How to Prepare Your Site for a Prefab Shed

What Can I Do Before My Shed Arrives?

Before starting to prepare your site for a project, become familiar with your assembly manual and determine if you can complete the project yourself or will require a professional contractor. Please note that certain counties and municipalities require building permits prior to installation. We recommend to all consumers that they check with their local county/municipality for these specifics prior to purchasing any product since this is your sole responsibility. Prior to the product arriving, clear the construction area. Remove all debris; roots, grass, rocks, etc.
Make sure the ground slopes away from the site at least 10 feet in all directions. If necessary, build up the soil in the center of the site and slope away for the high point to provide drainage. Fill in any low spots within the perimeter of the site. A slope of 1/8 inch per foot is enough to prevent water accumulation. We recommend excavating the site 4-6 inches deep and laying gravel or crushed rock where drainage may be a concern.

What Type of Foundation Should I Use?

Patio Stone Foundation:

If the ground is stable and has sufficient drainage, you can set patio stones directly on firm compacted soil. If not, consider laying down sand and then gravel or crushed rock. Excavate the site making it about 12” wider and longer than the floor footprint. Excavate down approximately 4-6 inches deep. Lay 1-2 inches of sand first and then fill with 3-4 inches of gravel or rock for good drainage and support. Most sheds and playhouses include floors with support runners. Support each runner with 4-5 patio stones (less for smaller sheds). Patio stones can be anything from a mid size brick to a round our square 12” long by 1 1/2” thick stone. Place stones directly under the floor runners, check for level and adjust height as necessary. Having a solid and level foundation is the most critical piece of work you can do to make the project go smoothly. Most of this work can be done prior to your shed arriving!

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4×4 Pressure Treated Beam Foundation:

You can build directly on pressure-treated beams or railroad ties laid on a properly prepared construction site as mentioned above. Run beams perpendicular to floor runners. Use a 2×4 straight piece of lumber on edge and a carpenter’s level to position correctly. To prevent the beams from shifting, secure them with ½ inch rebar inserted through holes drilled in the beams and driven 3 to 4 feet into the ground. Leave each side or end of the foundation open to promote drainage and air circulation beneath the floor. Consider using a wire mesh or equivalent to prevent pesky critters from gaining access on ends.

Concrete – Slab Foundation:

Typically a concrete slab 3-4 inches thick laid over a sub-base of 4 inches of gravel or crushed rock is sufficient but may vary depending on your geographic location. Using either mix your own concrete or having it delivered by truck, ready to pour, depends on how much time and effort you have to dedicate to the project. In any event, make sure you excavate the slab area to a depth 6 inches. This would put the finished slab surface approximately 2 inches above ground (remember you will be using 4 inches of gravel as your subbase).

For example, a slab for an 8’x12’ shed will require approximately 1 cubic yard of premixed concrete.

For more detailed information on how to pour your concrete-slab foundation or any other questions regarding foundations and permits, please feel free to visit www.outdoorlivingtoday.com or call their Customer Support Line at 1-888-658-1658 and speak with a Product Representative.