How it works
How solar goes on a slate roof — nothing removed, nothing loaded.
Yes — solar can go on a slate roof. The patented SlatePlate™ mounting system installs between the existing slate courses and is designed to shed water and transfer the array’s weight into the roof structure, not the slate. Solar Slate Solutions makes SlatePlate and installs the slate mounting; your solar installer sets the panels, wiring, and permitting. Here is the method, step by step.
Patented slate-roof mounting system (U.S. & E.U.) · installs over your existing slate · designed to keep the roof weather-tight
The method
Nine steps, one attachment point.
Every solar mount is one attachment point. This is what happens at each one — in order, following the SlatePlate installation guide. This is the mounting method; your solar installer sets the PV panels, wiring, and electrical. Dimensions and part numbers live on the SlatePlate product page.
1
Find the rafters, plan the layout
The installer locates the roof’s structural members and sets each mounting location to the array’s engineering plan and to local & state ICC codes.
2
Mark with the template
A supplied template guides the exact drill points and the outline of the notch.
3
Drill the pilot hole
A center pilot is drilled to avoid damaging the structural member — this is where the lag bolt and L-Mount anchor. A 3/16″ (4.5 mm) pilot guides the 5/16″ (8 mm) stainless lag.
4
Respect the slate
Slide a small flat bar under the slate before drilling — this protects the slate underneath.
5
Relieve and grind the notch
Two 5/16″ (8 mm) relief holes are drilled at the notch’s top corners, then a diamond wheel grinds the notch into the top slate — stopping at the two points so the slate scores cleanly rather than fractures.
6
Open the path to the deck
A masonry hole saw bores a clean opening through the slate down to the roof sheathing, exposing the wood deck at the mount point. A 1″ (25 mm) masonry hole saw, pilot-guided, reaches the sheathing.
7
Test-fit and cut the plate
The SlatePlate is slid up until it meets the nails of the slate above, then marked and cut to length. The Spacer and Adjuster are dry-fit so everything seats before sealing.
8
Seal and set the mount
The cavity is filled with sealant just below flush, the Spacer is inserted, then SlatePlate is slid into place.
9
Lock the plate, finish weather-tight
Secure your preferred L-Mount with the supplied 5/16 × 6″ stainless structural lag and butyl washer.
Looking for dimensions, materials, and part numbers? Those live on the SlatePlate product page — this page covers the method, so the technical spec sheet stays in one place.
Why it protects the slate
The slate isn’t clamped or loaded, by design.
Built for slate, not shingles
Standard solar hardware is made for asphalt shingles — it clamps or drives fasteners in ways that put point loads on the roofing surface. On slate, that is exactly how tiles crack. SlatePlate is designed around a different idea: carry the weight past the tile.
A load path to the structure
The plate, base-with-notch, and spacer are designed to form a load path from the L-Mount straight down through the stainless lag into the structural member below. The notch-and-spacer geometry means the natural slate seats against the plate rather than bearing the panel’s weight.
Protected, not sacrificed
The result, by design, is solar mounted with the slate protected — not sacrificed to hold the array up. The natural slate seats tight against the plate and laps back over it, so the roof keeps its look and keeps shedding water.
The load path, in order:
- Panel & rail — standard racking lands on the L-Mount, as it would on any roof.
- L-Mount & lag bolt — the stainless lag is designed to carry the load into the structural member.
- SlatePlate + spacer — transfers and locks the assembly; by design, the slate isn’t part of the load path.
- Natural slate — seats tight against the plate and laps back over it: protected, not clamped.
See it on the roof
Watch a full SlatePlate install.
The step-by-step method is one thing to read and another to watch. Field-capture footage of a complete attachment point will play here.
What to expect
Who does the work — and what stays the same.
The important part is who is on the roof, that the job is done to code, and that the roof is weather-tight when the crew leaves.
Who installs it
A solar installer trained on the SlatePlate method, or the Solar Slate Solutions crew for the slate mounting. Either way, it’s people set up to work on slate — not a shingle crew improvising. Your solar installer handles the panels, wiring, and permitting.
Built to code
Mount locations and the array follow the project engineering and local & state ICC codes — the same permitting and inspection path any compliant solar install goes through.
Roof stays weather-tight
Each penetration is sealed and flashed, and the slate above laps back over the plate, so the detail is designed to keep the roof shedding water the way it always has when the crew leaves.
Curious how fast each mount goes in? The average per-unit install time with our teams is being confirmed before we publish a figure — but the founder has installed 4 mounts, on a ladder, in under 13 minutes. We’d rather show you the method than quote a number.
The honest concerns
The things people worry about.
“Will it leak?”
Each mount is sealed in the cavity, set with a butyl/stainless washer, and the plate seats tight to the slate — finished with your preferred “L” mount. The detail is designed to close the penetration, not leave it open.
“Are you removing my slate?”
Courses of slate aren’t removed to mount the array. A small notch in the slate is made at each anchor point; the slate above laps back over the plate and stays part of the roof.
“Is it up to code?”
Mount locations follow the project engineering and local & state ICC codes — the same code path as any permitted solar installation.
“Will it work with my installer’s racking?”
SlatePlate anchors a standard L-Mount, so the installer’s usual rail lands on the mount as it would on any roof. It works with most single-hole L-Mounts; your installer confirms compatibility for your system.
The how & can questions
Solar on a slate roof, answered.
Can you really put solar on a slate roof?
Yes. Slate is brittle and standard mounting risks cracking it, which is why many installers decline slate-roof jobs. SlatePlate is a patented mounting system that lets solar panels be installed on slate roofs — designed to transfer the array’s load into the roof structure, not the brittle slate.
Will it crack or damage the slate?
The method is built to avoid it. The notch is scored between two relief holes so the slate breaks cleanly rather than fracturing, and the finished mount seats against the slate instead of clamping or loading it. The slate is not part of what holds the panels up.
Does the roof stay waterproof?
Each penetration is sealed in the cavity, set with a butyl/stainless washer, and finished with flashing (copper preferred). The slate above laps back over the plate, so the detail is designed to keep the roof shedding water the way a slate roof is meant to.
Who installs it?
A solar installer trained on the SlatePlate method, or the Solar Slate Solutions crew for the slate mounting — people set up to work on slate. Your solar installer sets the panels, wiring, and permitting. Layout and mounting follow the project engineering and local & state ICC codes.
What racking does it work with?
SlatePlate anchors a standard L-Mount (single-hole preferred), so it works with most mainstream rail systems the installer already uses. The confirmed compatible-racking list is being finalized.
For installers, roofers & EPCs
The questions the trade asks.
Who carries liability if a slate cracks or the roof leaks?
Responsibility follows the installation contract and the SlatePlate product warranty. The method is designed to seat against the slate rather than clamp or load it, and each penetration is sealed and flashed. Confirm coverage on the warranty page.
What is the callback / leak track record?
Each mount is sealed in the cavity, set with a butyl/stainless washer, and finished with flashing, and the design keeps the load off the slate. We won’t publish a callback or leak-rate figure until it is verified.
How long does each mount take, and how do I bid the labor?
The method is the eight-step sequence above, repeated at each attachment point. We’re confirming a per-unit install time before publishing one, so bid from your own crew’s trial on the method rather than a number we can’t yet stand behind.
How does an installer get trained or become a dealer?
Installers can be trained on the SlatePlate method, and there is an installer and dealer path. Contact us to discuss training and distribution for your territory.
Keep exploring
Related pages
SlatePlate — the part that makes it possible
Dimensions, materials, part numbers, patents, and the wind-driven-rain testing behind the mount. See the SlatePlate specs →
Warranty & coverage
What’s covered on the SlatePlate mounting system, and how to register your installation. Read the warranty →
Solar installers
How we train and supply installers on the method so your crew can take on slate with confidence. For solar installers →
Talk to a slate-solar specialist.
Patented slate-roof mounting — and a straight answer about your roof.
Send photos of your slate roof for a feasibility review, or ask how the method applies to your project. A real person answers.
Solar Slate Solutions, LLC · Mon–Fri 9–5 · Sat 9–1 · Sun closed
A documented sequence
How it works
Six steps — not improvisation on a fragile roof.
