Recommendation: shortlist Ironbark. It is the only tender that prices the whole set. Kestrel is $52,500 under the plan on paper but leaves out site cut and fill and carries a joinery allowance $38,000 under the plan; adjusted, it lands $6,900 over Ironbark. Southgate's number is not real: 14 exclusions and a $45,000 provisional sum for the roof push it $39,400 above Ironbark once made like-for-like. Ask the three questions in section 5 before you recommend, and ask Ironbark to hold its price for 30 days.
Thin = priced more than 15% under the plan without an explanation in the tender. Heavy = more than 15% over. Silent = not priced and not excluded, so it is in nobody's number. Figures ex GST.
| Trade | Cost plan | Kestrel | Ironbark | Southgate |
|---|---|---|---|---|
| Preliminaries and supervision | 168,000 | 152,000 ok | 176,500 ok | 118,000 thin |
| Demolition and site cut / fill | 42,000 | — silent | 44,800 ok | excluded |
| Concrete, slab and footings | 96,000 | 101,200 ok | 98,400 ok | 92,500 ok |
| Carpentry, framing and roof structure | 188,000 | 181,000 ok | 194,200 ok | 171,000 ok |
| Roofing and rainwater | 48,000 | 46,500 ok | 49,900 ok | PS 45,000 PS |
| Windows and external doors | 112,000 | 108,900 ok | 114,300 ok | 96,000 thin |
| Cladding and external finishes | 74,000 | 79,800 ok | 72,100 ok | 61,000 thin |
| Plumbing and drainage | 58,000 | 56,200 ok | 61,000 ok | 54,000 ok |
| Electrical and data | 52,000 | 49,800 ok | 55,600 ok | 38,900 thin |
| Heating, cooling and ventilation | 46,000 | 61,000 heavy | 47,200 ok | excluded |
| Plaster and internal linings | 54,000 | 52,700 ok | 55,900 ok | 49,000 ok |
| Joinery | 98,000 | 60,000 thin | 96,500 ok | PC 55,000 PC |
| Tiling, waterproofing and stone | 44,000 | 43,100 ok | 46,800 ok | 39,000 ok |
| Painting | 32,000 | 30,500 ok | 33,400 ok | 27,600 ok |
| Floor finishes | 28,000 | 27,200 ok | 29,100 ok | excluded |
| Fixtures, fittings and appliances (PC items) | 38,000 | 38,000 | 38,000 | 38,000 |
| External works and landscaping | excluded | excluded | excluded | excluded |
| Margin and overheads | 162,000 (15%) | 99,600 (9%) | 148,300 (13%) | not stated |
| Tender as submitted | 1,240,000 | 1,187,500 | 1,262,000 | 1,098,000 |
| Item | Plan allowance | Kestrel | Ironbark | Southgate | Exposure |
|---|---|---|---|---|---|
| Rock excavation (PS) | 12,000 | not carried | 12,000 | excluded | Site has a known rock shelf. A tender without this item will claim it. |
| Joinery (PC / package) | 98,000 | 60,000 | 96,500 quoted | PC 55,000 | Under-allowed joinery is the commonest post-contract blowout on this house type. |
| Roofing (PS) | priced | priced | priced | PS 45,000 | A PS against fully documented work means the builder has not priced it. |
| Tapware and sanitary (PC) | 18,000 | 18,000 | 18,000 | 18,000 | Consistent. Selections still to be made. |
| Appliances (PC) | 20,000 | 20,000 | 20,000 | 20,000 | Consistent. |
| Kestrel | Ironbark | Southgate | |
|---|---|---|---|
| As submitted | 1,187,500 | 1,262,000 | 1,098,000 |
| Silent and excluded scope added at plan allowances | + 54,000 | — | + 158,400 |
| Under-allowed items brought to plan | + 38,000 | — | + 45,000 |
| Provisional sums realistically assessed | — | — | — |
| Margin below 12% normalised | — (noted, not added) | — | not stated |
| Like-for-like | 1,268,900 | 1,262,000 | 1,301,400 |
| Against the cost plan | +2.3% | +1.8% | +5.0% |
To Marlowe Architects · Re Hillview Residence tenders · 26 Sep 2026
Three tenders were received against the Rev C set. Assessed like for like, they sit within 2% to 5% of the pre-tender cost plan of $1,240,000, which says the documents were priced fairly and the plan was sound.
Ironbark Constructions at $1,262,000 is the only complete tender and is recommended for shortlisting. Kestrel Build's $1,187,500 becomes $1,268,900 once site works and joinery are made real, and its margin is thin enough to expect variations. Southgate Homes' $1,098,000 is not comparable as submitted.
Before recommending Ironbark to the client, obtain written answers to the two questions in section 5 and a 30-day price hold. If Kestrel answers its three questions with figures inside the plan's allowances, it becomes a genuine second option.
Prepared by Costd from the tender documents, the addenda and the pre-tender cost plan. An opinion of probable cost and tender completeness, not a quotation or legal advice. Costd is a service of Building Integrity Group Pty Ltd, registered builder.