Rubble masonry can be made from both rough, un-dressed hides or hewn, well proportioned blocks. Depending on the type of stone the block themselves can be very large, however it is also possible to find smaller stones. Regardless of size, the stones are always set in mortar, the joints of which can vary in size from very broad to very narrow.
Natural stone facades may already be strongly weathered, cracked and/or torn, if this is the case then they must be plastered before any drilling can be done, making them plaster masonry, please click the link for more information. Always be aware of the durability of the stones, before installing a climbing aid system.
Protruding aspects of the wall such as cantilevers, cornices, etc. can be made of soft, natural stone like sandstone, which is relatively weak. Therefor we recommend that you only attempt to attach a trellis fitting if the facade is thick enough and err on the side of caution by using a low pressure installation method, i.e. bonding with composite mortar as opposed to rawlplugs.
With the excessive unevenness of rubble masonry walls, we recommend that you use wall anchors with an extra long, protruding shaft to allow you to create the desired distance away from the wall. You may find it necessary to use more anchors than initially planned in order to find a sufficient, secure fastening spots.
All 5 FassadenGrün construction styles, with their standard wall anchors, are compatible with this material and can be fastened in the stones or in the joints - you may find you that you have to drill into both, in order to successfully install your selected trellis. If attaching in narrow stone facades such as cornices or cantilevers, avoid any kind of expansion anchor as they exert too much pressure on the rock and will do too much damage. Use an expansion free anchor or rawlplug and secure with composite mortar. Hammer drills, universal drills, and percussion drills are all equally suitable.