When people start planning a granny flat, it’s natural to focus on the building itself.
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How many bedrooms can we fit? How large should the kitchen be? Where will the bathroom go? Should the living area open onto a deck?
They’re all important questions. But there’s another decision that can have just as much influence on the finished project: exactly where the granny flat sits on the property.
Move the same building a few metres, rotate it 90 degrees or change which direction the living areas face, and you can end up with a very different home.
Good site planning can improve natural light, privacy, access and outdoor space. It can make construction simpler and help the new dwelling sit comfortably alongside the existing house.
Poor site planning can do the opposite.
That’s why we believe a granny flat should never be designed in isolation from the land it’s going to sit on.
A Floor Plan Isn’t a Site Plan
It’s easy to find a floor plan you like and imagine it sitting neatly in the backyard.
The problem is that a floor plan only tells you what’s happening inside the building.
It doesn’t tell you what the bedroom window will look at. It doesn’t show how somebody gets from the street to the front door. It doesn’t tell you whether the afternoon sun will hit a large expanse of glass, whether the living room will overlook a fence or whether the new dwelling will dominate the main home’s outdoor area.
These things only become apparent when the building is considered in the context of the actual property.
This is also why two homeowners choosing exactly the same granny flat design could end up with very different results.
The building might be identical.
The sites aren’t.
Start by Understanding the Entire Property
Before deciding where a granny flat should go, we want to understand what we’re working with.
That means looking beyond the dimensions of the available backyard.
Where does the existing home sit? Where are its main windows and outdoor living areas? Which parts of the backyard are actually used? Where do people currently enter and leave the property? Is the land flat or sloping? Are there established trees, sheds, pools or retaining walls?
Then there are less visible considerations.
Drainage, underground services and other site constraints can all influence what is practical. Access for construction also matters, particularly on established properties where the main house occupies a significant portion of the block.
Looking at these things early allows the design to respond to the property rather than trying to force a predetermined building onto it.
Don’t Automatically Push the Building Into the Back Corner
One of the most common assumptions is that a granny flat belongs as far into the backyard as possible.
Sometimes that’s exactly where it should go.
But not always.
Pushing the building against the rear of the property can create a long access path, leave an awkward strip of unused land or position living areas against a boundary where there isn’t much of an outlook.
In other situations, placing the building slightly differently could create two much more useful outdoor areas – one belonging naturally to the main house and another associated with the granny flat.
That’s why we prefer to think about the entire backyard rather than simply asking, “Where can we fit the building?”
A few metres can make a surprising difference.
Orientation Can Change How the Home Feels
Orientation is particularly important in a compact home because every room has to work hard.
A well-positioned living area with good natural light and a pleasant outlook can make a relatively small space feel open and comfortable. The same room facing a dark side boundary can feel much more enclosed.
This doesn’t mean every site has one perfect orientation. Existing homes, neighbouring properties, access requirements and the shape of the block all create constraints.
The job is to find the best balance.
We might, for example, have an opportunity to position the main living area toward a garden while placing bathrooms, laundries or storage areas on the less desirable side of the building.
Windows can then be considered as part of the site planning rather than simply placed symmetrically on the elevations.
Where does the morning light come from? What will you actually see through the kitchen window? Can a bedroom receive natural light without looking directly toward the main house?
These decisions don’t necessarily add significant cost to a project.
They simply require thought before construction begins.
Privacy Is About More Than Distance
Homeowners sometimes assume that putting as much distance as possible between the main house and granny flat will automatically create privacy.
Distance helps, but orientation is often more important.
Imagine two dwellings separated by a reasonable section of garden but with their main living room windows facing directly toward each other. Both occupants may feel as though they’re constantly on display.
Now imagine the same buildings positioned so their primary living spaces face different parts of the property.
The physical distance hasn’t changed, but the relationship between the two homes has.
The same principle applies to entrances.
If the granny flat’s front door opens directly toward the main home’s patio, every arrival can feel like an interruption. A small change in orientation, combined with a path and some landscaping, might create a much greater sense of independence.
Experienced granny flat builders should therefore be considering sightlines and how people will move around the property – not just whether the proposed dwelling fits within the available building area.
Give Both Homes Useful Outdoor Space
One of the risks when adding another dwelling is treating the backyard as space that can simply be consumed by the new building.
But outdoor space still matters after construction.
We generally want to avoid creating leftover areas that technically count as open space but aren’t particularly useful.
A narrow strip behind a building, for example, might add square metres on a plan without providing somewhere anybody would actually want to sit.
It can be better to consolidate the available outdoor area into spaces with a clear purpose.
Perhaps the existing home retains its entertaining area and lawn, while the granny flat gets a smaller private courtyard connected directly to its living room.
The important word is private.
Even a relatively compact outdoor area can feel valuable if it has good sunlight, a pleasant outlook and some separation from the main dwelling.
Access Should Feel Intentional
A granny flat can be beautifully designed internally and still feel compromised if getting to it means walking past bins, squeezing between a fence and an air-conditioning unit, or crossing directly through the main family’s entertaining area.
We try to imagine the completed property from the occupant’s perspective.
You arrive home carrying groceries. Where do you park? How do you get to the front door? Is the path obvious? Is there lighting? What happens when it’s raining?
For family accommodation, you may not need complete separation. But even when parents, grandparents or adult children are living on the same property, a clearly defined entrance helps the granny flat feel like a home of its own.
Access also needs to work during construction.
A tight side passage doesn’t necessarily prevent a project from proceeding, but it can affect how materials and equipment reach the building area. Identifying those constraints early means they can be incorporated into the construction strategy rather than becoming an unpleasant surprise once work begins.
Look Below Ground as Well as Above It
Some of the most important parts of site planning aren’t visible when you walk around the backyard.
A new dwelling needs services.
Where those services are located – and how easily they can reach the proposed building – can influence both the design and the cost of construction.
Drainage is particularly important because water has to go somewhere. Existing ground levels, stormwater management and the location of relevant infrastructure can all influence what is practical.
This is where early investigation pays for itself.
Moving a building on a concept plan is easy.
Discovering after detailed design that its position creates unnecessary servicing or drainage complications is considerably less convenient.
Sloping Sites Need More Thought, Not Necessarily a Worse Design
A slope is often viewed immediately as a disadvantage.
It can certainly introduce additional considerations, but the important thing is understanding the site early enough to design for it.
Trying to impose a solution intended for perfectly flat land onto a sloping backyard can result in extensive earthworks, retaining requirements or awkward changes in level.
Sometimes a design that responds to the existing contours makes more sense.
The same applies to the relationship between the granny flat and the main house. On some sites, changes in elevation can actually help create separation and privacy.
The objective shouldn’t automatically be to make every property behave like a flat, empty block.
It’s to develop a design that makes sense for the land that’s actually there.
Think About What the Property Will Feel Like Afterwards
This is one of the questions we think homeowners should ask more often.
Don’t just picture the granny flat.
Picture the whole property once the project is finished.
Stand at the main home’s kitchen window. What will you see?
Sit in the existing outdoor entertaining area. Does it still feel open and private?
Imagine walking from the street to the new dwelling at night. Does the route make sense?
Now stand inside the proposed granny flat. What does its living room look towards? Does it have somewhere pleasant to sit outside? Does it feel like a genuine home or like a building that has been fitted into whatever space happened to remain?
These simple thought exercises can reveal problems that aren’t obvious when you’re concentrating entirely on dimensions and floor plans.
Sometimes the Best Site Plan Requires a Compromise
Every site has constraints.
You might have an ideal location for natural light that creates difficult access. Another position might provide excellent privacy but require a longer service run. Maximising the size of the granny flat might reduce the quality of the outdoor areas.
Good site planning is rarely about finding an option with no disadvantages.
It’s about deciding which compromises matter least.
This is where experience becomes valuable. A homeowner may understandably focus on gaining another metre in a bedroom, while someone who has worked through many similar projects might recognise that moving the entire building slightly could improve access, privacy and the outlook from the living area.
The best solution on paper isn’t always the one with the largest floor area.
It’s the one that works best when people actually live there.
Plan the Site Before Perfecting the Building
There is nothing wrong with looking at floor plans early in the process. They’re useful for understanding how much space you need and how different layouts might work.
Just don’t fall in love with one before you’ve properly considered the site.
Start with the property.
Understand the available space, orientation, access, existing structures, services, levels, privacy and the relationship with the main house. Then use that information to determine where the granny flat should sit and how its layout should respond.
It’s much easier to make these decisions while everything exists as lines on a drawing.
Once concrete has been poured and walls are going up, opportunities disappear quickly.
A successful granny flat project isn’t simply about creating a good small home.
It’s about creating the right small home, in the right position, for that particular property.
