Obstructions Against Walls - MeyerFire

Sentry Page Protection

Obstructions Against Walls checks a sprinkler positioned near a wall-mounted obstruction — a soffit, ledge, or similar projection — against the NFPA 13 obstruction-against-wall rule.

Enter the condition:

Configuration — sprinkler type and NFPA 13 edition set which figure and rule apply.
Obstruction Geometry — B (vertical, deflector to bottom of obstruction), D (obstruction width), and A (horizontal to the sprinkler).

The tool applies the correct figure, computes the minimum horizontal distance the sprinkler must be set from the obstruction, flags a narrow obstruction (≤ 24 in / 600 mm, exempt from added protection), and tells you whether a sprinkler is required below the obstruction — drawn to scale in the section view.

Toggle US / SI units, export the section as PNG (transparent) or PDF, or Print a one-page report.

Click below to download the PDF guide.

See an odd result or have a suggestion to improve the tool?

Email us at [email protected] .

Go to the Ceiling Obstruction Calculator

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