repairman with measuring tape next to a skylight

While it would be great if skylights could last a lifetime, the unfortunate truth is they have a limited service life.  

Skylights will typically need replacing every eight to 15 years, but homeowners can run into various situations that require replacing them much sooner. 

Regardless of how many years they've had their skylight, many people question if replacing it when they put in a new roof is the right move. The short answer is yes. 

In the long run, you benefit from replacing your skylight when you re-roof, and the first step is making sure you know how to measure a skylight correctly. 

Check the Model

The number one brand for residential skylights, without a doubt, is VELUX. But like the Apple lineup, it comes in different models and sizes. 

Depending on the type of VELUX skylight you have, the ID tag with its specifications will vary. The tags in the deck-mounted skylight are located on the frame's interior, while the curb-mounted skylights have it stamped along the exterior of any of the four sides. 

If you have a roof window, then the ID tag is located on the interior of the ventilation flap. When the tag can't be found, you can identify the model with the VELTERM number on the spacer bar between the glass panes.  

New to Replacing Your Residential Skylights? Find Them Here!

dreamy outdoor covered patio

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Measuring Deck-Mounted Skylights

After identifying your old skylight with the ID tag or VELTERM number, you still need to measure it – regardless of whether you're replacing the entire product or ordering a skylight dome replacement

The first step is to measure the glass's exterior length and then the width of the glass from the interior of the cladding. It's important to get this correct because of the different drywall grooves with new skylight models. 

This can cause differences requiring trimming the drywall panel down or to fill in any gaps using molding or painter's caulk. 

For any non-VELUX deck-mounted skylights, there's an added step of measuring the opening length and width of the drywall inside the house and measuring the entire skylight, including the cladding. 

Measuring Curb-Mounted Skylights

Like deck-mounted skylights, you'll want to measure the width of the exterior glass from the cladding interior and measure the outside length of the glass. The additional step here is to ensure your outside length measurements of the glass include the flashing. 

If you run into trouble with measurements or want to ensure it's done correctly, contact our specialists to ensure you get it done right the first time. 

Replacing the Dome

Sometimes, a skylight doesn't require replacing the entire thing. If you see any condensation forming or feel any air drafts, then you might only need to replace your skylight dome. 

Many people think of these as non-issues, but when these problems start appearing, it's likely that the glass will soon experience cracks or even leaks. And that presents a significant problem.

When you see small cracks or leaks, it's time to get it replaced ASAP before it causes structural problems for the surrounding areas. 

Upgrade Your Home with a Skylight Dome Replacement

skylight window waterproofing installation

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Replacing Your Skylight

If you're replacing your skylight because of a new roof installation, you must protect it with proper flashing. This is important because if the flashing is installed haphazardly, you're guaranteed to experience leaks in the near future. 

Replacing your skylight doesn't have to induce headaches or be a frustrating experience. Our specialists are here to guide you on how to install a skylight

If you're wondering if it's time to replace your skylight or if you run into any problems with installing it, then call our specialists at (888) 866-1149 for a professional, hassle-free experience.