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Replacing a dome rooflight: measurements and photographs

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Safety first

Do not step on the dome or access an unprotected roof to take measurements. Leave work at height, damage inspection and work on smoke-exhaust systems to a qualified contractor. For an initial enquiry, the information and photographs you can obtain safely are enough.

Which dimensions matter?

  • Structural dimension K: the roof opening or structural dimension shown in the selected system drawing.
  • Clear dimension L: the unobstructed opening; the STELUX tables use O.
  • Nominal dimension N: the element size designation in its table.
  • Screw centres S: needed when checking replacement on an existing upstand.
  • Upstand height and shape: current condition and any change to the finished roof level.

Do not convert dimensions from memory. Mark the two measuring points for each dimension on a sketch and state the unit. Relationships differ between systems.

Which photographs help?

  • The complete element and its surroundings, from a safe position.
  • The dome-to-upstand junction and visible roofing finishes.
  • The opening from inside and any location of water ingress.
  • The opening mechanism and a readable identification label, if safely accessible.
  • Visible damage or distortion, without removing parts.

What can be retained?

An existing upstand or mechanism may be retained only after condition and compatibility checks. A new dome of approximately the same size is not proof of a correct fit. For smoke-exhaust systems, check the documented configuration of the complete device; do not substitute components arbitrarily.

How is the quotation prepared?

Send your information and describe the issue: damage, leaks, insufficient insulation or a faulty opening mechanism. We then agree on any necessary inspection and the replacement or repair solution. Manufacturing dimensions and the scope of work are confirmed before ordering.

Upstand shapes and dimensions · Send details for a quotation

Technical source: POS plastika catalogue “Svetlobne kupole in trakovi”, 2026 edition. The figures describe the specified catalogue configurations; confirm the exact build-up, dimensions and documentation before ordering.