Seeking Natural Light? Compare Skylight Mounting Methods

Installing a skylight can make a dramatic difference in any home or room by allowing beautiful natural light to fill the space. Skylights come in many shapes, sizes and designs, but one of the most important considerations is how the skylight will be mounted and installed.

There are two main methods for mounting skylights: curb mounted or deck mounted. Understanding the key differences between these two mounting techniques will help you choose the best option for your home and roof type.

Curb Mounted Skylights

A curb mounted skylight is installed on top of a raised wooden frame or "curb" that attaches to the roof deck. The skylight itself sits on top of this frame, which raises it above the surface of the roof.

Here are some of the benefits and drawbacks of choosing curb mounted skylights:

Pros of Curb Mounted Skylights

• Ideal for flat or gently sloping roofs where a curb raises the skylight to allow for proper drainage
• The raised curb provides excellent protection against leaks by elevating the skylight above the roof
• More customizable options for shape and size to fit your design needs

Cons of Curb Mounted Skylights

• More expensive to purchase and install due to materials and labor costs of constructing the curb
• Not recommended for very steeply pitched roofs where a curb would be impractical
• Harder to access for maintenance since you need to climb up the curb frame

Overall, the raised curb design of this mounting method lends itself better to low-angled roofs in climates with heavy precipitation. The curb provides an extra layer of weather protection and allows for excellent drainage on flat or gently sloping roofs.

Deck Mounted Skylights

In contrast to curb mounted models, deck mounted skylights are installed directly onto the roof deck or sheathing. The skylight frame is mounted flush with the surface of the roof and attached with screws driven into the roof deck.

Here are some of the most notable pros and cons of deck mounted skylights:

Pros of Deck Mounted Skylights

• Lower cost to purchase and install since no curb is required
• Ideal for steeper sloped roofs where a curb would not be practical
• Easier to access for maintenance from the roof compared to climbing a curb
• Sleek, low-profile look many homeowners prefer

Cons of Deck Mounted Skylights

• Not recommended for low-pitch roofs since drainage could be impaired
• Flush mount provides less weather protection compared to a raised curb
• Fewer shape and size options due to limitations of deck mounting

Overall, deck mounted skylights excel on steeper roofs where their low-profile, aerodynamic shape blends beautifully into the roofline. They cost less than curb mounted models, but do require careful flashing and weatherproofing on the roof for optimal leak protection.

Key Difference: Mounting Method

The main distinction between these two skylight mounting methods comes down to how the skylight unit is positioned and attached to the roof:

• Curb mounted skylights have a raised wooden frame surrounding the skylight and elevating it above the roofline.
• Deck mounted skylights sit flush against the roof surface and are screwed directly into the roof deck.

Beyond affecting appearance, the mounting technique also impacts weather resistance and accessibility:

• The raised curb on a curb mounted skylight provides excellent protection against wind-driven rain and snow infiltration.
• The low profile of a deck mounted skylight allows for easier access from the roof for cleaning and maintenance.

Which Mounting Method is Best for Your Roof?

When deciding between curb vs. deck mounting, the roof slope or pitch is a primary factor to consider:

• Curb mounted skylights are ideal for flat or gently sloping roofs with a pitch of 0-30 degrees.
• Deck mounted skylights are better suited for steeper roofs with a pitch of 30 degrees or greater.

On a low angle roof, a curb mounted skylight can raise the glass surface to allow for proper drainage. On a steeper pitch, a deck mounted model provides a sleek, low-profile look.

Other factors like roof materials, local weather patterns, and building codes may also influence which mounting method works best.

Cost Comparison of Curb vs. Deck Mounted

When comparing installation costs, deck mounted skylights tend to be less expensive than curb mounted models. The main reasons for the cost difference include:

• Curb mounted skylights require purchasing lumber and constructing a sturdy frame, which adds to material expenses.
• Building and waterproofing the skylight curb demands extensive labor by the installation team.
• Deck mounted skylights simply attach directly to the roof, eliminating the curb construction costs.

However, deck mounted skylights may require more complex flashing and weatherproofing around the roof opening to prevent leaks. Over the long run, routine maintenance costs end up being comparable for both mounting methods.

Appearance and Customization Options

Homeowners choosing curb mounted skylights enjoy more flexibility in terms of shape and size customization. The skylight builder can construct a curb in virtually any shape or dimensions to suit your space. Deck mounted models are more limited by the existing roof opening.

In terms of aesthetics, deck mounted skylights have a lower profile that many find attractive. They blend nicely into the slope of the roof. Curb mounted skylights stand out more prominently with their raised frame structure.

Another consideration is exterior visibility. The higher curb frame on a curb mounted skylight may be more visible from the ground, while a deck mounted skylight sits nearly flush with the roofline.

Accessibility and Maintenance

An important distinction between the two mounting methods is accessibility for cleaning and repairs. With deck mounted skylights, you can access the glass surface directly from the exterior roof.

On curb mounted models, ladders or scaffolding must be secured to the roof and curb frame to reach the skylight glass for cleaning. This makes routine maintenance more difficult and potentially hazardous.

The raised curb also accumulates leaves and debris, requiring more frequent cleaning. Overall, deck mounted skylights offer much easier access for DIY cleaning and maintenance.

Environmental Factors to Consider

Beyond roof pitch, key environmental factors like rainfall, snow, and temperature extremes can impact skylight selection. In cold climates, curb mounted models may be preferable since the curb sits above the roofline, preventing snow or ice buildup directly on the skylight.

In wet climates, the raised curb provides excellent protection against heavy rainfall or wind-driven rain coming in at an angle. Deck mounted skylights rely more on quality flashing and weatherstripping around the roof opening to prevent water intrusion.

Areas very prone to extreme heat, cold, or wind may necessitate choosing laminated or tempered glass skylights for strength. Consulting local building codes is always wise.

Making the Best Skylight Choice for Your Home

Ultimately, the ideal skylight mounting method for your home depends on several variables:

• Roof pitch and structure
• Climate and typical weather patterns in your area
• Desired appearance and visibility
• Accessibility for cleaning and maintenance
• Budget for the project

Carefully weighing the pros and cons of curb vs. deck mounting will lead you to the right solution. If unsure, partnering with an experienced skylight installer is invaluable for providing recommendations tailored to your roof and needs. Investing in the proper skylight model and mounting method leads to a lifetime of enjoying beautiful, natural light.

When installing a skylight, curb mounted and deck mounted are the two primary methods to choose from. Curb mounted models elevate the skylight on a raised frame, making them ideal for flat roofs. Deck mounted skylights cost less and excel on steeper pitches. Key factors like roof structure, climate, budget, and accessibility help determine the best mounting option.

A new skylight can provide many years of aesthetic beauty and energy-saving natural light with some careful planning. Partnering with an experienced skylight professional will ensure your project goes smoothly from start to finish.