Integrated solar panels

Integrated solar panels are an alternative to conventional roof-mounted solar panels, as they sit flush with the surrounding roof tiles, rather than being mounted upon them. Some homeowners may prefer integrated solar panels over conventional panels, as they are generally considered to be more aesthetically pleasing than their roof-mounted counterparts, but they do require a new roof to be fitted at the same time.

However, integrated panels lack an air gap beneath each panel that conventional solar systems do have. This means integrated options can be less efficient, as they cannot be cooled by local air currents in the same way. Here, we break down the benefits and disadvantages of integrated solar panels, so you can make an informed decision.

What are roof-integrated solar panels?

Integrated solar panels, also known as in-roof solar panels, differ from conventional solar panels in that they are integrated into the roof rather than being mounted on top of the tiles or slates in a frame. 

This means that integrated solar panels actually replace a section of roof, with no roof tiles beneath the panels. Because of this, they have to be weatherproof and just as strong as normal roof tiles while also incorporating photovoltaic cells in order to generate electricity in the same way conventional solar panels do. 

Some people regard conventional solar panels as unsightly because they use mounts and clamps to attach the solar panel array to the roof. If that is you, you might want to consider integrated solar panels, as they sit flush with the roof tiles and they blend into it. A more aesthetically attractive solar panel array could be a big advantage on a listed building, or when it comes to selling your home.

Benefits of in-roof solar panels

Integrated solar panels have some advantages over conventional ones, including:

• Their weight on the roof. Installing conventional solar panels on top of the roof tiles adds to the weight that the roof has to bear, which in turn might cause repair issues over the long-term. However, given that integrated solar panels do not need a mounting frame and are instead installed flush with the roof tiles, there is no additional weight for the roof beams to bear. This is particularly good news for older homes where the roof beams may struggle to carry the weight of a solar panel array.

• Their discreet design. Integrated solar panels sit flush with the roof tiles and not obviously mounted on a frame, making them stand out less next to the rest of your home. This could add to the value of the property when it comes to selling it. The fact that these panels blend into your home more easily also makes them a great choice for listed buildings or homes in conservation areas. 

• Their weather resistance. Given that integrated solar panels are flush with the roof, they are less susceptible to damage in high winds than conventional solar panels, which have frames and various other components that can be damaged. Integrated solar panels also don’t need the gap beneath the panels that conventional panels do, which can be attractive to birds as potential nesting sites and cause damage. 

• Their cost. Integrated solar panels are now generally as affordable as conventional solar panels, which has encouraged solar panel manufacturers to offer more integrated solar panel options.

Disadvantages of integrated solar panels

While they are a great option for listed homes and design-conscious homeowners, there are some drawbacks to integrated solar panels: 

• They are generally less efficient than conventional solar panels, around 3 percent less efficient than the best solar panels to be precise. The main reason for this is that they are flush with the roof tiles which means they can’t take advantage of surrounding air currents in the way that conventional solar panel arrays can to keep the panels cool. This lower efficiency means that seeing a return on the initial investment will take a bit longer as there will be slightly less electricity being generated.

• Installing integrated solar panels as part of a retrofit to the roof will be somewhat more difficult than installing conventional panels. This is because of the more complex design but also because the installer will need to remove some of the surrounding roof tiles or slates as part of the process, which will cost more than installing the equivalent standard panels.

• Integrated solar panels are not suitable for all types of roof: they are best suited to roofs with a slope between 12° and 50°. While conventional solar panels can easily be adjusted in order to achieve the best angle and direction, integrated solar panels have to be installed at the same angle as the roof they are integrated into, which will in turn affect their efficiency.

Why should you choose integrated solar panels over standard ones?

One of the main reasons to opt for integrated solar panels rather than conventional panels is their subtlety, particularly in areas where obtaining planning permission might be a problem. Their design makes them easier to blend into the roof of your home. 

Retrofitting a roof is another circumstance in which integrated solar panels might be a better option as they require the removal of some of the tiles in your roof to be installed.  

How much do integrated solar panels cost?

Integrated solar panels used to be much more expensive than the traditional cost of solar panels, but they are now equivalent, usually between £7,100 to £9,100 for the 10 panels required to power the average UK home. The main difference in costs lies in the fact that for integrated solar panels, you may have to remove your roof tiles to install the panels. 

How do you install an integrated solar panel?

The ideal time to install integrated solar panels is when the roof needs replacing or repairing, or as part of a retrofit of the property generally, given that the roof tiles will need to be removed.

The solar panel installer needs to access the felt and batten layer of the roof, which is harder to do on older roofs or roofs with an unconventional shape. Having removed the roof tiles, the installer fits plastic trays on top of the felt and batten layer. The solar panels are then inserted into these plastic trays and wired into the building’s electricity system. Some panel arrays will also have weatherproof flashing inserted around the frame, but any gaps will more generally have tiles or slates inserted.

The installation process should take about two weeks if roof tiles need to be removed, compared to about two days for a mounted solar panel array. The process generally requires installers and roofing contractors to work together – the installers install the panels while the roofers subsequently fix the roofing tiles in the gaps around the newly-installed array.