Planning properly is immensely important for building a tiny house. I started the tiny house foundation layout after I had a detailed sketch of the house I wanted to build, a materials list and a stockpile of all necessary building supplies. Invest in a laser level and it will make your build much easier. Surveying properly will pay dividends in making the build go smoothly. I recommend double and triple checking everything.
Pro tip: use your laser level at dusk it will make seeing the laser much easier.
How do I set the perimeter of the tiny house foundation layout?
The first step is to mark the outer perimeter of the tiny house. Make sure the edge of the perimeter isn’t too close to the edge of the property or other hazards. Be mindful of nearby trees as they may grow to be a nuisance in future years. You want to place stakes in the 4 corners of the perimeter of the house.
I wanted my tiny house to be parallel with my other house so I started measuring off wall of the other house. Equal measurements from the other house to my stakes ensured both stakes were parallel with the house.
The side of the tiny house that I wanted to be parallel with the other house was going to be 24 ft long. I measured 24 feet and placed a stake on both ends to double check if the stakes were parallel with the house. I then ran a string line between the 2 stakes.
From the 2 stakes I measured 8 ft at 90 degrees perpendicular to create the width of the perimeter. Use a square to make sure your measuring tape is perpendicular 90 degrees. I put a stake down 8ft from the original stake on both sides of the perimeter. This may take some trial and error to make sure the measurements are exact and the stakes are perfectly 90 degrees.
How do I double check my tiny house foundation layout?
If I did everything properly these stakes should be parallel with the other stakes. The length sides of the building should measure 24 feet from stake to stake The width sides should run 8 ft from stake to stake. The 24 foot sides should be parelel with each other. The 8ft sides should be parellel with each other.
The ultimate test is the run a measuring tape from one corner to the other corner across the square. Then measure the opposite corners. If these two measurements are the same this means the perimeter is perfectly square.
You want high precision. Double and triple check everything. Finish by running a string line from stake to stake along the perimeter. You can also spray paint the ground under the string line to make sure you have an idea where the perimeter is.
How many piers do I need?
| Layout dimensions in feet | 8’x16′ | 8’x20′ | 8’x24′ | 13’x13′ | 18’x18′ |
| How many piers needed | 6 | 8 | 10 | 9 | 16 |
How do I place my pier holes?
Now that I had a perimeter the next step was to make markings for all the pier holes. My design was going to have the house on skids so I needed to make 2 rows of piers running lengthwise for the posts to fit into. The skids are running lengthwise so it can be potentially loaded on a truck later.
Since the width of my house was 8 ft I needed to space out the piers to accommodate for the strength of 2×10 lumber. For 2×10 lumber you don’t want more than a 6 foot span between piers. So I decided for each row of piers to be 1 foot in from the 8 ft width of the perimeter of the house. After subtracting 1 foot on either side this left a 6 ft span in the middle widthwise.
The same rule applies for the distance between piers lengthwise of the house. The length of the house was 24 feet so I chose 5 piers in each row for 10 piers total. This would break down to 4.8 ft between each pier lengthwise(24ft).
How do I space the piers?
I had four 12ft long 4×6 beams to create beams. This meant the middle beam needed hold the end of the beams both beams. I placed the beams in the perimeter for a mock up just to line up the exact location of each pier. Overall for a 192 square foot house I had 10 piers so each pier is supporting 19.2 square feet.
I measured one foot inward from the edge of the perimeter lengthwise and made a straight line that would be the middle of the piers. Make sure to use a stringline to mark these lines from end to end. I then evenly spaced the 5 markings for the piers along each line.
Double check that the markings line up both lengthwise and widthwise. I cut a small piece off of the pier tube to use as a marker for spray painting a circle on the ground. The pier tube should be 12” in circumference.
How do I mark the measurements?
I spray painted the 10 circles on the ground along the two lines I marked. I then double checked if they were lined up with each other widthwise and lengthwise. At this point I had all of the circular markings lined up. They were in a perfect grid lined up lengthwise, widthwise, 1 foot from the perimeter and spaced evenly. I cant stress enough to triple check your work as the next step is to drill the holes.
Accuracy is key when planning tiny house foundation layout
Having accurate measurements in you tiny house foundation layout will make sure all construction down the line will go as plan. Planning the structure on paper as well as on the ground at the job site will make next steps easier.
Next Step: Building the Foundation
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