How to Install Skid Foundations
This is post 1 of 3 in our series “Rising Barn Foundations,” where our foundations are explained for installation.
Depending on the size and use of your new barn building, we will recommend that you use one of two foundation types: the pier system or the wall system. Each system has an above ground and a below ground solution that are discussed in this series. These are also popularly known as foundation skids, pier and beam, and spread footing, and footing wall systems.
The success of your building largely depends on how well your foundation is installed, no pun intended! If it is not installed correctly, then your home may shift, doors and windows may stick, and it may crack eventually. If it’s done correctly, however, a strongly founded house will stay dry, insulated, and sturdy for decades with little to no maintenance. Since the type of foundation is a crucial step that determines structural integrity of the entire barn, Rising Barn engineers will recommend the best foundation design suited for your structure.
Here is some insight on the thinking behind foundation design:
In the construction industry, the type of foundation is usually chosen based on A) the type of soil that you’re building on and B) how heavy the structure is. Many systems can meet both of these needs, so sometimes other needs influence the system selection. For example, sometimes hauling trailers serve well as foundations because they avoid zoning restrictions and allow mobility!
Above Ground Wall System, known as “Skids”
Stone blocks are first laid on sturdy troughs with stone gravel. Wood beams (the ‘skids’) are then placed on top of the blocks, and the sub-floor of the building is directly attached to the skids. We consider the skid system to be a type of above ground foundation because it functions a lot like a wall: bearing the load of the structure by dispersing it along a linear area, the trench.
Installation usually begins by digging a shallow trench to lay the gravel in. Usually the trench only has to be dug directly below the skids themselves, but some people like to dig out the entire area beneath their structure. Using gravel as a foundation may sound counter-intuitive at first, but it works. From railroad tracks to Frank Lloyd Wright homes, gravel has been as a foundation for centuries. In our case, it keeps the stone blocks and (more importantly) the wooden skids from resting in puddles of moisture, which could lead to mold and rot in your support beams.
After tamping the gravel to make sure the gravel is settled well, stone blocks are then laid out at even intervals along the trench. These stone blocks can be as simple as bricks or paving slabs, but most people prefer the pre-cast concrete forms you can pick up from your local hardware store.
Once the blocks have been arranged, pressure-treated wooden beams are then placed on top of the blocks and checked to make sure they are level with both the ground and each other. Then, the level must be checked in all horizontal and vertical directions. Finally, the subfloor is directly bolted to the skids, not the blocks.
Fast and simple to install, skid foundations aren’t without their drawbacks. While the non-anchored construction is popular with some tiny house owners because it gives them flexibility to move later on, it also means that they can only build on relatively flat, even ground. The gravel also has to be compacted extremely well before placing the blocks or beams, or else the foundation will fail as the gravel slowly shifts out of the way. However, this method of building has been done for centuries, and if done right, will last you for decades.
If you prefer to have a poured concrete slab or other non standard system, please contact your team leader for more information.