The Roof Renovation Estimating Calculator is used to calculate re-roofing any shape of roof. This Estimating Calculator can be used to estimate the Labour, Materials, Plant and associated costs involved in stripping the roof structure and tiles and re-fitting timbers, tiles, soffits and fascias etc.

The Roof Renovation Estimating Calculator calculates the following items:

  • Carcassing timber
  • Fascias and guttering
  • Tiling, felt undercloak and lead work
  • Guttering and down pipes
  • Plastering and insulation
  • Internal and external decorating

All of the items required for the Roof Renovation Estimating Calculator are specified from the Specification.

To estimate a roof using the Roof Renovation Estimating Calculator, enter dimensions as appropriate and specify which Materials are to be replaced. Note that not all of the options will be appropriate to every roof as they allow for a range of possible roof shapes and specifications.


  • 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, take a look at Getting Started - Changing the Usage Factor of a Resource in a Specification.
  • In addition, you should pay close attention to the timber sizes, which are highly variable.