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Rooflight upstands: selection and roof connection

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Straight, tapered or KNICK?

For the illustrated configurations, the catalogue gives these relationships between structural dimension K and clear dimension L:

  • Tapered upstand: L = K − 20 cm.
  • KNICK upstand: L = K − 11 cm.
  • Straight upstand: L = K.

At K = 100 cm, the illustrated cross-section therefore gives clear dimensions of 80 cm, 89 cm and 100 cm respectively. This explains the catalogue geometry; it is not an instruction to form an arbitrary roof opening. Use the drawing for your selected system before manufacture.

Material and thermal insulation

The range includes glass-fibre-reinforced polyester and metal upstands. For the standard upstand, the catalogue specifies 2.5 cm insulation and U = 0.83 W/m²K. This value applies to that upstand, not to the complete dome and roof junction. Special versions can include additional insulation, an insulated flange, base or drip detail.

Choose height for the finished roof

Standard polyester upstand heights are 15, 30 and 50 cm. None is a universal choice for every roof. Consider the new or refurbished roof build-up, insulation thickness and waterproofing termination. The designer, roofing contractor and rooflight supplier should coordinate the final detail.

Take particular care during refurbishment

Additional roof insulation changes the relationship between the upstand and finished roof level. Tell us if roof refurbishment is planned alongside dome replacement. Fixings, upstand condition, opening options and space for safety equipment also need checking.

Information for selection

Prepare the dome or continuous rooflight type, structural and clear dimensions, roof section, insulation thickness and photographs of the existing junction. Add any requirements for ventilation, roof access, or natural smoke and heat exhaust.

Technical drawings and upstand 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.