The Apex Truss Roof Estimating Calculator is used to calculate the Labour, Materials and Plant and costs associated with prefabricated truss apex roofs. All of the items required for an apex truss roof are specified from the Specification.

The Apex Truss Roof Estimating Calculator calculates the following items:

  • Roof trusses and bracing
  • Fascias and guttering
  • Tiling, sarking, felt undercloak and leadwork
  • Guttering and down pipes
  • Plastering and insulation
  • Internal and external decorating
  • Plus all labour associated with the above


  • Please pay particular attention to the Usage Factor for the roof tiling, which is highly variable for both labour and material and are particularly dependant on the roof tile selected. To modify Usage Factors, please take a look at Getting Started - Changing the Usage Factor of a Resource in a Specification
  • In addition, you should pay attention to the costs of the roof trusses, since their costs vary depending on the pitch and span.
  • The Apex Truss Roof Estimating Calculator can be used in conjunction with other roof types to create more complex roofs. Alternatively, you can use the Universal Truss Roof Estimating Calculator to estimate complex roofs which cannot easily be broken down into their constituent parts.