Several factors can influence the number of ground screws you may require for a project.
Some primary considerations are listed below, but if you would like any assistance planning for your project, get in touch with our team, and we’ll be happy to help.
What type of structure are you supporting.
You will require more ground screws to support a heavy timber frame building, such as a garden office, than a decking area of a similar size. Loads are transferred through the structure to the foundations, with loads being distributed evenly across the number of ground screws installed.
What size of sub-frame you are installing.
It is also essential to consider the main support structure installed on your foundations to avoid deflection between fixed points. Ground screws are typically installed in a grid pattern to support the frame sitting on top. For example, an 8″ x 2″ timber will span a greater distance than a 4″ x 2″ timber. Therefore, ground screws may be installed closer together on a lighter frame to avoid excessive deflection between fixed points.
What the ground conditions and soil types are.
These can vary significantly and may determine how many ground screws are required. If ground conditions are determined to be less favourable, offering less than the average load-bearing capacities, you may need a greater number of ground screws to spread the load. Alternatively, we may install longer ground screws to reach better, load-bearing ground.
Contents and additional heavy loads.
You may be getting a hot tub installed or using your space as a home gym. If you have specific areas where loads may be greater than others, we would advise additional ground screws at those locations. Additional screws will allow for the extra weight to be transferred through your foundation and adequately support your sub-frame to avoid deflection.
To give an insight into the number of screws you might need, below is an example project for a 4m x 3m garden room with extended decking area.
Our team is always on hand to advise and assist with your project. If you require any help, please do not hesitate to get in touch, and we’ll be happy to support you!
You can also use our online Ground Screw Calculator as a quick guide, but please remember it’s not a one size fits all, and we are always available to provide professional advice.
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