Fastening types

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Mechanical fastening
Glued fastening
Fastening distances

Regardless of the panel size, at least 2 fixed points are required for the mechanical fastening of each panel. This is the only way to ensure that the panel is positioned stably and cannot twist.

Always use T-profiles with a support surface of at least 100 to 120 mm for the panel joint. L-profiles with a support surface of 40 mm are sufficientbetween the joints.

In order to take the expansion of the material into account, supporting rails must not be longer than 3,000 mm. Ensure that the substructure profiles are not joined in one panel, since a fixed connection is created here.

2 fixed points positioned in the centre.
There is room for expansion upwards and downwards.

2 fixed points positioned in the centre (on the support profile).
There is room for expansion all around.

On larger panels installed on several vertical support panels, we recommend positioning the panel with 3 fixed points in an L-shaped arrangement in the centre of the panel.
If required for static reasons, 4 fixed points in a rectangular arrangement are also possible for large panels.

The riveted mechanical fastening system consists of a façade rivet and, if desired, a fixed point bushing.

In order to achieve centric drilling of the substructure, only use either the appropriate bracket boring fixture or the spring-loaded boring fixture, which transfers the centre of the bore hole of a composite panel to the substructure.

Bracket boring fixture for metal supporting substrates

Spring-loaded boring fixture

x = drilling of the supporting sub-structure y = drilling of the panel

Mechanical fastening

Use the PREFA film cutter (⌀ 5.1 mm and ⌀ 9.5 mm) to slightly score the protective film around the bore hole so that the protective film can be easily removed after the installation is complete. Otherwise, the film may become clamped between the panel and the bottom of the rivet head, making it difficult to remove.

Film cutter

Note

When riveting, regardless of whether it is a fixed or sliding point, always use the appropriate rivet nosepiece to prevent surface deformation and to ensure the panel can move (material expansion).

Rivet nosepiece

The rivet nosepiece is screwed onto a standard rivet gun (or riveting device) with threaded connection M10×1 mm.

1 Rivet nosepiece

2 Rivet fastener

In this case, the panel cannot expand because the PREFABOND aluminum composite panel is firmly connected to the rails at this point.
To do this, the panels are pre-drilled using a ⌀ 5.1 mm or ⌀ 9.5 mm drill bit.

For a hole size of ⌀ 9.5 mm, the bore hole must be filled with a fixed point bushing of ⌀ 9.5 to ⌀ 5.1 mm.
For a hole size of ⌀ 5.1 mm, no fixed point bushing is required.

The metal rail is always pre-drilled with a hole size of ⌀ 5.1 mm.

Fixed point on metal supporting substrate (hole size: ⌀ 9.5 mm; with fixed point bushing)

1 fixed point bushing

Fixed point on metal sub-structure framework (hole size: ⌀ 5.1 mm; without fixed point bushing)

The bore hole is larger than the diameter of the fastener. All fastening holes of the panel are pre-drilled using a ⌀ 9.5 mm drill bit. The metal rail is always pre-drilled with a hole size of ⌀ 5.1 mm. This is the only way for a sliding point to be able to absorb the thermal material expansion of the panel.

Sliding point on metal supporting substrate

The screwed mechanical fastening system consists of a facade screw, a special LT-XT TOOL TX 25 bit and matching fixed and sliding point bushings.

Fastening material for metal rails/profiles screwed

In order to achieve centric drilling of the substructure, only use the centring bushing for fixed and sliding points that is matched to the fastening system.

All fastening holes, regardless of whether they are fixed or sliding points, are only pre-drilled with a hole size of ⌀ 11 mm (Fig. 1).
Insert the fixed point bushing, which reduces the bore hole from ⌀ 11 to ⌀ 5.8 mm, holds the panel in a firmly defined position and prevents further movement (Fig. 2).

Then rotate the fixed point bushing a few turns with the LT-XT tool so that the protective film is cut (Fig. 3).
The fixed point bushing has a small ridge on the back, which cuts into the film (Fig. 4).
Then place the fastening screw in the centre of the fixed point bushing and screw it in centrally (Fig. 5).

Insert the sliding point bushing, which reduces the bore hole from ⌀ 11 to ⌀ 8.4 mm and subsequently absorbs the expansion of the panel. Similar to the fixed point bushing, rotate the sliding point bushing a few turns so that the protective film is cut (Fig. 6).
Then place the fastening screw in the centre of the sliding point bushing and screw it in centrally (Fig. 7).
Due to the small ridge on the back of the fixed and sliding point bushing, the film can be easily removed from the PREFABOND aluminium composite panel in the final step (Fig. 8).

In order to achieve centric drilling of the substructure, only use the appropriate bracket boring fixture which transfers the centre of the bore hole of a composite panel to the wooden substructure.

Bracket boring fixture for timber supporting substrates

Mechanical fastening

Use the PREFA ⌀ 9.5 mm film cutter to slightly score the protective film around the bore hole so that the protective film can be easily removed after the installation is complete. Otherwise, the film may become clamped between the panel and the bottom of the screw head, making it difficult to remove.

Film cutter

The hole size of the fastening points is always ⌀ 9.5 mm, regardless of whether it is a fixed or sliding point. The timber sub-structure framework is pre-drilled ⌀ 9.5 mm to ⌀ 3.3 mm using the bracket boring fixture for timber sub-structure frameworks in order to enable the screw to enter at right angles and centrically and to prevent the square timber from breaking out. Then press the façade-centring joint into each bore hole, regardless of whether it is a fixed or sliding point.

Note

In order to protect the wooden substructure from water penetrating it, it is important to apply a EPDM sealing tape to all vertical support profiles. This must protrude over the square timber by at least 5 to 10 mm on each side.

Since the PREFABOND aluminum composite panel is firmly connected to the wooden substructure at this point, a fixed point prevents the panel from moving. To obtain a fixed point, press the fixed point bushing ⌀ 8.5 mm to ⌀ 5.1 mm into the bore hole. In the next step, the screw can be screwed in.

Fixed point on timber supporting substrate

1 Façade-centring joint
2 fixed point bushing
3 EPDM sealing tape

4 PREFABOND
5 Façade screw
6 Timber sub-structure framework

Note

Tighten the screw with a moderate torque so that the screw holds the panel sufficiently in its position, but without pushing out the façade-centring joint from under the screw head.

For mechanical fastening to a wooden substructure, the sliding point is designed in the same way as the fixed point. The only difference is that no bushing is inserted into the façade-centring joint.

Sliding point on timber supporting substrate

1 Façade-centring joint
2 EPDM sealing tape
3 PREFABOND

4 Façade screw
5 Timber sub-structure framework

Adhesive system (PREFABOND)

1 Adhesive (beading)
2 Double-sided adhesive tape

3 PREFABOND
4 Metal sub-structure framework

The following points must be taken into account for the supporting substrate:

Only use smooth profiles, as it is not easy to remove grease from grooved support profiles.
Ensure that the substructure support profiles are only uncoated in order to be able to guarantee optimal adhesion.)
Only carry out the bonding vertically.
The sub-structure framework distances must not be larger than 500 mm.
If larger panels and other supporting substrate distances are to be used, it is essential to consult the adhesive manufacturer beforehand.
Bonding to a timber sub-structure framework requires increased care and may only be carried out in direct consultation with the adhesive system manufacturer.

The following points must be taken into account for the adhesive system:

Observe the manufacturer's specifications concerning temperature and humidity.
Keep a bonding record as required by the adhesive manufacturer.
Observe the product’s expiry date.
Make sure that the minimum thickness of the beading and the double-sided adhesive tape is respected.
Adhere to the specified flash-off and drying times.
Observe the safety data sheet specifications regarding personal protective equipment.

The following points must be taken into account for the PREFABOND aluminium composite panel:

The panels should be pre-treated according to the adhesive manufacturer’s application guidelines (priming, roughening, degreasing, etc.).
The maximum panel format must be observed in accordance with the application guidelines and the approval of the adhesive manufacturer.
The composite panels must be installed according to the fire protection concept.
The bonding of soffits requires particular care and should be planned in coordination with the adhesive manufacturer. In case of doubt, additional mechanical protection should be provided for the cladding.

The horizontal spacing [X] between the vertical support profiles depends on the static requirements. Individual, building-related planning is essential.

Fastening distances

Y … (along the support profile) = max. 500 mm
X … center-to-center spacing of support profiles (mechanical fastening) = max. 800 mm
X … center-to-center spacing of support profiles (bonded fastening) = according to the adhesive manufacturer’s specifications

PREFA recommends that the sub-structure framework distances should not exceed 800 mm for mechanical fastenings. For bonded fastening, the sub-structure framework distances must be observed according to the adhesive manufacturer’s specifications. Otherwise, depending on the colour, gloss level and how the light falls, the surface may take on a wave-like appearance.

ra (distance to edge) ....... 25-50 mm

PREFABOND aluminium composite panels can be fastened either mechanically or abonded to soffits. Spacing of rails in a grid of 500 × 500 mm should not be exceeded.

Note

If the selected distance is too large, a crowning of the panel may become apparent, depending on the colour, gloss level and how the light falls.

Fastening types

Mechanical fastening

Arranging the fixed and sliding points

Riveted onto a metal bracket and rail system

Screwed onto a metal bracket and rail system

Screwed onto timber sub-structure framework

Glued fastening

Supporting substrate

Adhesive system

Composite panel

Fastening distances