Installing Solar on an Old Spanish Tile Roof

This page preserves the original ABC Solar photo sequence for old Spanish tile roofs, rebuilt with a modern, mobile-first layout. The core idea is simple: remove tile where needed (weight + waterproofing), mount to structure, waterproof aggressively, then build straight rails and a clean array.

Weight managedold tile can be very heavy per sq. ft.

Roof stays a roofpenetrations sealed correctly

Clean finishstraight rails + aligned array

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1) Removing Tile (weight + waterproofing)

The primary reason for removing old Spanish tile from under the solar installation is weight. Old Spanish tiles can weigh up to 14 lbs per square foot.

The other reason is to ensure a 100% waterproof installation. On our retrofit solar installations, mounting feet are installed by a licensed roofer.

The feet are mounted to house a solar rail which then houses the solar electric panels. Typical layout allows ~2' of overrun at the ends and ~4' to 6' for an entire row span (project-dependent).

Tile removed where needed Rafter hit Roof-first mindset

Old Spanish tile removed to reduce weight and prepare roof plane for solar installation. — Old tile removed in the array area: weight reduction and waterproof-first preparation.

Roofing crew working on underlayment / composition layer after tile removal for solar installation. — Underlayment/composition layer staged after tile removal—set up for a long-term waterproof install.

2) Waterproofing (do it like you mean it)

We use standard roofing penetration waterproofing materials, including Henry’s and tacky tape. Waterproofing is also achieved by laying the composition roofing material correctly.

Mount risers and sealed penetration points visible on newly laid composition surface under the former tile area. — Penetrations dressed and sealed on the composed surface—this is where roof quality is won or lost.

3) Feeder Drill Holes + Structural Fastening

Once the rafters and the layout of the feet are determined, we drill feeder holes to make bolting the feet to the rafter smoother, safer, and stronger.

Typical hardware (as documented in the original page): 5/16" x 3" lag screws per mounting foot. (Final specs can vary by engineering and site conditions.)

Rails staged across roof with mounts/risers in place on the prepared roof plane. — Mounts/risers set; rails staged and aligned before final fastening.

4) Solar Rails Attach to Solar Mounts

Rails are laid along the mounts to check distance and straightness. Panel count is calculated by width/height depending on portrait vs landscape orientation (including a bit of room for mounting hardware).

The rails are drilled above each mount and attached with washer and bolt.

Crew preparing to set the first module with rails installed on the old Spanish tile roof area. — Rails set: alignment checked before the array goes on.

Module being positioned on rails during installation. — First modules on: straight rails make the finish look intentional.

5) Solar Panels Attached to Rails (wire + finish)

As modules attach to the rails, they’re typically wired in series to increase voltage. On the original documented install: 22 panels, separated into two strings of 11. The two strings are then paralleled and wired to the DC/AC grid-tie inverter.

Completed solar array installed on an old Spanish tile roof (tile remaining on adjacent roof areas). — Completed array: clean edge, straight lines, and a roof that still functions as a roof.

Mehlberg Solar Estate (Palos Verdes Estates) →

First consideration: picking the best roof face

The first consideration for any solar installation is selecting the best roof plane. Key factors include shading from trees and chimneys, plus the conduit run from the array to the main electrical panel.

The best-looking system is the one that’s designed correctly from the start.