Van der Valk Solar Systems Blog

Solar Mounting Systems on Standing Seam Roofs

Standing seam roofs (also known as Kalzip and Zinc) has increased in popularity among architects due to its aesthetically pleasing look, robustness and weatherproof qualities. It is now more common to see on pitched roofs, especially in the educational and leisure sector. Seamed roofs are commonly made from Steel, Aluminium and Zinc; as seam roofs are made from metal, it can have a cooling effect due to its reflective coating which can reduce energy consumption up to 20%, which complements solar PV framing perfectly.

ValkPitched Clamp Standing seam - Imelda ZH (1)-1

There are a number of different roofing manufacturers specializing in standing seam along with different types, in simple terms, the seam type is classified as 'Straight' or ‘Round’ and is either single or double folded.

Mounting solar PV systems to a seam roof is relatively straight forward and fast, which reduces install time and decreases labour costs. The clamps are secured directly over the seam which is then fastened with a screw at the side, the rail then connects directly to the clamp using a hammerhead bolt and L-Adaptor. The benefit of using a seam clamp is that there is no need to penetrate the roof, therefore no risk of water leakage.

Which clamp to use and how many?

First, it’s important to check with the roofing manufacturer, in some cases they will have their own specific type of seam clamp to use for Solar PV mounting and using a third-party clamp may void the warranty. There are a variety of standing seam roofs on the market and new ones frequently being developed, specialist clamp manufacturers such as S-5! have a wide range of seam clamps that follow strictly to the roof panel rib to minimize distortion when tightening. Seam panels are secured to the purlins using a clip; this allows the panel to move over the clip freely as the temperature changes, therefore it’s important to find out the locations of each clip and be sure not to mount the clamps over them.

The Sheet thickness (ranges on average between 0.6 – 0.8mm) and the distance between the seam also plays an important factor when determining how many clamps are required within the array. Third-party strength calculations (normally conducted by the mounting kit company) based on wind uplift, snow load, sheet thickness etc. will be able to determine exactly how many clamps are required to secure the panels to the roof safely. Overall, although there are many types of seamed roofs, you have the peace of mind that there will be a clamp suitable for that particular seam.

How can Van der Valk Solar Systems help with your project?

Van der Valk solar Systems offer a clamp system suitable for both round and straight seams, which is available for horizontal/vertical mounting of side++ profiles for portrait and landscape orientation of PV panels. The clamps are made from aluminium and pre-assembled with a hammerhead bolt and lock nut thus enabling a faster install of the side++ profiles. Projects can be calculated using our online calculation tool, ValkPVplanner, which will generate a detailed report and full bill of materials required for your Solar PV design.

Valk Solar Systems can also offer technical support on specifying which clamps are needed, depending on the specific seam type when our own seam clamps are not suitable. The ValkPitched Clamp system is also suitable for special projects such as curved roofs and elevated systems, using our technical expertise, we provide strength calculations and full bill of materials for all your project needs. For further information and technical support, contact us today on +31 (0)174-25 49 99 or email to