Repairs to the cardboard roof – Bitumen makes holes tight again

Professionally installed cardboard roofs can last a long time. Provided they are taken care of, and damage is repaired immediately.
Big heat, freezing cold, snow load, Sturm, Rain and falling branches clog house roofs. Nevertheless, inexpensive cardboard covers often last for decades. Regular inspections contribute to this, collecting fallen branches or removing foreign bodies and repairing minor damage. A lot of rubbish accumulates in a short time, especially on slightly sloping roofs. Announces even a damage by cracks, bubbles or displacements of the webs, must be acted upon immediately. Does water first penetrate the wooden structure or is it already dripping into the rooms below, the resulting damage is unforeseeable. When inspecting, great attention must also be paid to all seals at connection joints.

Partially renew cardboard
It is advisable in stressed areas, not to be repaired, but to reassign parts. This can be done with new sheets of cardboard or with cardboard shingles, that are easier to handle. Announce several damages over a larger area, the whole roof should be covered with a new layer of cardboard.

seal joints
Due to the high temperature differences, that occur on roofs due to the weather, connection joints are particularly stressed. This applies to connections to other components as well as between materials with different expansion values. Where roofing felt against masonry, metal bezels, plastic parts or mortar joints, utmost attention is required. Finest, Barely visible hairline joints allow moisture to penetrate, which can then carry out its destructive work in secret. With a special sealing compound based on bitumen, which are available in cartridges and also in larger containers, can be easily remedied.

eliminate bubbles
Bubbles can form in roof sealing sheets for various reasons. The blisters can be circular or elongated like veins. As long as the stretchability of the material is sufficient, nothing happens yet. Does the material become brittle due to the cold or are there additional mechanical loads from branches or walking on it, the bubble collapses and the roof leaks. For this reason alone, cardboard roofs should be walked on if possible.