine whether the leak is coming from the flashing, the skylight frame, or the glass seal itself. Best of luck with your project.

Jericho from Centaur Roofing Specialists. The best fix is to call us to come and check to see which type of skylight it is and to see if the skylight has the proper flashing or proper sealing kit installed with it. We normally reseal the glass to the frame and reseal the frame of the skylight. What type of skylight do you have? Is it a velux skylight with a flashing kit installed wrong by the last roofer to touch it, is it a curb mounted skylight with flashing around it ie it has a front dormer flashing, step flashings covered with cloak flashing on the side with a skylight back pan or is the skylight a low profile self flashing cheap skylight with ice & watershield installed on the 2 sides and upper back side with a low profile metal back pan on it?

A skylight that is over 25 years old and has started leaking during heavy rain is often nearing the end of its service life. Before deciding on a repair, it’s important to determine whether the leak is coming from the skylight itself, the flashing around it, or the surrounding roofing materials. In most cases, the best long-term solution is to replace the skylight and install new flashing rather than relying on caulking or patch repairs. Temporary sealants may stop the leak for a short time, but they rarely address the underlying issue and often fail again within a few seasons. Recommended approach 1. Have the skylight and flashing inspected from both the roof and interior. 2. If the skylight frame, glazing seals, or flashing are deteriorated, replace the entire unit. 3. Install a modern skylight with a manufacturer-approved flashing kit and proper ice-and-water shield around the opening. 4. If the skylight itself is in excellent condition and the leak is confirmed to be flashing-related, a professional re-flashing may be sufficient. Given the age of the unit (25+ years), replacement is usually the most cost-effective and reliable option compared to repeated repairs. A qualified roofing contractor should be able to confirm the source of the leak and provide options for either re-flashing or full replacement.