Ground Screws in Rocky Ground
Installing foundations in rocky or heavily compacted ground can present challenges, particularly when using traditional methods that require extensive excavation. But can you use ground screws in rocky ground?
In many cases, ground screws can be a practical foundation solution for challenging ground conditions, although the suitability of a particular ground screw depends on the type and extent of the obstruction, soil conditions and requirements of the project.
At The Ground Screw Shop, our team can help you determine the most appropriate screw, length and installation method for your site.
Can Ground Screws Be Installed in Rocky Ground?
Ground screws are designed to be rotated into the ground rather than requiring large areas of excavation. However, particularly large rocks, bedrock and other substantial underground obstructions can prevent a screw from reaching its required installation depth.
This is why testing the ground before ordering your ground screws is important. The Ground Screw Shop recommends using methods such as an SDS drill with a masonry bit, a steel wrecking bar or a small trial dig to investigate ground conditions and identify potential obstructions.
If you encounter a small stone or localised obstruction during installation, a pilot hole may help you establish a starting point. However, you should never simply force a ground screw through a significant obstruction. If a screw will not install correctly or cannot maintain the required position, stop and assess the ground before continuing.
For particularly hard or difficult ground, mechanical installation may be more appropriate than manual installation. The Ground Screw Shop offers installation/machine hire for heavy ground conditions, longer screw lengths and larger installations.
The condition of the ground also affects the load-bearing performance of a ground screw. Published loading figures should be treated as indicative, as actual performance can vary depending on the ground conditions at your site.
Choosing the Right Ground Screw for Difficult Ground
When installing ground screws in rocky ground, choosing the correct product is only part of the process. The installation depth, position, ground conditions and required loading all need to be considered.
The Ground Screw Shop supplies a range of ground screw lengths, including 800mm, 1000mm and 1200mm options, allowing customers to select a suitable solution for different ground conditions and project requirements.
Longer screws can be useful where additional depth is required to reach more suitable ground, but simply choosing the longest screw available is not always the answer. The appropriate specification should be based on the actual conditions at your site and the loads your structure will place on the foundation.
Installation technique is also important. Ground screws should be kept as vertical as possible during installation, while their final height should be checked carefully. Regular use of a spirit or laser level can help ensure accurate installation. You should also avoid over-installing a screw and then winding it back up, as this can create a void beneath the helix and affect foundation performance.
For larger, heavier or more complex structures, professional advice is particularly important. With extensive experience across ground screw applications, The Ground Screw Shop can help you assess your requirements and select an appropriate foundation solution, whether you are working on decking, fencing, a garden room or another structure.
The Ground Screw Shop’s calculator is designed as a guide for lightweight garden structures, while heavier buildings and projects requiring Building Control approval should be discussed with its expert team.
Get Expert Advice on Ground Screws for Rocky Ground
If you’re dealing with rocky, stony or particularly hard ground, don’t assume that traditional concrete foundations are your only option. The Ground Screw Shop provides high-quality ground screws, installation equipment and expert support to help customers find a suitable foundation solution for their project.
Our team can advise on ground screw sizes, installation methods and the considerations involved when working with difficult ground. For projects where manual installation may be challenging, we can also provide information about suitable installation equipment and machine hire.
Before ordering, we recommend carrying out appropriate site testing so that potential obstructions and ground conditions can be identified. If you’re unsure which ground screws you need, our experts are available to help you through the process.
Contact The Ground Screw Shop today to discuss your project and find out whether ground screws are suitable for your ground conditions.