Cardboard dock

Cardboard docks were used by roofers, especially in northern Germany, as an additional measure to prevent drift snow, fly ash, etc. from penetrating under the roofing before roofing membranes were used for this purpose.

Dock originally consisted of straw. They were later replaced by cardboard docks cut from sheets of roofing felt. A side effect of using the bitumen sheeting was a certain amount of gluing of the entire roof covering and thus additional wind suction protection.

In other regions, beaver tail covers were sealed with wooden spikes . Other forms of brick were mortared. In the middle and high mountains, massive sub-roofs made of boards were built in combination with a layer of roofing felt.

Cardboard docks were matched to the roof tile or roof stone mass and usually 2 roof tiles or roof tiles plus about 10 cm long. The width corresponded to the width of the roof tiles plus around 10 cm. They were laid on the previous row of roof tiles with cover and the next roof batten. The roof tiles / stones followed immediately afterwards. Then the protruding end of the dock was wrapped around the heads of the roof tiles, the next dock followed, etc. In this way, an overlapping sub-roof was achieved under the roofing.

Cardboard docks no longer correspond to the recognized state of the art.

1. They prevent adequate ventilation of the roof structure. In addition, the insulation of the roofs used today prevents the inside of the roof from heating up, and thus the underside of the roof covering. As a result, condensate can no longer dry off, which can lead to damage to the roof tiles in the long term.

2. When using cardboard docks, the side seam clamps commonly used today for securing roofing against wind suction cannot be used. With the only usable head clamps, today's requirements for storm security of roof coverings are usually not met.

3. To keep the cardboard docks as pliable as possible and to prevent them from breaking during the covering, a relatively high bitumen and solvent content was necessary. This is detrimental when a fire breaks out.

Nevertheless, cardboard docks are still available in northern Germany and are still processed there today. The roofing company carrying out the work must obtain object-related approval from the roof tile / stone manufacturer in order not to lose the guarantee claims.