Roof system PREFALZ

In the case of standing seam coverings, pre-profiled or folded panels are folded together to create a rainproof joint. The angled standing seam is primarily used for façades, while the double standing seam is used on roof surfaces. The following two images show the cross-sections of double and angled standing seams:

PREFALZ offers a wide range of standard colours, mainly in P.10 quality, with a 40-year colour guarantee. The paint coating is applied and fired in several processing stages in the coil-coating process. As a result, the coating layer is malleable and very weather-resistant.

Notes

• The RAL values stated are merely approximate values (~), some of which may differ vastly from the original PREFA colour and, under certain circumstances, may not reflect the subjective perception of the colour.
• Above all for colour quality P.10, it is almost impossible to define values due to the surface structure. In addition, the PREFA Siding colours P.10 stone grey, P.10 sand brown, P.10 Prefa bronze, P.10 patina green, natural oak, patina grey, walnut and grey oak are based on natural colours made up of several different shades.
• Coils and metal sheets plain aluminium: The guarantee does not cover surface appearance alterations caused by processing and environmental influences. Follow the instructions.
• Metallic colours may vary in shade.
• To identify exact colours for complementary components please consult original samples.

The standing seam technique is the classic application type for metal roofs. With this technique, the building’s entire shell, i.e. roof and façade, can be clad to create an image as if from a single mould. The technique enables major creative freedom with uniform or varying panel widths as well as conical panels, in addition to the wide range of colours.

PREFALZ is also used for all details such as mantelpieces, wall coverings, verges and much more in PREFA small-format roofs.

We have summarised more Tips for choosing the right roof covering for you here. You will find even more inspiration in the Reference Gallery or Renovation Gallery.

Caution: Mixing PREFALZ coils with colour-coated aluminium from competitive manufacturers, but also with FALZONAL® material of supposedly the same colour, should be avoided at all costs because of the different paint qualities and subsequent differences in weathering. Only in this way can you enjoy a harmonious-looking façade even after many years. This must also be observed for weatherings, cappings and the like.

PREFA aluminium roofs are produced with a ventilated substructure, with the roof cover and thermal insulation layer separated by a ventilated gap. This means any occasional condensation can be wicked away.

It is mostly the roof membrane that is ventilated, as shown in the first picture. However, the whole attic space can also be ventilated (second picture). 

Separating layers arranged directly under the roof covering can fulfil a variety of tasks. Whether a separating layer is used or which separating layer is to be used should thus be already taken into account in the planning phase.

Separating layers can:

• protect the wooden formwork or wood-based panels from moisture during the construction phase.
• improve sound insulation (acoustic decoupling).
• compensate for minor unevenness in the roof structure.
• improve the extension and contraction of the trays.
• protect the metal on the underside against damaging alkaline influences and possible harmful chemicals in substrate.
• support the roof covering and the sub-roof with regard to the rainproof function.

Depending on the function that a separating layer is to assume, a suitable product must be agreed with the manufacturer of the separating layers. If, for example, the separating layer’s function is to provide additional sound insulation, the use of stronger, heavier bitumen separating layers (e.g. BauderTOP UDS 3 NK or similar) is recommended. If the separating layer is “only” intended to protect the substructure during the building phase, a thinner bitumen separating layer can be used (e.g. BauderTOP TS 40 NSK or similar).

The length of the fixed area is 1–3 metres depending on the panel length. Positioning of the fixed clips area must always be selected in relation to the existing roof pitch (see fig. and associated table) Penetrations or the roof shape may affect the position of the fixed clips area. Elevations with variable fixed clip areas must be separated by separating strips.

Here, our installers and architects can download specification documents and details about PREFALZ. In the service area, you will find the info sheet about the mantelpiece with PREFALZ, installation guidelines for the walkway support for PREFALZ, installation instructions for Vario solar bracket with PREFALZ as well as PREFALZ installation videos. For more information on the installation, see the PREFALZ installation guidelines. The service area is only accessible for partner companies – please have your log-in details ready. Not received your log-in details yet? Please contact your Local Sales Manager in that case.

Special note for our architecture and design studios: 3D and BIM data, as well as textures for our products can also be found here: digital planning

Here you can find more about the specifications on our NBS platform.

Clips with stainless steel nails, screws or rivets are to be used to fasten standing seam applications. In order to ensure a sufficient snow guard system, seam clamps including snow guard pipes and ice stoppers are used for standing seam coverings. These system accessories and others, such as the PREFA sealing gel, include PREFA’s complete system.

For a complete, detailed list of accessory products, see our price list (only for processors).