The PVCu Replacement Window Estimating Calculator should be used to estimate the Materials, Labour and Plant required to replace a PVCu window.

 This Estimating Calculator is linked to the Specification. Therefore many of the items required for the window are specified from the Specification you have chosen.

The combination of resources taken from the Specification and the dimensional information will then calculate the following items automatically:

  • Frame fixings
  • Plastering
  • Window boards
  • Decorating

To estimate multiple windows of the same size, enter the number of windows when prompted. For example, if you were estimating three 600 x 1200 windows, you would enter 3. This multiplies all Materials, Labour and other associated Resources by three and consequently increases the cost threefold.


  • Before accepting the output, you should check all the pre-specified items, and in particular any items that are highlighted in red to show that they are “critical items” in the Calculated Resources tab.
  • In addition to the pre-specified items you must also carefully scrutinise the Sundry Resources tab. This tab covers the more freeform aspects of the window such as the window type, lintel and the labour for fixing the various types of window, which are not necessarily directly linked to the dimensions you have entered. 
  • If the size of the opening is changed you must check the suitability of the selected window, frame and lintel etc.