How Solar Panels are fitted to roof tiles

How Solar Panels are fitted to roof tiles

Do you know how solar panels are attached to roofs with tiles? 

Most people have no clue how their solar panels get attached to the roof.  

There are many things to consider and in this article we will show you how they should be fitted.

All the examples here are for a concrete pan tile roof.  Other roof types have similar methods, but also some key differences.   

Keep on reading to find out what you should and shouldn’t do to install solar panels on tiled roofs. 

The basic roof installation

For the most basic of explanations, a solar panel is fitted to the roof with a hook and rail system designed for the type of roof and tile. 

There will be a hook of some sort, that gets installed to the timbers in the roof. There are lots of brands that make these hooks.  They mostly all do the same job.   

These hooks carry a rail, and it is this rail that the solar panels sit on.  Rails are often silver but you also find black rails. 

To finish off, Solar Panels are attached to the rails using clamps. Some systems use a universal clamp while others have different middle and end clamps.  

Additional finishing touches are added such as rail end caps, bird protection and cable ties for the cables.

It’s all fairly straightforward, but amazingly common that poor installations are carried out.  This is usually due to a lack of skill or knowledge from the installers.  

Now you know the basics, continue reading to learn more about the details and see how this all comes together step by step. 

How solar panels are fitted to roofs
Vertical roof rails getting installed

WHAT DO MCS SAY?

PV systems should not adversely affect the weather tightness or structural integrity of the building to which they are fitted. The system should be designed and installed to ensure this is maintained for the life of the system.

Section 11.4.1 in the Code of Practice states that roof brackets used to fix a PV system to a slate or tiled roof shall not impose any load on the slates or tiles.  

Where necessary to ensure rooftiles or slates are not displaced creating gaps greater than those pre-existing the installation, then those tiles or slates shall be notched or flashed as appropriate.

Step 1. Installing the roof hooks

The first step when installing solar panels on your roof is to fix the roof hooks to the roof structure.  In most modern properties this is likely to be a Trussed Rafter arrangement, or Rafters and Purlins.  Many other types of roofs exist, but for this guide, these are the most common types found in the UK when dealing with a concrete pan tile. 

We start by exposing the felt and batons by lifting some tiles to locate the rafters.  

Once they have been found, the roof is measured and the most suitable mounting positions are selected.  

This is usually every other rafter but can vary depending on spacings and roof design.  The number of panels, weight of the mounting system as well as wind speed for the area will all affect the number and locations of the roof hooks. 

Once the locations have been decided, the hooks get fixed to the rafters using their supplied screws.  The Hook + Fixing are designed to work together and must always be correctly installed. 

@elecinn See how the solar panels attach to the roof. Stu is installing this system ready for 14 All Black Panels to get fitted to this house in Findern, Derby. #Solar #SolarPV #SolarPVInstaller #SolarInstaller #Renewables #GreenEnergy #SolarPanels #HomeSolarPanels #SolarPanelInstaller #SolarPower #Battery #batterystorage ♬ Standout - Kid Dean

Step 2. Grinding and re-fitting the tiles

A very important thing to remember is that installing Solar PV to your property should not in any way impact the effectiveness of the roof.

It must remain water tight and weather resistant. 

The way to do this is by ensuring the tiles fit correctly over the brackets.  Grinding the tiles to make space for the brackets is how we ensure the roof stays watertight. 

Some tiles system need a different method, but the concrete pan tile just needs a small slot grinding out.  this does not effect the strength of the tile and is the MCS approved installation method. 

Step 3. Fitting the rails

Installing the rails to hold the solar panels is often the easiest and most satisfying part of the installation. 

There is something about bolting down the rail and preparing for the panels that is great to see. 

Roof hooks have a nut and bolt system that allows the rail to securly fasten down, and also adjust the alignment.

pan tile roof rails for solar installation

Step 4. Fitting the Solar Panels

This is where the fun begins. The Solar Panels are ready to fit.  The panels lay down on the rails and are held into place by clamps.

The clamps secure the solar panels to the rails and are bolted down in a way that also keeps the panels in a uniform arrangement with all the spaces equal.  

One thing to look out for here is to ensure the cables are not trapped by the brackets.  It’s also important to secure the cables to the rails as you install the panels.

Step 5. Finishing off

All this is left to do is tidy up the system, clipping cables and adding endcaps. 

We always install bird protection, so that goes on last of all.  

Now you know what’s involved with the roof installation you have a better idea of the question to ask your solar panel installers. 

If you want to find out more about Solar Panel installations then keep reading our blog for lot more posts about Solar. 

If you are ready for a quote then get in touch using the contact button below.