PC and PS Items Explained: What They Mean For Your Melbourne Build
Prime Cost (PC) items are budget allowances for products you haven't chosen yet, such as tapware or tiles, while Provisional Sum (PS) items are estimated allowances for work that's hard to price exactly before it starts, such as excavation or demolition. Both appear in fixed price building contracts and are adjusted once real costs are confirmed.
If you're planning a renovation, extension or new home build in Melbourne, you've probably seen "PC" or "PS" next to a dollar figure in your tender or contract. These terms aren't a builder's trick to hide costs — they're a standard part of Australian domestic building contracts, used because some decisions genuinely can't be locked in on day one. Understanding how they work helps you read your contract with confidence and avoid surprises down the track.
At Transform Homes, the design and selections phase is built around finalising as many of these decisions as possible before a fixed price tender is issued. That's why it's worth understanding what PC and PS items are, how they're calculated, and what happens if the final cost differs from the allowance.
What Is a Prime Cost (PC) Item?
A Prime Cost item is a dollar allowance built into your contract for a fixed, specific product that hasn't been selected yet — usually because you need to see options in person or a supplier lead time means the choice is left open. Common PC items include:
- Tapware and bathroom fittings
- Tiles
- Kitchen appliances
- Light fittings
- Door and cabinet hardware
The allowance is based on a reasonable market price for that category of product. Once you choose the actual item, the contract price is adjusted up or down to reflect the real cost.
What Is a Provisional Sum (PS) Item?
A Provisional Sum is an allowance for work or services that can't be accurately priced until the job is underway — usually because the scope depends on site conditions that aren't visible until work starts. Common PS items include:
- Excavation and site works
- Demolition – eg asbestos
- New Stormwater connections to council assets
- Rock removal or unexpected ground conditions
Because PS items relate to labour and site conditions rather than a product you pick from a catalogue, the final figure is confirmed once the work is actually carried out or properly quoted.
What's the Difference Between PC and PS Items?
Why Do Builders Use PC and PS Items?
PC and PS items exist so a fixed price contract can still be signed even when a small number of details genuinely aren't finalised yet. Without them, a builder would either have to guess (and risk under-quoting) or delay signing the contract until every tap and tile is chosen. Used correctly, they protect both the client and the builder from disputes over cost blowouts, because the allowance and the adjustment process are agreed to upfront, in writing.
How Does Transform Homes Handle PC and PS Items?
Transform Homes structures the build process to reduce the number of open allowances left in your contract. During the Design & Selections stage — before any fixed price tender is prepared — our clients work through colour selections, supplier appointments, working drawings and specifications with the team. The aim is to have a complete and confirmed set of plans and specifications before pricing happens, which means fewer decisions are left as PC or PS allowances once you sign.
Where an allowance is unavoidable (for example, a site condition that can only be confirmed once excavation begins), any adjustment is handled through Transform Homes' documented variation process: the change and its cost or time impact is quoted and explained, and nothing proceeds until you've signed off.
What Happens If the Actual Cost Is Different From the Allowance?
- You select the product (for PC items) or the trade completes an assessment (for PS items).
- The actual cost is compared against the allowance already in your contract.
- If the real cost is higher, you're invoiced the difference; if it's lower, the difference is credited back.
- The adjustment is documented in writing before it's added to your contract — this is standard practice for any variation.
- You have the opportunity to review and approve the change before it proceeds.
Do PC and PS Items Affect My Fixed Price Contract?
Yes, but only within the categories already listed as allowances — they don't change the overall structure of a fixed price contract. The rest of your build (labour, materials, and scope outside the PC/PS items) remains fixed. PC and PS items simply mark out the specific areas where the final figure depends on a selection you make or a condition uncovered once work starts.
How does Transform Homes Minimise PC and PS Adjustments on My Renovation or New Build?
- We encourage product selections being made as early as possible during the design phase.
- We undertake a site inspection and soil test upfront to gain as much understanding as possible of the soil profile early in the design.
- We ensure that allowances reflect realistic, current supplier pricing.
- We keep communication open between you and your project manager so selections don't stall the schedule.
If you're planning a renovation, extension or new home in Melbourne's northern suburbs and want a clearer picture of how allowances may apply to your project, the Transform Homes team can walk you through your specific plans and site conditions before you sign anything.
Contact Transform Homes today to start planning your build with a clear pathway from construction through to handover including minimised PC and PS items.
About the Author
Greg brings nearly 25 years of experience in the building industry, with extensive knowledge across residential and commercial construction projects.
His experience spans project planning, construction and practical building management, with a strong focus on quality, craftsmanship, professionalism and attention to detail.
Through his writing, Greg shares practical building advice and industry insights to help homeowners make informed decisions when planning and building their homes.
