Site cost allowance feels like a number they made up

slab-happens

Signed a prelim agreement for a build in Armstrong Creek and the site costs line is a $28,000 provisional sum. Asked how they got there and the sales guy basically shrugged and said standard for the estate.

Neighbour two streets over paid $41k on what looks like the same dirt. A mate on a flat block in Torquay paid $15k. Nobody can explain to me what actually drives the number, its just a figure that appears on page 3 and eats your upgrade budget.

What was your site cost allowance vs what you actually paid? And did anyone manage to get a builder to show working, like the soil class they assumed and how much fall they priced for?

Starting to think the provisional sum is less of an estimate and more of a mood.

gumleaf_88

Ask them in writing what the PS assumes. Soil class, site fall over the pad, depth of fill, distance to sewer and stormwater connection points. A real estimate has those numbers behind it. If the answer is our estimator uses standard allowances, thats a guess with a letterhead.

Get your own soil test and contour survey before contract if they will let you. Costs a couple of grand and turns the PS into something you can argue with. On site the jobs that blow out are nearly always fill and rock nobody priced, not the slab itself.

fuzzy-muppet

PROVISIONAL SUM IS LATIN FOR WE WILL TELL YOU LATER

mate of mine got quoted 22k, paid 39k. the extra 17k was discovered after the contract was signed. discovered. like it was archaeology and not a number they lowballed to win the job

soil test BEFORE you sign. hill to die on

dirt-and-dreams

We are land shopping in Clyde North and started asking every developer for the geotech report and the engineering plans for the stage. Some hand them over same day, some suddenly get vague. That reaction tells you a lot on its own.

One sales office told us soil reports are commercially sensitive. For dirt. Righto.

slab-happens

update: pushed the builder and got the assumptions in writing. the 28k assumes class M and 300mm of fall. our contour survey says 900mm of fall across the pad, so that number was never going to survive contact with the excavator.

redoing the sums with the site supervisor next week before we sign anything. cheers for the push everyone, honestly felt like i was being difficult until this thread

slab-happens

We just got the revised site cost figure after the contour survey. Started at 28k provisional, came back at 46k once they priced the actual fall and a patch of rock the salesman swore was not there.

Useful tip from our supervisor: ask for the site cost schedule as a line item list, not one lump. Ours had excavator hours, spoil cartage, piering contingency and stormwater separately. Suddenly the mood number became something you could argue with.

estatelife-em

Reading this thread before signing saved us real money. Asked for the PS assumptions in writing like suggested and the builder quietly revised the site allowance up 9k before contract instead of springing it at slab stage.

Painful to see the bigger number early but at least the bank got asked for the right amount once.

gumleaf_88

One more ask before you sign: get the site cost schedule as a PDF you can mark up, not a single line on page three. Ours had cartage and piering buried under a vague prelims heading.

Once it was split out we could argue two of the lines against the contour survey. Shaving 4k felt petty until it was not.

HazzaB-QLD

Ripley tip that saved us: ask whether the provisional sum includes rock contingency or whether rock is a separate schedule. Ours did not, and the excavator found it on day two.

Once that line was visible we could price a second opinion before signing the variation.

HazzaB-QLD

Ripley again: final site cost landed 11k over the revised allowance once cartage and a short pier run were invoiced. Painful, but not the mystery lump it started as.

Keeping the schedule as a marked up PDF through the whole job was the only way I could argue two of the lines.

HazzaB-QLD

Ripley wrap: final site cost invoice closed 12.4k over the revised allowance after cartage and one pier variation. Ugly spreadsheet, but every line now has a photo and a date.

If you are still at contract stage, ask for the soil class and fall assumptions in writing before you celebrate the headline site figure.

HazzaB-QLD

Ripley quiet update - landscaper finally finished the falls away from the slab edge and the last of the site cost drama is off my desk. Would still tell anyone at contract stage to get soil class + fall assumptions written down before celebrating the site figure.