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Pancyprian TS Qty Measurement study materials
Pancyprian TS Qty Measurement study resources

Pancyprian TS Qty Measurement: Roofing, Waterproofing and Thermal Insulation Measurement

Pancyprian TS Qty Measurement · Work through your exam, one topic at a time.

All guide sections

Roofing, Waterproofing and Thermal Insulation Measurement

Roofing is where plane-versus-slope errors are most expensive, and this domain tests whether you measure covering on the slope and linear items along the correct line. Waterproofing and insulation follow similar logic: area for the membrane, linear for the upstand.

Roof coverings

  • Measured in m² on the slope, never on plan. Side laps and end laps are included in the rate, not added as extra area.
  • Ridges, hips, valleys, eaves and verges are linear items described by type and material.
  • Profiled sheet and tile coverings state the gauge or pitch, the fixing and the substrate.

Waterproofing

  • Sheet and liquid membranes in m², with horizontal and vertical work classified separately; upstands, turn-ups and flashings are linear.
  • Protection layers, screeds and drainage layers are measured separately from the membrane itself.

Thermal insulation

  • Measured in m² with thickness and thermal conductivity stated; rigid board, quilt and full-fill cavity are distinct items.
  • Small areas are not deducted; tapered insulation states the slope or the minimum and maximum thickness.

Worked example

A symmetric pitched roof, span 8.000 m with a central ridge, pitch 30°, length 12.000 m. Half span = 4.000 m. Slope length = 4.000 / cos 30° = 4.000 / 0.866 = 4.619 m; both sides = 9.238 m. Covering area = 9.238 × 12.000 = 110.86 m². The plan area would be 8.000 × 12.000 = 96.00 m², some 15.5% short - a large under-measurement. Ridge = 12.000 m; eaves = 2 × 12.000 = 24.000 m; verges = 2 × 9.238 = 18.48 m measured along the slope. The cosine factor converts plan to slope; linear items that follow the slope use the slope length, not the plan length.

Traps that cost marks

  • Measuring the covering on plan and losing the pitch factor.
  • Adding laps as extra measured area instead of pricing them in the rate.
  • Missing flashings, upstands and rainwater outlets.
  • Mixing insulation area with membrane area where the extents differ.
  • Deducting rooflights below the threshold stated in the method.