Gutter expander from GRÖMO – Always in motion.

No tension here, guaranteed.

All materials against and on the roof are exposed to especially severe temperature fluctuations. It is not uncommon for the change between hot and cold to be volatile. During storms, for example, it can grow colder by a couple degrees within a few minutes. But in the early part of the year, it also often occurs that bright sunshine by day turns into frost in the night. In addition to that are also different regional factors like sun exposure and shadows, which also change the expansion behavior of the individual components. In order to head off material stretching and prevent tension in metal, expanders, also known as expansion compensators, are installed in roof gutters. Without dilatation elements, temperature fluctuations can severely damage the gutter or the gutter corner, leading to high costs. Soldered seams and adhesions of bitumen sealing membranes are especially threatened by this stretching of the material. GRÖMO motion compensators can be installed into any given profile by soldering or welding in, without a problem.

Please keep distance.

When it comes to determining the optimum distance between two expanders in a gutter, there are different aspects to keep in mind. First, it depends on what type of roof gutter it is. Is it a suspended or an inboard roof gutter? Then it’s important to know if the cut is under or above 500 mm. Depending on the type and material design, the required distances between the individual gutter expanders can be between 6 m and 15 m.
 

Gutter expander installation instructions

While installing motion compensators, make sure that the sheet metal in front of the rubber as well as the rubber middle part are covered with a wet towel so that no heat can transfer to the rubber middle part. You should maintain a minimum distance of 6 cm to the middle part of the rubber. It should never come into contact with open flame.
 

What to pay attention to when laying tape and head expanders:

The bending bar should have a minimum radius of 2 mm when beveling and installing. In addition, a bending radius of 5 mm must be attained for sheet metal that is 1 mm or thicker. The folding beam should be lowered 3-4 mm according to the thickness of the rubber middle part, to avoid being sheared. It’s important that the rubber middle part not be crushed or damaged. Therefore an aluminum metal strip, 205 mm thick, should be trimmed so that it can be put on the folding beam like a shoe. This will give you a bigger bending radius and prevent the rubber middle part from being harmed. Optionally, you can also use a bending machine with segments.