“The yard slopes a little” gives a foundation chooser no repeatable site measurement. A useful record identifies where the high and low points are, how far apart they lie horizontally, and how much elevation changes across the proposed shed footprint. This is a field description, not a foundation recommendation.
Make a four-corner record
- Mark the proposed shed outline on a ground-level sketch. Label front left (FL), front right (FR), back left (BL), and back right (BR). Record the intended horizontal width and depth, not distances measured along the sloping ground.
- Choose one stable reference elevation. A level line or properly used laser level can transfer the same datum to each corner from a safe standing position. Record the vertical offset at each mark and the method used. Do not assume the fence, patio, or house siding is level.
- Repeat a doubtful reading. Note intervening humps, soft spots, drainage paths, retaining edges, and disturbed soil separately; four corners cannot reveal everything between them.
- Find the highest and lowest recorded corner. Their difference is total grade change. For a directional slope, divide the elevation change between a named pair by their horizontal run, then multiply by 100. State both endpoints with the percentage.
Shed site grade record · Site: __________ · Date: __________ · Datum: __________
Scroll the diagram sideways to read its labels.
| Corner | Example elevation vs. datum | Your reading | Condition note |
|---|---|---|---|
| FL (reference) | 0 in | ________ | ____________ |
| FR | −2 in | ________ | ____________ |
| BL | −5 in | ________ | ____________ |
| BR | −7 in | ________ | ____________ |
In this example, total high-to-low grade change is 7 in. If FL to BL is a 10 ft horizontal run, that direction changes 5 in / 120 in × 100 ≈ 4.2%. The FL-to-FR direction is 2 in over 12 ft ≈ 1.4%. Do not report “7 in over 10 ft” unless those actual high/low endpoints are 10 ft apart. Draw the direction arrows on the sketch so the figures are not detached from the site.
Carry the record into the next decision
Photograph the marked outline and retain the corner sheet, datum, measured runs, method, date, surface condition, and any drainage or access observations. Use those facts alongside the shed foundation chooser and in a shed manufacturer or installer discussion. The current chooser has no numerical slope input; it compares material paths only after the site and support details have been reviewed externally. It cannot infer soil bearing, frost behavior, erosion, drainage, settlement, or safe support from a slope phrase alone.
Pause the comparison and obtain manufacturer or qualified local review if the readings are inconsistent, the site has a retaining edge, fill, erosion, standing water, hidden utilities, a steep or irregular grade, or a structural/permit requirement you cannot verify. Do not excavate or build supports based only on this worksheet. Locate utilities before any digging and follow local requirements.