by rob@elementsofhome.com.au | Jun 29, 2023 | Uncategorized | 0 comments


A PC sum (Prime Cost Sum) and a PS sum (Provisional Sum) are both used in building contracts to allow for costs that cannot be accurately determined at the time of signing the contract. However, there are some key differences between the two.


  • A PC sum is used for items that have been selected, but the exact cost of the item is not known.
  • For example, you might have a PC sum for a specific brand of kitchen appliances, but the exact cost of the appliances will not be known until you order them.
  • The PC sum will typically include the cost of the item itself, as well as any associated labour costs.

 

  • A PS sum is used for items that have not yet been selected, or for work that has not yet been fully defined.
  • For example, you might have a PS sum for “site works”, which could include a variety of different items, such as excavation, landscaping, and drainage.
  • The PS sum will typically only include the cost of the materials, as the labour costs will not be known until the work is actually carried out.

In general, PC sums are more accurate than PS sums, as the exact cost of the item is known or can be estimated more closely. However, PS sums can be used to cover a wider range of items, and they can be more flexible if the scope of the work changes.


Here is a table that summarises the key differences between PC sums and PS sums: