Skylight Installation in Mill Valley, CA

What Skylight Installation Involves

Skylight installation is more than cutting a hole and dropping in a window. It requires removing the existing shingles in a rectangular patch, cutting the roof deck cleanly between rafters, and building a curb to raise the skylight above the roofline. We then set the unit on a bed of self-adhered ice-and-water shield, fasten it with ring-shank nails, and hand-seal every exposed fastener. The flashing—whether step flashing on a sloped roof or a custom pan on a flat one—gets integrated into the surrounding field course so water sheds naturally.

For a typical Mill Valley home, the opening is framed with 2x6 lumber, then insulated and drywalled from below. We install the skylight itself, which can be fixed or venting. Venting units include a motorized or manual crank that opens the glass for airflow. We also run a low-voltage wire for the rain sensor that closes the skylight automatically when it starts to sprinkle. That matters here, where a sunny morning can turn to drizzle by noon.

Materials and Options We Offer

We install three main types of skylights: fixed, venting, and tubular. Fixed units are the least expensive and most reliable—no moving parts, just light. Venting units cost more but let you pull warm air out of a kitchen or bathroom. Tubular skylights are small, flexible tubes that bounce sunlight down a reflective shaft; they suit hallways and closets where a full-size unit won't fit.

Glass matters more than the frame. We use double-pane, low-E glass with argon gas between the panes. That cuts heat loss in winter and keeps UV rays from fading your floors. The frame is either aluminum with a baked-on finish or a wood-clad interior. Aluminum resists corrosion from the salt air that blows in from the Pacific, but wood looks warmer from inside. We'll help you choose based on your ceiling style and your budget.

For the roof penetration, we use a curb-mounted design on low-slope roofs and a deck-mounted design on steeper pitches. The deck-mounted style sits flush with the shingles, which looks cleaner but requires more careful flashing. On a 6/12 pitch—common in Cascade and Homestead Valley—we'll typically use step flashing and a continuous head flashing that we tuck under the siding. Every joint gets a bead of polyurethane sealant, not the cheap acrylic stuff that cracks in a season.

Signs You Need Skylight Installation

You might need skylight installation if a room feels dark and closed in, especially on the north side of your home where the fog lingers. If you're already replacing your roof, that's the ideal time to add a skylight—the tear-off exposes the deck, so the extra work costs less than doing it later. Water stains on your ceiling near an existing skylight mean the old unit's flashing has failed; we can replace the whole assembly before rot spreads to the rafters.

Other signs: your current skylight is single-pane and fogs up between the glass, or the seal has failed and you hear wind whistling through the frame. If the curb has settled or the flashing has pulled away from the roof, water will wick along the decking and erode the plywood. Catching it early saves you from a bigger repair later.

Our Step-by-Step Process

1. Inspection and Layout: We measure your attic to confirm rafter spacing and check for any existing rot or decay. We mark the opening from inside and outside, making sure the skylight lands between rafters—if it doesn't, we'll frame a new header.
2. Roof Prep: We strip the shingles in the work area, cut the deck with a circular saw set to the sheathing depth, and install the curb or deck-mounted frame. We set the unit in a bed of self-adhered underlayment, wrapping it up the sides of the curb.
3. Flashing and Shingling: We integrate the skylight into the roof's staggered courses. Step flashing goes on each side, and a head flashing caps the top. We back-nail the flashing and hand-seal the exposed fasteners. The field course is relayed around the unit so the roof looks continuous.
4. Interior Finish: We insulate the shaft with rigid foam, then drywall and tape it. We install the interior trim and, if it's a venting unit, wire the motor and rain sensor. We leave the space clean and ready for paint.
5. Final Test: We run water over the skylight with a hose to confirm the flashing sheds properly. We check the seal from inside and make sure the vent operates smoothly. We also take photos for your records and ours.

The whole job typically takes one to two days, depending on whether we're also repairing the roof deck. We pull any needed permits with the City of Mill Valley—that's part of our service. We also warranty our workmanship for 10 years, which covers the flashing and installation, separate from the manufacturer's glass warranty.

Cost Ranges for Mill Valley

Skylight installation costs between $1,200 and $2,500 per unit, installed, for a standard fixed skylight on a shingle roof. Venting units run $1,800 to $3,200. Tubular skylights are the budget option at $800 to $1,200. The price varies with your roof pitch, the number of stories, and whether we need to frame a new opening or just replace an existing one. Add $200 to $400 if the roof deck needs repair—we'll tell you before we start, not after.

We give free, itemized estimates with no pressure. We'll walk your roof, measure the opening, and quote the exact scope. If you're in Alto or Strawberry, where the roofs tend to be steep and the access tight, we'll factor in the extra labor. For a two-story home, we use a lift rather than a ladder—safer for our crew and faster for you.

Local Climate Considerations

Mill Valley's fog and winter rains make skylight flashing the most critical part of the job. The constant moisture from the Pacific means any exposed fastener will corrode if not sealed. We use stainless steel screws and ring-shank nails—they hold better in the coastal humidity and resist the salt spray that blows over Mount Tamalpais.

We also recommend low-E glass to control heat gain. Our summers are mild, but the sun can still beat down through a south-facing skylight. The low-E coating reflects that heat while letting light in. In winter, the argon gas keeps the warmth inside. You'll notice a difference on your energy bill—and your plants will thank you for the steady light.

Warranty and Insurance

Every skylight we install comes with a 10-year workmanship warranty on the flashing and installation. The manufacturer covers the glass and frame for 20 years. We're fully licensed and insured, so you're protected if anything goes wrong during the job. We also register the warranty with the manufacturer, so if you sell your home, the coverage transfers to the new owner.

We're a Mill Valley roofing contractor with a track record in this town. We've replaced roofs in Homestead Valley, Muir Beach, and everywhere in between. When you hire us, you get a crew that knows how to work around the fog schedule—we plan for the rain and finish before it hits.