Enter the room dimensions and see detector count and positions live on the floor plan — the same tested calculation as in the PlanWerke planner, to the parameters of DIN 14676. Free, no sign-up, entirely in your browser.
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The detector count is the room area divided by the coverage area per detector, rounded up. To the parameters of DIN 14676 that coverage is between 60 and 150 m² — depending on room size, ceiling height and roof slope; the calculator shows the applied value.
Every point of the room must lie within the coverage radius D_H of a detector; a minimum clearance of 0.5 m applies to walls. Angled rooms therefore sometimes need more detectors than the area formula yields.
Corridors up to 3 m wide follow additional spacing rules: at most 15 m between two detectors, at most 7.5 m from the corridor end to the nearest detector.
In living rooms of ordinary size one smoke alarm is usually enough: up to 80 m² of floor area, DIN 14676 assigns a coverage area of 80 m² per detector. Larger rooms are divided by area and rounded up — a 126 m² room with a 3.2 m ceiling needs 3 detectors, for example (126 ÷ 60 = 2.1, rounded up 3). Angled rooms can require additional detectors through the geometry check.
The calculator uses the same tested computation as the PlanWerke planner: coverage area per detector to the parameters of DIN 14676 — depending on floor area, ceiling height and roof slope — plus the coverage radius D_H and 0.5 m minimum clearance to walls. The computation runs locally in your browser; no data is transmitted.
Yes. Setting the room type to “corridor” applies the special rules for narrow corridors: at most 15 m between two detectors and at most 7.5 m from the corridor end to the nearest detector — in addition to the area rule.
No. The result is a standards-oriented sizing aid — a planning proposal for professional review. Beams, fixtures, ceiling coffers and irregular shapes can change the placement; planning responsibility remains with the engineer.
No account required · runs entirely locally in your browser