FAQs

We recommend choosing the lightest grey *6mm thick* slates available in the range that you prefer.  The best matches we have seen to date are with the Cupa 12, Siga 37, Siga 39, Gallegas 37 & Gallegas 39, and the Cupa H3.  Other blue-grey slates including Welsh Cwt y Bugail (not Heather Blue), Cornish Delabole and La Concha will also blend well.  Natural slates with the words dark grey or black in their descriptions will contrast quite strongly with PV Slates.

Yes, the PV Slate received MCS accreditation in 2018. Contact us to discuss why this might be important for your project.

Each PV Slate weighs between 3.0-3.9kg depending on model. This means it weighs less than the natural slates it replaces so does not increase loading on the property or require any remedial strengthening, which is good news for listed buildings.

PV slate was specifically designed to help people in all restricted planning areas gain planning permission. Check the details with your local planning authority and we’re happy to assist where we can.

PV Slate can be fitted to pitches typically as low as 25 degrees. However, the lowest pitch can be steeper for more exposed locations.  Please contact us and we will advise on the correct PV Slate product for your roof pitch and location.  

PV Slate 600x300 is compatible with natural slates of 600x300x6mm (24”x12”).

PV Slate 500x300 is compatible with natural slates of 500x300x6mm (20”x12”).

PV Slate 500x250 is compatible with natural slates of 500x250x6mm (20”x10”).

Contact us to discuss tile/fibre cement slate compatibility.

Please send your architect’s drawings to us in an email to info@gb-sol.co.uk and we’ll be happy to calculate how many PV slates your roof can accommodate. If you don’t have these, please provide your roof dimensions and we’ll produce an estimate.

PV Slate 600x300: 4.2 per m2

PV Slate 500x300: 5.5 per m2

PV Slate 500x250: 5.0 per m2

As natural slates need to surround the PV slates, please contact us for an accurate number of PV slates your roof can accommodate.

As PV Slate is an electrical product, there needs to be a border of two natural slates around the edges of the roof and any roof windows.  We can make passive "infill" PV Slates to complete the surround for a perfect finish and a roof that no one would believe was solar.

GB-Sol has been at the forefront of solar panel and mounting system design for nearly 30 years.

We are proactive in reviewing our designs and ensure a culture of continuous improvement in methods, materials and testing. Global solar and construction accreditation bodies are used to test and certify our solar panels and mounting systems.

In independent fire tests, GB-Sol’s PV Slates achieved EXT.S.AA, the highest possible rating under BS 476-3: 2004 - Roof Fire Test. Testing also confirmed passes for the CEN/TS1187:2012 Test4. AA (national class) is equivalent to Broof(t4) (European class), the highest class and the only classification allowed to span full roofs and the compartmentation of buildings.

The carbon payback of a PV Slate unit is estimated to be 5.2 years, based on the UK grid carbon intensity in 2022.  PV Slates have a 25 year warranty on both solar performance and waterproofing.

An independent study (compliant with PAS 2050;2011) estimated that a single PV Slate unit had a carbon footprint of 19.38kgCO2e.

Each unit has a rated output of 28W and is expected to produce in excess of 500kWh over its 25 year warranty period, assuming it is not shaded or north facing.  That gives a PV Slate carbon footprint per unit of output of 39gCO2e per kWh.

The UK electricity grid mix in 2022, the lowest carbon year ever excluding Covid in 2020, had a carbon intensity of 182gCO2e per kWh.

On that basis, the carbon footprint of PV Slate would be paid back in the first 106kWh of its solar output, which would be generated in less than 5.2 years of its warrantied 25 year life.

The system has a total thickness of 80mm above the battens, which is about the same as clay tiles, but will stand slightly above slates.

The roof needs to have at least a 10 degree pitch to ensure the drainage system is sufficient in removing any condensation from behind the panels.  If less than this, then you will need a single ply, steel sheet or similarly waterproof roof surface for us to fix over.  

The maximum roof pitch for standard installations is 45 degrees.  Steeper pitches require additional considerations depending on the size and location of the roof, so please contact us to discuss your project in further detail.

Yes, contact us to discuss why this may be important for your project.

20kg per square metre, so much lighter than most clay tiles & slates

GB-Sol has been at the forefront of solar panel and mounting system design for nearly 30 years.

We are proactive in reviewing our designs and ensure a culture of continuous improvement in methods, materials and testing.  Global solar and construction accreditation bodies are used to test and certify our solar panels and mounting systems.

In independent fire tests, GB-Sol’s Infinity and Integrated solar roofs achieved EXT.S.AA, the highest possible rating under BS 476-3: 2004 - Roof Fire Test.  Testing also confirmed passes for the CEN/TS1187:2012 Test4.  AA (national class) is equivalent to Broof(t4) (European class), the highest class and the only classification allowed to span full roofs and the compartmentation of buildings.

Yes.  GB-Sol is the only manufacturer of conventional solar panels in the UK and we have been manufacturing solar panels in South Wales since 1994.  Romag & Sharp were other notable solar panel factories in the UK, but their manufacturing operations are now sadly closed.

GB-Sol is the only solar panel manufacturer on the Made in Britain website:

https://www.madeinbritain.org/members/gb-sol-ltd

As for other companies you might across in a web search for UK solar panel manufacturers, the following call themselves manufacturers but don't claim to have any factories or production assets:

Viridian (now owned by and marketed by Marley) - yes, they are a British company and they have their own designs, but their products are all sub-contract manufactured in the Far East.

UKSOL - with a name flatteringly like our own, their website claims "The British Solar PV Module Producer", but the small print says that their panels are sub-contract manufactured in the EU.  UKSOL then add their 30 year British warranty, but the company value is sub-zero according to their latest accounts.

It really depends on the roof area available and the household's power need. Most domestic PV systems are between 2-4kWp. 4kWp is the largest possible without requiring consent from your electricity distributor.

Provided the panels are at an angle greater than 15 degrees, they are self cleaning and require no additional maintenance other than a standard annual electrical check.  For our comprehensive weatherproofing warranty available on PV Slate and the Roof Integrated System, systems must be inspected and serviced every five years.

Our lead times can vary greatly depending on our current order book. For a domestic system, it’s usually between 4 and 8 weeks. We can give you an estimated lead time on request though this will be subject to change until we receive your order.

No, although a South facing roof will generate the most energy, East and West facing roofs can also be suitable for solar. In fact as they often generate more in the morning and evening, they can work out more cost effective if your home is empty during the day.

For a system under 4kWp you do not need permission to install, but if connecting to the grid, they should be informed of the installation and commissioning.

GB-Sol solar PV systems are designed to be non-earthed, but we do earth systems where metal parts can be reached from the ground or from windows, as systems carry a static charge during operation.

Battery storage complements solar PV systems by storing excess energy generated during the day for use during the evening and night. This reduces reliance on the grid and helps save on electricity costs.

Battery storage systems capture surplus solar electricity during the day and store it for later use. They can also provide backup power during outages, increasing property independence.

Batteries have historically been costly, but prices are decreasing as technology advances and market demand grows. They are an investment in long-term energy savings and independence.

Battery performance depends on various factors, including property energy needs, solar PV system output, and future energy market changes such as electric car charging.

GB-Sol solar PV systems are compatible with all makes and types of battery storage systems. Batteries monitor the main electricity meter to detect surplus power or grid imports, ensuring seamless integration.

Battery storage is part of the evolving energy landscape, offering benefits like reduced grid reliance and potential savings. Consider your energy needs, future plans (e.g., electric car charging), and budget before investing in battery storage.