What Happens on Site Before Your Dwelling Arrives
The step-by-step process from bare ground to crane day — what happens, when it happens, and what to expect at each stage.
If you’ve decided to build a modular secondary dwelling, there’s a phase of the project that most people don’t think much about until they’re in it: the weeks between committing to a build and watching a dwelling get craned into position on their property.
During this phase, your dwelling is being manufactured in a factory. But on your land, a different sequence of work is happening simultaneously — site investigations, engineering, earthworks, footing construction, service preparation and access logistics. This is the work that makes crane day possible. Skip any of it, rush it, or get it wrong, and the dwelling either can’t be placed, can’t be connected, or can’t be approved.
This guide walks through each stage of site preparation in the order it typically happens, with realistic timeframes and cost ranges for properties in South East Queensland. It’s written for the homeowner who wants to understand what’s actually going on, not just trust that someone else is handling it.
The Timeline at a Glance
On a straightforward acreage site with reasonable access and no major complications, site preparation typically takes 6 to 10 weeks from first investigation to crane-ready. On more complex sites — steep terrain, remote access, on-site wastewater, bushfire overlays — it can stretch to 12 to 16 weeks.
Most of this work runs in parallel with factory manufacture of the dwelling, so it doesn’t add to the overall project timeline. The goal is for the site to be ready when the dwelling is ready, not before or after.
| Stage | Typical Timing | Indicative Cost |
|---|---|---|
| Site assessment and soil test | Week 1–2 | $300–$600 |
| Survey and setout | Week 2–3 | $800–$2,000 |
| BAL assessment (if required) | Week 2–4 | $800–$2,000 |
| Service location and planning | Week 2–4 | Varies widely |
| Footing construction | Week 4–8 | $3,000–$12,000+ |
| Access and crane pad preparation | Week 6–8 | $1,000–$5,000+ |
| Pre-delivery inspections | Week 7–9 | Included in certifier fees |
| Crane day | Week 8–10 | $2,000–$6,000+ |
These are indicative ranges. Your site might be faster (flat suburban lot with sewer connection) or slower (steep rural block with on-site wastewater and restricted access). The point is to show the sequence and the relative timing, not to guarantee a schedule.
Stage 1: Site Assessment and Soil Test
This is where everything starts. Before anyone draws a footing plan or orders materials, the ground itself needs to be understood.
What Happens
A geotechnical engineer visits the property and drills test bores at the proposed building location. The number and depth of bores depends on the site, but for a secondary dwelling footprint it’s typically two to four bores to a depth of 2 to 3 metres. The samples are tested in a lab for soil type, bearing capacity, reactivity (how much the soil moves with moisture changes) and any problematic conditions like fill, rock or high water tables.
Why It Matters
The soil test results determine your footing design. Reactive clay needs different footings than sandy loam. Filled ground needs different treatment than undisturbed natural soil. Rock at shallow depth changes the engineering entirely. Without a soil test, the footing design is a guess — and getting footings wrong is expensive to fix after the fact.
On rural land, soil conditions can vary significantly even across a single property. The spot where the existing house sits might be completely different to the proposed dwelling location 50 metres away. Don’t assume.
Cost and Timing
$300 to $600 for a standard residential geotechnical investigation. Results typically take 5 to 10 business days from the site visit. This should be one of the very first things you do — ideally before you sign a building contract, so the footing cost can be accurately estimated.
Stage 2: Survey and Setout
Once you know where the dwelling is going and what the ground is doing, a licensed surveyor marks the exact position on the land.
What Happens
The surveyor establishes the dwelling footprint, finished floor level and setback distances from boundaries and existing structures. On acreage with no existing survey pegs, this may include re-establishing property boundaries. The setout provides the reference points that the footing contractor works to — it’s the translation from plan to ground.
Why It Matters
Setback distances are prescribed in the planning scheme and the Building Code. A secondary dwelling that’s 100mm too close to a boundary is a compliance failure that can be very expensive to resolve. On acreage where boundaries aren’t always obvious, the survey removes the guesswork.
The survey also establishes the finished floor level, which determines stormwater drainage, step-down to ground level, and accessibility. On sloped sites, this is particularly important — the level dictates how much cut and fill is needed and how the dwelling relates to the rest of the site.
Cost and Timing
$800 to $2,000 depending on the scope. A simple setout on a lot with existing survey data is at the lower end. A full boundary re-establishment plus setout on a large rural lot is at the higher end. Typically completed in one site visit with results provided within a few days.
Stage 3: BAL Assessment (If Required)
If your property is in a bushfire hazard overlay — and the majority of large lots in SEQ are — a Bushfire Attack Level assessment is required before building approval can be issued.
What Happens
A qualified bushfire consultant visits the site, classifies the surrounding vegetation, measures distances and slopes, and calculates the BAL rating for each elevation of the proposed dwelling. The report specifies what construction standards the dwelling needs to meet.
Why It Matters
The BAL rating directly affects material specifications, construction detailing and cost. It’s also a required document in the building approval package. We’ve written a dedicated guide to BAL ratings that covers this in full detail — assessment process, cost implications for each rating level, how to reduce your rating through site selection, and the insurance angle most people miss.
Cost and Timing
$800 to $2,000 for a full assessment. Allow 2 to 4 weeks for the site visit and report. This can and should run in parallel with the soil test and survey.
Stage 4: Service Location and Connection Planning
Your dwelling needs water, sewer (or on-site wastewater), electricity and potentially communications. Working out where existing services are, where the new connections will run, and who needs to do the work happens during this stage.
What Happens
Existing service locations are identified — typically through a Dial Before You Dig (DBYD) search and physical verification on site. The route from existing connection points to the new dwelling is planned, considering distance, depth, obstacles and any council or utility requirements. Quotes are obtained from licensed tradespeople for the connection work.
The Key Variables
Water. On suburban lots, the dwelling usually connects to the existing property’s water supply with a relatively short run of pipe. On acreage, the distance can be significant — 50 metres or more — and may require a booster pump if the main house supply doesn’t have adequate pressure at the dwelling location.
Sewer. If your property has a sewer connection, the dwelling will need its own connection to the sewer main or the property’s existing sewer line. Gravity flow matters — the dwelling’s drainage point needs to be higher than the sewer connection point, or you’ll need a pump system. On acreage without sewer, an on-site wastewater system (septic or similar) is required. This is a separate approval process and a significant cost — typically $10,000 to $25,000 depending on the system type and soil conditions.
Electricity. The dwelling needs its own metered electrical connection or a sub-board connection from the main house. If it’s a separate metered connection, the electricity distributor (Energex or Ergon in SEQ) needs to be involved, which adds time and cost. If it’s a sub-board connection, a licensed electrician runs a cable from the main switchboard. Distance and cable size determine cost.
Communications. Internet and phone are usually the simplest — a cable or conduit run from the main house, or a standalone connection if available. On rural properties, NBN fixed wireless or satellite may be the only options, which don’t require a physical cable to the dwelling.
Cost and Timing
Service connection costs vary enormously by site. On a suburban lot with short runs to existing services, you might be looking at $5,000 to $10,000 total. On an acreage property with long runs, new electrical connection and on-site wastewater, costs can reach $30,000 to $50,000. This is one of the biggest variables in total project cost, and it’s the main reason responsible builders won’t quote a single all-inclusive price without understanding your site. Planning and quoting happens in weeks 2 to 4, with physical work typically coordinated around footing construction.
Stage 5: Footing Construction
This is the largest physical piece of site work. The footings are the foundation system your dwelling sits on — they transfer the building’s loads into the ground and keep it level, stable and compliant.
What Happens
Based on the soil test results and the dwelling’s engineering specifications, a structural engineer designs the footing system. For modular dwellings, this is typically one of three types: concrete piers (bored into the ground and poured), steel screw piles (driven or screwed into the ground), or a combination system. On sites with rock at shallow depth, surface-mounted pad footings may be used instead.
The footing contractor excavates, sets and pours or installs the footings according to the engineering drawings. The surveyor’s setout marks provide the reference points. Once installed, the footings are inspected by the building certifier before the dwelling is placed.
Why It Matters
The dwelling arrives from the factory as a finished module (or set of modules) and is craned directly onto the footings. The footings need to be in exactly the right position, at exactly the right level, with the right load capacity. If they’re off by more than a few millimetres, the dwelling doesn’t sit properly. If the bearing capacity is wrong, the dwelling settles unevenly over time. Getting footings right is non-negotiable.
Cost and Timing
$3,000 to $12,000 or more, depending on soil conditions, footing type, number of piers and site access for the footing contractor’s equipment. Standard reactive clay sites with concrete piers are typically at the lower end. Sites with deep bores, difficult soil or steep terrain push costs higher. Construction typically takes 1 to 2 weeks, plus curing time for concrete (usually 7 days minimum before the dwelling can be placed).
Stage 6: Access and Crane Pad Preparation
Your dwelling arrives on a truck and is placed by crane. Both need to reach your building site, and that means the access route and crane setup area need to be ready.
What the Truck Needs
A modular dwelling is typically transported on a semi-trailer or extendable trailer, depending on the module dimensions. The access route from the public road to the building site needs to accommodate a vehicle that’s up to 25 metres long, 3.5 to 4.5 metres wide (depending on whether an escort vehicle is used) and requires a turning radius of approximately 12 to 15 metres. On acreage with existing driveways, this is usually manageable. On properties with narrow gates, tight corners, overhanging trees or soft ground, preparation work may be needed — widening a section of driveway, trimming branches, stabilising a soft patch or temporarily removing a fence panel.
What the Crane Needs
The crane sets up adjacent to the building site. It needs a firm, level area to operate from — typically a cleared space of approximately 8 metres by 12 metres with ground capable of supporting the crane’s weight (which can be 40 to 80 tonnes depending on the crane size). On established properties, this might be an existing hardstand area or driveway. On raw acreage, a crane pad may need to be prepared — compacted gravel or crushed rock on stable ground.
The crane operator will typically visit the site beforehand to confirm the setup position, lifting geometry and any overhead obstructions (power lines are the most common issue). If power lines need to be temporarily relocated or de-energised, this requires coordination with the electricity distributor and adds time and cost.
Cost and Timing
Access preparation varies from nothing (existing driveway and hardstand are adequate) to $5,000 or more (driveway widening, crane pad construction, tree trimming). The crane itself typically costs $2,000 to $6,000 depending on crane size, travel distance and placement complexity. Multi-module dwellings that require multiple lifts cost more. Allow 1 to 2 weeks for access preparation work, and book the crane well in advance — crane availability in SEQ can be tight.
Stage 7: Pre-Delivery Inspections and Approvals
Before the dwelling can be placed, certain approvals and inspections need to be completed.
Footing Inspection
The building certifier inspects the completed footings against the engineering drawings. This confirms that the footings are in the right position, at the right level and built to the right specification. This inspection must pass before the dwelling is placed. If the footings don’t comply, they need to be rectified first.
Building Approval
The building approval (issued by the private building certifier) must be in place before the dwelling is delivered. This is the approval that confirms the dwelling design complies with the Building Code of Australia and relevant Queensland Development Code provisions. If a development application was required (because of overlays or non-compliance with accepted development criteria), the council approval must also be in hand.
Transport Permits
Oversize loads on Queensland roads require transport permits from the Department of Transport and Main Roads. Your builder or transport contractor arranges these based on the dwelling dimensions and the route from the factory to your site. Escort vehicles may be required for wider loads. Weekend or early-morning delivery is common to minimise traffic disruption.
Crane Day: What to Expect
This is the day most people have been waiting for — and it’s typically the shortest, most visible piece of the entire process.
The dwelling arrives on the transport vehicle, usually early in the morning. The crane is already set up on site (or arrives and sets up first thing). The dwelling module is lifted from the truck, swung into position and lowered onto the prepared footings. For a single-module dwelling, this process typically takes 2 to 4 hours from the truck arriving to the module being in position. Multi-module dwellings take longer — each module is placed individually and then joined on site.
Once placed, the dwelling is secured to the footings using the engineered connection system (typically bolted brackets). The crane and transport vehicle leave, and what was bare ground that morning now has a building on it.
It’s surprisingly fast. The weeks of site preparation are invisible by this point — the footings are underground, the services are roughed in, the access has been prepared. Crane day is the payoff for all of that groundwork.
After Placement: What Happens Next
The dwelling is on the footings, but it’s not finished. Several things need to happen after placement before you can move in or hand over the keys.
Service connections. Water, sewer (or wastewater), electrical and communications are physically connected to the dwelling. Plumbing and electrical connections that were roughed in during site preparation are now completed and commissioned.
Skirting and subfloor. Depending on the footing type and the design, skirting or subfloor enclosure may be installed after placement. This is common on pier-and-beam footing systems where the dwelling sits above ground level.
External works. Steps, landings, decking, pathways and any required landscaping or stormwater management are completed. These are typically specified in the building approval and need to be in place before the final inspection.
Final inspection. The building certifier conducts a final inspection of the completed dwelling — including all connections, external works and compliance items. If everything passes, the certifier issues a Form 21 (Final Inspection Certificate), which is the document that confirms the building is compliant and can be lawfully occupied.
Practical completion. Once the Form 21 is issued, the dwelling is legally ready for occupation. Any remaining items — minor touch-ups, appliance installation, final cleaning — are completed, and the project is handed over.
From crane day to practical completion is typically 2 to 4 weeks, depending on the complexity of service connections and external works.
Further Reading
- Building a Secondary Dwelling on Acreage in SEQ — the comprehensive acreage guide covering zoning, approvals, site prep and timelines
- How Much Does a Secondary Dwelling Cost in Queensland? — full cost breakdown including site costs, council fees and hidden costs
- BAL Ratings Explained — deep dive into Bushfire Attack Levels, how they’re assessed and how they affect construction
- What Is a Secondary Dwelling? — the foundational definition piece, including building classifications and approval pathways
- Granny Flat vs. Secondary Dwelling vs. Modular Home — terminology guide explaining what the different terms actually mean
- Secondary Dwelling Size Limits by Council — SEQ 2026 Guide — council-by-council size limits and infrastructure charges
About Outhaus
Outhaus builds Class 1a modular secondary dwellings for acreage properties across South East Queensland. We’ve been through every stage described in this guide on our own land — three dwellings on a 500-acre working cattle farm at Laceys Creek, complete with reactive clay, bushfire overlays and a 2-kilometre driveway. We know what the site preparation process looks like because we’ve lived it. If you want to talk through what your specific site would involve, we’re happy to have that conversation before anything gets formal.