FAQ

FAQs

General points

What are Solrif® solar tiles?

With the Solrif® system, unframed standard photovoltaic modules become solar roof tiles, replacing normal roofing. Solrif® makes it possible to install a photovoltaic roof system that is completely integrated with the building.



Do PV Modules with Solrif® meet the requirements for “hard roofing” (resistance against flying sparks and radiating heat)?

Module manufacturers have their BIPV products tested by authorized institutes to guarantee that they fulfil the requirements for "hard roofing". Modules with Solrif® have passed these tests. Certificates can be obtained directly from the different module manufacturers.



What is Solrif®?

With the Solrif® system, unframed standard photovoltaic modules become solar roof tiles, replacing normal roofing. Solrif makes it possible to install a photovoltaic roof system that is completely integrated into the building.



What are the fundamental features that make Solrif® special?

Solrif® is highly flexible. As a result, PV modules measuring up to 1.0 m x 1.75 m and with a thickness of 5.2 mm at the periphery can be used. There are a number of PV module manufacturers who offer their products along with the Solrif® system through the normal trade channels.
By contrast with other mounting systems, with Solrif® the photovoltaic modules are not clamped or wedged in place but laid. Each module is fastened with a single fixed point and one or more sliding points. Furthermore, for servicing purposes the modules can be individually removed in situ. The free lower glass edge allows snow to slip off and accentuates the self-cleaning function of the modules. This has a positive effect on the yield.
Solrif®’s extremely slim frame profile maximises the area of roof that can be laid with active PV modules.



Is Solrif® certified?

Solrif® as a system cannot be certified without the module. However, the manufacturers of PV modules with a Solrif® frame can at least obtain extended certification over and above the basic certificate, based on mechanical load testing to IEC standards.



Do in-roof systems have a lower yield than on-roof solutions?

Depending on the installation specifics and the pitch of the roof, the yield may be up to 5 % less, but in view of the free lower edge and self cleaning properties the annual yield may actually be better.



Is Solrif® suitable for façades?

Considering the very different requirements for façades (in terms of statics, hazards and fire protection), this kind of use is not covered. Whether or not it is feasible must be scrutinised by the user in the individual case.



Sales

Where can the system be obtained?

Various manufacturers and dealers offer in-roof systems on the basis of Solrif®.



Do you have any references, and where can I find them?

Numerous reference buildings can be found on this website.



What guarantees are offered for the system?

On request we can offer a guarantee period of 10 years, based on written agreement. In other respects relations with the customer are subject to the terms and conditions of business of Ernst Schweizer AG, as well as the Swiss Law of Obligations.



Do you offer dummy modules?

Schweizer and it’s partners provide dummy modules. The cheapest and quickest solution is to procure the standard dummy modules from our trading partners, and adjust them to the required dimensions on the roof.



Are hybrid modules a possibility?

In principle this would be possible. Currently, however, no manufacturers are known to us who offer their hybrid modules with the Solrif® system.



Do you offer a bill of specifications or tender texts?

Tender texts are available on request from solar@ernstschweizer.ch.



Technology

What kind of maintenance do Solrif® systems need?

We recommend that an inspection be carried out by a roofing specialist every two or three years.



What does the system weigh?

The weight of the system consists in the weight of the module plus ca. 2.5 kg per frame roughly 11 kg/m2.



Can Solrif® be installed with a 10 ° roof pitch?

It is technically possible to install the system on a 10 ° sloping roof. The wind load (above all in the peripheral areas) should however be taken into account, and the self-cleaning function will be less effective. There is also a risk that the modules may be forced out of the mounting bracket.
When the pitch is below 22 °, additional measures such as sealed underroof with effective drainage are necessary.



How effectively sealed is Solrif® (waterproof, rain-proof)?

European Norm prEN15601 specifies a standard roof pitch of 22 °. Within the prescribed limits of use (10 to 70 °) the relevant roofing guidelines (e.g. SIA 232/1 for Switzerland and ZVDH for Germany) must be followed.



What material is used to make the Solrif® frame?

The Solrif® profile frame and the peripheral connecting profiles are aluminium extruded profiles with a highly weather resistant powder coating. The support and sealing profile is made of the synthetic rubber EPDM. A 1-K silicon adhesive is used for the framing and sealing. The mounting brackets are stainless steel.



Can there be problems when the builder has used copper sheet flashing?

Aluminium and copper constitute an electrochemical element, as a result of which the aluminium is likely to corrode. This is not a problem, however, if steps are taken to ensure that no unpainted aluminium parts come into direct contact with the copper sheet. The paint ‘insulates’ the aluminium from the copper, so to speak.



How many parts / articles make up the Solrif® system?

The system consists of the framed module, the flashing or adapter profiles and the mounting brackets. For rectangular subsections of the tiled roof there are 7 types of connecting metal sheet and an eaves sealing system.
A cable set for equipotential bonding can also be supplied.



Building technology applications

In terms of building technology, can different module sizes be combined with one another?

Basically the answer is yes. But the modules in one row must have the same height, so that the sides overlap is in place to keep out the rain. The market already offers ‘module families’ of this kind.



Can I install Solrif® from the top down?

This is in principle possible, but it is more difficult and laborious, because the brackets need to be mounted accurately beforehand. The modules can then be inserted from below. The EPDM seal must remain in position while you are doing this.



What is the maximum permissible wind and snow load?

Planning needs to be based on the Eurocode and/or SIA 261. In relation to wind and snow load, diagrams are obtainable on request from solar@ernstschweizer.ch, showing the permissible limits of use.



What needs to be taken into account when you have a lot of snow?

When the Solrif® modules are supported with an additional roof batten for each row, greater accumulation of snow is no problem. These solutions need to be checked in the light of the specific project. A snow guard can moreover limit the downward impetus on the slope. Please check our tec-note.



How can a snow guard fixture be installed?

In the case of part roof solutions, the snow guard can be realised in a perfectly conventional way in the lowest rows of tiles. With whole roof solutions, the snow guard can be installed on a row of dummy modules having a minimum height of 370 mm. The measurements of the snow guards must be adjusted to the specific building.



When are several snow guards necessary?

On high elevation locations, an additional snow guard should be installed every 4 m, or after every three or four rows of modules. Please consult Schweizer’s tec-note on this topic, obtainable on our website.



How should the underroof be designed?

Underroofs should be designed in accordance with the applicable building standards (SIA 232/1 for Switzerland, ZVDH for Germany). A factor to bear in mind is the higher temperature (up to 80 ° C) to which the roofing membranes will be exposed. So suitably resistant products need to be used.



What sizes of skylight are obtainable?

Skylights are obtainable in module width and in single or double module height.



I have a hipped roof. How can I cover the entire roof with Solrif®?

On hipped roofs it is possible to create an approximate photovoltaic field by arranging the modules as a trapezoid. The areas left clear will be laid with dummy modules which have been cut to the size and shape required.



Electrotechnical applications

How does equipotential bonding work?

Each Solrif® module has two drill holes for equipotential bonding on the upper frame. With an grounding cable, all the modules can be joined together. Special earthing sets are available for this.



Does a Solrif® photovoltaic system need to be connected to the lightning protection system?

Where a lightning protection system already exists, either the PV system needs to be connected with it or the prescribed safety distances have to be respected. NB: Installation of a photovoltaic system does not entail any lightning protection obligation. If you require further information, please ask a qualified lightning protection expert.