Minimum lot size
Many zones set a floor on the area needed per dwelling or per subdivided lot. A block that is just under the threshold yields one dwelling; two combined can clear the bar with room for three or four.
The best development site on a street often is not for sale, and often is not one site at all. It is two or three ordinary blocks that, on their own, each fall just short — too narrow for a driveway, too small for the density the zone allows, one frontage short of what the code demands. Put them together and the maths changes: the combined parcel clears the thresholds, carries more dwellings, and commands a land premium neither owner could get alone. That is site amalgamation, also called land assembly — and finding those combinations first is a real edge.
The hard part is spotting them. You cannot eyeball a suburb and know which runs of adjoining lots quietly unlock extra yield when combined; you would have to read the cadastre parcel by parcel and re-run the yield test for every plausible grouping. This page explains what amalgamation is, how to spot assembly opportunities, exactly how GoSiteHunt's Amalgamations engine finds adjoining-lot groups and quantifies the upside, the owner-agreement and planning realities you cannot skip, and how residential assembly differs from retail and mixed-use.
What site amalgamation actually is
Site amalgamation is combining two or more adjoining lots into one larger development site so the whole outperforms the sum of the parts. It is a planning and acquisition play, not a construction one. The value is created the moment the parcels are consolidated — because a bigger, wider, more regular site can support a scheme the individual blocks legally or physically cannot.
Three constraints drive almost every assembly opportunity, and they are the reason single blocks so often miss out:
Frontage and shape
Density controls, setbacks and access rules reward width and regularity. Two narrow lots side by side give the combined frontage that makes a driveway, a common access, or an efficient built form possible.
Density and yield
Above a certain site area, apartment and townhouse controls open up. Assembly is often the only way to reach the footprint where the higher-yield product the zone permits actually becomes buildable.
Because a combined site does what the singles cannot, it draws stronger developer interest and a premium over the sum of the individual land values. That premium is the whole economic reason assembly exists — and the reason an owner will sometimes accept a deal only if their neighbour is in it too.
How to spot assembly opportunities
Manually, land assemblers look for a pattern: a cluster of modest, similar-vintage blocks in a zone that permits more than they hold, where no single lot is big or wide enough to justify redevelopment but a run of two-to-four adjoining ones would be. Corner holdings, deep back gardens and older lots in an up-zoned corridor are classic tells. The skill is reading the cadastre and the controls together and asking, for every plausible grouping, "does combining these cross a threshold that unlocks yield?"
Doing that by hand across a suburb is slow and easy to get wrong — exactly the work worth automating. The signal is not "this block is big"; it is "these specific neighbours, combined, screen at more than they do apart" — a comparison across every adjoining grouping, re-run on zone-typical yield numbers. That is what the Amalgamations engine computes at scale.
Exactly how GoSiteHunt's Amalgamations tool works
Inside GoSiteHunt the Amalgamations tool lives on the /sites screen behind the "🧩 Amalgamations" button, and a run costs 5 credits. You give it an address; it reads the cadastre around that address and finds groups of neighbouring or adjoining lots that, combined, support a bigger scheme — more dwellings, or more subdivision lots — than each block does separately. This is the classic land-assembly play, computed for you instead of eyeballed.
For every candidate lot-group it returns a compact, decision-ready result:
- The lots in the group — which specific adjoining parcels combine to make the play.
- Combined site area (m²) — the consolidated area the yield test is run against.
- Units or lots the combined site screens at — how many dwellings or subdivision lots the merged parcel supports on zone-typical numbers.
- The uplift — the extra yield versus everyone developing separately, expressed as a figure such as "+6", so you can rank groups by how much assembly actually adds.
- A polygon map — each lot-group drawn on the map so you can see the shape, frontage and context at a glance.
A suburb of individual blocks becomes a ranked set of combinations — the runs of adjoining lots where consolidation crosses a threshold and adds yield, sorted by the uplift they create. You are no longer guessing which neighbours belong together; the engine has tested the groupings and shown you the ones that matter.
Be clear about what this is: a screening signal computed on zone-typical numbers. It tells you where to look and how combinations rank, not what will be approved or what anyone will sell for. It is not a guarantee, and the developer-side tool does not contact owners — it reads public cadastre and maps the opportunity. Owner outreach, offers and negotiation are your job.
What the amalgamation engine checks and returns
The table below sets out what you feed a run against what comes back per candidate lot-group, and why each output earns its place in the decision. The figures an engine produces are indicative screening, not a valuation.
| You provide | The engine returns per lot-group | Why it matters |
|---|---|---|
| An address to scan around | Groups of adjoining / neighbouring lots | Surfaces the combinations you would otherwise have to find parcel by parcel |
| (automatic, from cadastre) | The specific lots in each group | Tells you exactly whose land the play depends on |
| (automatic) | Combined site area in m² | The consolidated footprint the yield is tested against |
| (automatic) | Units or subdivision lots the combined site screens at | The scale of the opportunity, not just that one exists |
| (automatic) | Uplift vs developing separately (e.g. "+6") | Ranks groups by how much assembly actually adds |
| (automatic) | Each lot-group mapped as a polygon | Lets you read shape, frontage and context before any outreach |
The point is easiest to see with an illustrative example — figures chosen to show the mechanic, not to appraise any real block. Take three lots of roughly 560, 580 and 600 m². Alone, each sits under the density threshold and screens at one dwelling. Combined into a single ~1,740 m² parcel they clear that threshold and can screen at around nine dwellings — an uplift of about +6 versus developing separately. Change the zone, the threshold or the grouping and the number moves; that sensitivity is exactly what a screening tool is built to run so you chase the combinations that actually pay.
One honest caveat. Every figure the engine produces — combined area, unit count and uplift — is indicative screening on zone-typical numbers. It is designed to help you spot and prioritise assembly plays fast, not to replace a planner, valuer or surveyor. Assembly also only happens if every owner agrees. Confirm controls, market evidence, title and costs before you commit.
The owner-agreement, planning and DD realities
Screening tells you a combination is worth pursuing. It does not make it happen. Three realities sit between a promising lot-group and a real site, and none of them can be skipped:
- Every owner has to agree. An assembly is only as strong as its most reluctant owner. One holdout can stall or defeat the play, and holdouts know it — which is why the premium exists and why staged options, conditional contracts and patience are the assembler's normal tools. The engine finds the group; aligning the owners is human work.
- Planning still applies in full. Clearing a minimum-lot or density threshold on paper is necessary, not sufficient. Overlays, heritage, setbacks, access, servicing and the local assessment path all still govern what actually gets approved on the combined site. Treat the screened yield as the ceiling to test, not the answer.
- Due diligence does not shrink because there are more titles. If anything it grows: multiple titles mean multiple sets of easements, encumbrances, contamination histories and boundary questions to clear. Consolidate the risk review the way you consolidate the land.
On the owner side, GoSiteHunt runs a matching service so those conversations can even start. Through /sell-together, an owner checks their address, sees the combined-site upside with their immediate neighbours screened, and registers interest. When another owner in the same run of street registers, GoSiteHunt emails both to introduce them — and that is the whole service. From there owners may list the combined opportunity on the off-market marketplace for a flat advertising fee, never a commission. GoSiteHunt never values property, never negotiates, never relays offers and never handles money. It is an advertising and introduction platform, not an agent.
Residential versus retail and mixed-use assembly
Assembly logic changes with what you are trying to build, and the engine handles both cases.
Residential assembly is usually about thresholds. You are combining modest blocks to cross the minimum lot size, frontage or density trigger that turns single-dwelling sites into a townhouse or apartment site — the A+B+C pattern above. The prize is dwelling yield and the land premium that comes with clearing the bar.
Retail and mixed-use (centre) assembly is about footprint and catchment. For centre and corridor zones the engine assembles neighbouring lots into a larger centre site — the kind that can carry a retail podium with apartments above — and catchment-tests it. Here the constraint is not just density but reaching the contiguous footprint and frontage a viable retail or mixed-use scheme needs, in a location whose catchment can support it. A single shopfront lot rarely gets there; an assembled run of them can.
In both cases the output is the same shape — the lots, the combined area, what it screens at, the uplift, and a polygon on the map — so you can compare a housing assembly and a centre assembly on the same screen and back the one with the stronger upside.
How GoSiteHunt helps
Amalgamation is one move inside GoSiteHunt's full development stack — find the parcel, run the feasibility, pin the maximum land price, reach the GO / NO-GO — available for any address across dozens of countries and free to start.
Find the combinations
Run the Amalgamations tool on the /sites screen to surface adjoining-lot groups, combined area, yield and uplift. Or scan for single parcels first with the development site finder.
Test the yield and numbers
Check what a combined site can carry with the subdivision calculator, then model the whole deal in the feasibility software.
Owner side
Own a block in a promising run? See the combined upside and get matched with neighbours via sell together, or check what your site is worth first.
Go deeper
List or find consolidated opportunities on the off-market marketplace, see the full workflow in how it works, or read more on the FAQ.
Try it on ground you know
The fastest way to understand amalgamation screening is to point it at a street you already read well. GoSiteHunt is free to start with 50 trial credits — a single-address site report costs 1 credit and an Amalgamations run costs 5, so the free tier covers several assembly scans plus a batch of individual reports before you pay anything. Run the tool on your target area, open the top-ranked lot-groups, and read their combined area, screened yield and uplift. Then do the human work: research the owners, confirm the controls, and pressure-test the numbers.
Run a free amalgamation scanSee the feasibility software
Frequently asked questions
- What is site amalgamation?
- Site amalgamation, also called land assembly, is combining two or more adjoining lots into a single larger development site. A combined parcel can clear minimum-lot-size, frontage and density thresholds that each block fails on its own, so it supports more dwellings or subdivision lots and usually attracts a land premium. It is a planning and acquisition play, not a construction one — every owner in the group has to agree before it can happen.
- How does GoSiteHunt's Amalgamations tool work?
- From the Amalgamations tool at /sites you enter an address and the engine reads the cadastre around it, then finds groups of neighbouring or adjoining lots that, combined, support a bigger scheme than each does separately. For each candidate group it returns the lots involved, the combined site area in square metres, the units or subdivision lots the combined site screens at, the uplift versus everyone developing alone, and it maps each group as a polygon. A run costs 5 credits. It is a screening signal computed on zone-typical numbers, not a guarantee, and it does not contact owners.
- How do I find adjoining development sites to combine?
- Point the Amalgamations tool at an address in the area you are targeting. It scans the surrounding cadastre and surfaces runs of adjoining lots whose combined area and frontage unlock more yield than the blocks do individually, ranked by the uplift they add. You review the mapped lot-groups, then do owner research and due diligence on the ones worth pursuing.
- Does GoSiteHunt contact or negotiate with the other owners?
- No. On the developer side the Amalgamations tool only screens the cadastre and maps candidate lot-groups — it never contacts owners. On the owner side, the separate sell-together service lets an owner register interest, and when another owner in the same run of street registers, GoSiteHunt emails both to introduce them. GoSiteHunt never values property, never negotiates, never relays offers and never handles money — it is an advertising and introduction platform, not an agent.
- Is the uplift or combined yield guaranteed?
- No. The combined area, unit or lot count and uplift are indicative screening figures computed on zone-typical numbers to help you spot and prioritise assembly opportunities fast. They are not a valuation, a planning determination, or financial or legal advice. Assembly still needs every owner to agree, and full planning assessment and due diligence still apply before anything is real.
- Can amalgamation work for retail or mixed-use sites, not just housing?
- Yes. For centre and corridor zones the engine assembles neighbouring lots into a larger centre site — the kind that can carry a retail podium with apartments above — and catchment-tests it. Residential assembly is usually about clearing density and lot-size thresholds to add dwellings; centre and mixed-use assembly is about reaching the footprint and frontage a viable retail or mixed-use scheme needs.
- How much does it cost to try?
- GoSiteHunt is free to start with 50 trial credits. A single-address site report costs 1 credit and an Amalgamations run costs 5 credits, so the free tier covers several assembly scans plus a batch of individual site reports before you pay anything. Paid products layer on only when you need them.
Screening outputs are indicative only and are not valuation, planning, financial or legal advice. Amalgamation needs every owner to agree; confirm planning controls, market evidence, title and costs before committing to a site.