Grinding Roof Tiles Leaves A Giant Solar Mess

You might have noticed that grinding artificial stone kitchen benchtops was banned in 2024.

Health and safety laws have caught up with the silica dust created when grinding cement products, and for solar installation that means dry grinding tiles is no longer acceptable.

Solar Installation That Grinds My Gears

Recently I fielded a complaint from a punter and it was disappointing for everyone concerned.

The installer had lifted a few tiles, ground them for bracket clearance and screwed the system on with great efficiency. Problem was that the homeowner had recently paid good money to vacuum all the dirt and dust from the roof space and installed new bulk insulation.

This work was laid to waste because the new insulation was now filled with concrete dust & tile fragments.

What a mess.

Dear SQ,

I don’t have anyone qualified/experienced to ask to get some advice on what is/isn’t acceptable practices for solar installation. I don’t know if I’m being unreasonable or if this is a real issue I need to pursue.

They cut my concrete roof tiles in-situ (still on the roof) to install the brackets, used no dust control and filled my house with concrete dust – in the roof cavity and some inside the house itself.

Picture is of garage that has no ceiling – so all dust created above it fell on the floor. The rest of the roof cavity has significantly more brackets and more dust. It is a LOT of dust, the picture does not do it justice – please refer to video.

I installed new roof insulation literally last week and now it is as dusty and in as poor condition as the old stuff I removed – getting rid of the dust out of my roof cavity was entirely the point of that exercise. I am frustrated.

As mentioned, hoping to get some guidance or advice on what is reasonable in this situation. It’s out of my wheelhouse.It would be good to know if I am being an unreasonable customer or if I am within my rights to be upset.

Kind regards,

Aanon

Rules Require Tiles Are Modified

Some of the installers I’ve worked for took a fairly libertarian approach to the rules – they ignored them. Bang the brackets in, slide the tile back down and get on with the job.

Green arrow shows where tile isn’t fitted properly. Bonus sharp edges to damage DC array wiring arrowed in red.

Apparently none of them leaked, except the 100kW – 300 panels on a pub. A disaster that was only fixed by removing the solar altogether because the roof pitch was always too low.

These days, everyone must make sure the tiles sit back exactly where they were, which means making space for the bracket.

The bracket circled is quite narrow so the green shaded section needs to come out, not the whole bottom edge shaded red.

There’s variations on method but many installers would prop a tile up on their boot and poke a 9” grinder under the chosen area to blindly carve ribs off the bottom of the tile. A classic quick and dirty way to get through the day – I suspect that’s what caused this particular complaint.

I’ve personally marked, flipped and ground tiles with a 5” wheel for a closer fit, which at least left the detritus on top of the roof, rather than on top of the ceiling. It was still a filthy job.

Different tiles need different approaches.

Compliant Works

For many the best way is to use a scutch hammer. With a few deft blows you can get a reasonable fit without making any dust and it’s probably just as quick as flipping and grinding once you have practice. However it’s not always going to be neat and in some instances may not work, such as when you have to modify both top and bottom of thin terracotta tiles.

Terror-cotta is an installer’s nightmare in many cases.

Wet grinding is the best but creates its own issues. Tiles need to be marked, numbered, dragged off the roof and processed where you clean up a mess afterward. At a pinch your cardboard solar panel carton would contain the spray and slurry, but effectively this is the same operation needed to cut pavers or bricks.

Regardless I would always recommend a wet diamond holesaw for electrical penetration.

Making a clean hole in a 70-year-old tile without smashing it.

Tiles Are A Joke Really

The whole concept of building a house strong enough to support a roof of broken masonry just beggars belief. If it wasn’t already considered normal, tiles would never get up as a new idea.

The best roof penetration I know of is a gland fitting made by Cobalt.

If you have problems with your tile roof and it needs money spent on a restoration, you’re best to simply do away with it. Throw the tiles in the bin, insulate the house while they’re off, and then reclad with iron. It’s stronger, lighter and longer lasting, plus cheaper to install more solar.

If you found a SolarQuotes installer making holes like this rubbish, I want to know.

Maintaining Quality

I’ve often tried to explain to people that SolarQuotes isn’t just a customer acquisition process. We don’t just collate names and addresses; we offer a third-party guarantee to the consumer and offer business coaching and quality assurance for the installers.

This shows how the bracket is supposed to be let into the underside of the tile. The tile broke when an installer stepped on it because it hadn’t been ground out.

So when we bring a new installer onboard we make sure they understand that phone calls are expensive.

2009 takes me back. Notice that two tiles are displaced by one bracket.

Customers are comfortable contacting us with concerns they think might be trivial. When these emails turn out to be real complaints, my phone rings, then the installer’s phone rings, and then there’s some soul-searching and sadness all around.

Some Customers Are Psychos

Not every complaint I answer is from a rational human being. Some of them get their own article, others send us photos they’ve acquired from installers during court cases they’ve already lost. That’s a story for another day.

In most cases, we get to assure the customer they’ve already got a good job, or we arrange a return visit for the installer to correct some problems, however honest or embarrassing. We’ve paid for some third-party audits, but after hundreds of thousands of installations, we’ve shelled out for less than a handful of rectifications. The system works.

In 2008, we were using handmade tile brackets and a bespoke frame to span straight over the low-pitched extension here. The customer specifically wanted to shed water off what was already a somewhat leaky roof.

This Has Cropped Up More Than Once

In this case, the installer has come to an arrangement with the customer, but my advice is generally that an electrician will spend time more profitably doing electrical work. So long as the solar company has learnt a lesson, we mark it down on their file and explain that the best people to make good on a problem like this are the insulation industry.

However, the best option is always to have a discussion with your trades before install day.

To find a quality installer in your neighbourhood who won’t leave a filthy mess, put your postcode into our Solar Installers Near Me page.