Use filling materials that do not absorb moisture
A1 is excellent to use in combination with a large number of filling materials. It adheres excellently to, for example, wood, textiles and chicken wire. Is it possible to add almost all small ground materials to the A1 mixtures, creating special shapes in appearance and structure.
For A1 objects that are placed outside, carefully consider beforehand whether this combination of materials also works well here. For example, we know that wood attracts moisture via the A1 and can even expand, causing the A1 layer to crack. Chicken wire will start to rust due to the moisture present in the A1 and this creates traces of rust in the A1. We encountered A1 objects where hydro grains were mixed in the A1 because it gave a nice structure. Subsequently, these hydro grains absorbed so much moisture that the surrounding A1 became soft and the top layer A1 with hydro grains subsequently separated from the underlying glass fabric reinforced A1 layers.
Only use filling materials that do not absorb moisture or that will corrode due to the moisture present. We have had good experiences with materials that do not absorb moisture and rust, such as granite, sand, EPS (styrofoam) and aluminum.
Reinforcement materials and inserts required for mounting can cause problems in outdoor situations when these materials absorb moisture such as wood. Then use aluminum, stainless steel, EPS or pre-produced reinforcement profiles or backs of A1.