Neither of these things will be obvious from the listing photographs. The selling information will describe both blocks in terms that make them sound equally straightforward. And the person deciding between them without a systematic way of comparing what is actually known about each site against what still needs to be investigated, is likely to be most influenced by whichever block produced the more attractive photographs or the more enthusiastic agent.

A simple site comparison framework does not replace specialist investigation. But it exposes the questions that need to be answered about each site before a decision is made and it makes it immediately visible when one block has more unanswered questions than another.

Understand What a Street Address Does and Does Not Tell You

The address and the land area in a property listing are useful starting points. They are not a site description.

An address tells you the location. It does not tell you the orientation of the block, the direction the primary outlook faces, or the solar access the site receives at different times of year. It does not tell you the slope or whether the slope runs in a direction that suits or complicates the preferred design. It does not tell you where the neighbouring buildings sit in relation to the block, or how tall they are, or where they will cast shadows in winter when the sun is lower.

The land area tells you how much ground is available. It does not tell you how much of it is buildable, how the lot coverage rules, easements, setback requirements, and any other planning or title restrictions affect what can actually be placed on the block, and where.

Even a physical visit to the site, while genuinely valuable, produces observations rather than confirmed facts. A tree near the boundary may be protected or may not. A power line running near the block may affect where structures can be built or may not. A retaining wall on the neighbouring property may affect site levels or may not. Each of these observations is a question that requires qualified investigation to answer, not a design conclusion that can be drawn from what is visible on the day.

The discipline of treating site observations as questions, rather than as conclusions, is the most useful habit a homeowner comparing blocks can develop. It keeps the site assessment honest about what is actually known and what still needs to be confirmed.

Look at the Constraints Together, Not in Isolation

Individual site constraints are often manageable. The same constraints in combination can fundamentally change what a site is suited to or what the cost of building on it will be.

A sloped block is a manageable constraint on its own. A sloped block with a narrow vehicle access point requires a different construction approach. The same block with protected trees near the buildable area, a gas easement running through the middle of the site, and a neighbouring two-storey building to the north is a block that will need careful investigation of multiple overlapping constraints before the design possibilities become clear.

The starting point for understanding constraints together rather than in isolation is a systematic record of what is visible about the site and what it implies for the questions that need to be answered. Orientation, slope, access, and the relationship to neighbouring buildings are the four most consistently significant physical site characteristics for a residential project and noting each of them in relation to the others, rather than separately, produces a more useful picture of what the site is actually like to design for.

Planning controls and title restrictions require their own investigation, separate from the physical site observations. A neighbouring property that has been developed in a particular way does not establish that the same development is permissible on your block. Different lots in the same suburb, or even in the same street, can be subject to different planning overlays, different schedule controls, different heritage considerations, and different approval histories that affect what can be approved and what conditions might apply. The only reliable way to understand the controls that apply to a specific lot is to check them for that specific lot through the relevant official channels.

Build a Comparison Sheet That Exposes Missing Information

The most useful function of a site comparison framework is not organising the information you already have. It is making visible the information you do not have, the gaps that exist for one site but not another, and the questions that remain unanswered for each block being considered.

A comparison sheet that uses the same headings for every block being evaluated does this naturally. When one block has a confirmed answer in a column and the other has a blank, the blank is the signal that something needs to be investigated before a fair comparison can be made.

Five categories of question provide a useful structure for a site comparison sheet.

What information has been verified, and by whom? For each piece of information about the site — the planning controls, the easements, the services connections, the tree protection status, the construction access arrangements, note whether it has been confirmed by a qualified investigation or whether it is an assumption based on visual observation or listing information. This distinction matters because unverified information can look the same as verified information on a comparison sheet unless the difference is explicitly recorded.

Where could construction vehicles and deliveries access the site? This is a question that is often not considered until the build is being planned, at which point the constraints on access can have significant implications for construction methodology and cost. For sites with narrow street frontages, steep driveways, or adjacent structures that limit crane or truck access, understanding the access situation during site comparison rather than during contract negotiation is considerably more useful.

What features might affect the preferred layout? The orientation of the block relative to north, the slope and its direction, the location of any trees or structures that may need to be retained or removed, the position of neighbouring buildings relative to the intended living areas, each of these can affect where on the block the dwelling can be placed and how the spaces within it can be arranged. Recording these features alongside the preferred layout allows the question of fit to be asked during site selection rather than after a purchase has been made.

Which council or specialist questions remain unanswered? Some questions about a site can be answered by reviewing publicly available information. Others require a request to the council, a search of the title and planning certificate, a geotechnical investigation, or a specific specialist assessment. For each site, the comparison sheet should list these outstanding questions explicitly, both so they can be followed up before a decision is made, and so that a site with many outstanding questions can be compared fairly with a site where more has already been confirmed.

What additional reports or investigations have been recommended? A conveyancer, a building consultant, a town planner, or a designer who has reviewed the site may have recommended specific investigations, a soil report, a heritage assessment, a drainage survey, a feature and level survey. Recording these recommendations and noting whether they have been acted on gives the comparison sheet a measure of how well-investigated each site is, independent of how the sites look side by side on paper.

If You Already Own the Site

The same framework is useful for homeowners who already own their land and are developing the brief for a custom home project. The exercise of systematically recording what is known and what is still uncertain about an owned site often surfaces constraints that were not considered when the land was purchased and identifies the points at which a preferred design element may need to be reconsidered once the site conditions are fully understood.

A desired north-facing courtyard may be constrained by an easement. A preferred garage position may conflict with the setback requirements or the slope of the land. A large glazed wall in the ideal orientation may raise questions about privacy from a neighbouring building. Identifying these tensions early before the design is fixed around them, allows the trade-offs to be considered and recorded as deliberate decisions rather than discovered as problems after the design documentation has been produced.

The record of these trade-offs is part of the design brief. When the project team understands why a particular layout decision was made, what it was trading off and why that trade-off was considered acceptable, they are better placed to raise questions if something changes that affects the basis of the original decision.

A Note on the Scope of This Article

This article describes a preparation framework for comparing sites and building a clearer picture of what is known and unknown about each one. It does not assess the suitability, the permissible development potential, or the construction cost of any particular property, all of which require current, site-specific professional advice from qualified practitioners.

For guidance on passive design considerations relevant to site selection and orientation in Australian homes, the Your Home guide on choosing and using a site is available at yourhome.gov.au. For information about planning permit requirements in Victoria, Planning Victoria publishes current guidance at planning.vic.gov.au.

EJN Build works with homeowners in South East Melbourne who are planning custom home projects. If you have questions about how to approach site analysis and site selection for a custom home, or about what questions are worth asking before committing to a particular block, we would be glad to discuss what that looks like in practice.