Even coursing for lap siding — avoiding the sliver top row under the soffit

Running every board at max exposure leaves an ugly sliver under the soffit. Even coursing shrinks the reveal just enough (108″ ÷ 16 = 6¾″) so all courses are equal and the top one lands clean at the eave.

Two wall elevations of the same 108-inch-tall wall compared. On the left (wrong), every board runs at its maximum 7-inch exposure, so after 15 full courses only a 3-inch sliver is left jammed under the soffit — an ugly cut that is hard to nail. On the right (correct), the exposure is reduced slightly to 6¾ inches so that 16 equal courses fill the wall and the top course lands cleanly at the eave. The adjusted exposure is the wall height divided by the course count: 108 inches ÷ 16 = 6¾ inches. — Source: Even-coursing layout — manufacturer installation guides

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Two wall elevations of the same 108-inch-tall wall compared. On the left (wrong), every board runs at its maximum 7-inch exposure, so after 15 full courses only a 3-inch sliver is left jammed under the soffit — an ugly cut that is hard to nail. On the right (correct), the exposure is reduced slightly to 6¾ inches so that 16 equal courses fill the wall and the top course lands cleanly at the eave. The adjusted exposure is the wall height divided by the course count: 108 inches ÷ 16 = 6¾ inches.

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    <img src="https://remodelcalculators.com/api/figure-embed/siding-even-coursing" alt="Two wall elevations of the same 108-inch-tall wall compared. On the left (wrong), every board runs at its maximum 7-inch exposure, so after 15 full courses only a 3-inch sliver is left jammed under the soffit — an ugly cut that is hard to nail. On the right (correct), the exposure is reduced slightly to 6¾ inches so that 16 equal courses fill the wall and the top course lands cleanly at the eave. The adjusted exposure is the wall height divided by the course count: 108 inches ÷ 16 = 6¾ inches." width="800" height="480" style="width:100%;height:auto;border:0" loading="lazy">
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    Diagram: <a href="https://remodelcalculators.com/construction-diagrams/siding-even-coursing" target="_blank" rel="noopener">Even coursing for lap siding — avoiding the sliver top row under the soffit</a> — courtesy of <a href="https://remodelcalculators.com" target="_blank" rel="noopener">RemodelCalculators.com</a>
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