Walk A Block Before You Buy

Reading the site

How to walk a block before you buy it

The land agent will show you the view. A builder walking the same block is looking at the ground, the neighbours' retaining walls, where the water sits, the power pole and the tree. Twenty minutes with a tape, a bottle of water and this list tells you more than the brochure does.

What the pro looks at first

A supervisor stands at the front boundary and looks at the ground level against the footpath, then walks to the back and looks at the fences. If the neighbour on the high side has a retaining wall and the one on the low side does not, you are about to pay for one.

Go twice, and once after rain

Walk the block in the morning and again late afternoon so you see where the sun and the shade actually land, not where the north arrow says they should. Then go back after a proper rain. Water tells the truth about a block. Puddles that sit for a day mean clay or a low point. A dark streak along the low fence means the neighbour's stormwater arrives on your side. A soggy back corner in an otherwise dry estate usually means fill over an old drainage line.

Take the contour survey if the seller has one. If they do not, take a long spirit level or a phone app and a straight bit of timber. You do not need the exact fall, you need to know if it is a few hundred millimetres or well over a metre.

Ask this

Has this block ever been filled, and can I see the compaction certificate if it has?

Read the fall from the fences

The quickest way to read a block is to look at the neighbours' fences and retaining walls. A timber fence that gets taller towards the back has a slope under it. A sleeper wall on one side at 600 high tells you the difference in level between the two blocks. Stand at the street and look down each side boundary to see whether the ground falls away from the road, towards it, or across the block from side to side.

Cross fall, side to side, is the expensive one. A block that falls front to back can often be handled with a split slab or steps at the rear. A block that falls a metre across its width needs cut on one side, fill on the other and a retaining wall on both, and the neighbour's new fence often ends up on top of your wall.

Ask this

Who is responsible for the retaining walls on each boundary, and are any already built to a standard I can build against?

The numbers
Comfortable
under 300mm across the house footprint
standard slab
Worth pricing properly
500 to 1000mm
drop edge beams, some retaining
Design for it
over 1.2 to 1.5m
split level or heavy retaining
Sleeper retaining wall height that needs engineering
commonly over 1m, lower in some councils
and approval

Where the water goes

Every block has to get its stormwater to a legal point of discharge. On a flat estate block that is the kerb at the front, easy. On a block that falls away from the road the point of discharge is often at the rear, sometimes through an easement on the neighbour's land, sometimes it does not exist yet and you pump. Look for a stormwater pit or a grated drain at the low corner. If there is nothing, ask.

Look at the street too. A kerb with a big dip at your frontage is where the road drains, and your driveway will cross it. A street tree in front of the block dictates where the crossover can go. A power pole on your frontage does the same, and both are hard to move.

Ask this

Where is the legal point of discharge for stormwater, and is it at the front or the back?

What the ground is telling you

Kick the surface. Grey or black sticky soil that holds a boot print is clay, and clay that cracks in summer and swells in winter is the stuff that moves houses. Red or sandy soil that drains fast is usually kinder. Rock showing at the surface, or the neighbour's driveway cut into stone, means excavation will be slow and the sewer trench will be dear. Look for cracks in the neighbours' render, brickwork stepping along the mortar joints, or a garden bed that has clearly been topped up more than once. Those are clues about movement.

A soil report is the only real answer, and it is worth getting before you sign or making the contract subject to it. But the walk tells you which questions to ask the geotech.

Ask this

Can the contract be subject to a soil report, and has anyone tested this block or the ones beside it?

The numbers
Class A and S
sand or rock
the easy ones
Class M
moderately reactive clay
the common assumption in base prices
Class H1 and H2
highly reactive clay
deeper beams, more steel
Class P
problem site
fill, trees, soft ground or slope

Trees, on your side and theirs

A big tree is beautiful and expensive. In both states, trees over a certain trunk size are protected and removing them needs approval you might not get. A large tree close to where the house goes also matters for the slab: roots drink from the clay on one side and the ground shrinks under that corner. Look over the fence too. A neighbour's gum tree within a house height of your boundary is your problem as much as theirs.

Measure the trunk at about chest height. It is the number the rules use.

Ask this

Are any trees on or beside the block protected, and has anyone quoted the removal or the footing changes to keep them?

The numbers
Where to measure a trunk
1m above ground
circumference, not diameter, in most rules
When to start asking
trunk circumference around 2m
thresholds vary by state and species
Root zone to think about
roughly the height of the tree
radius from the trunk

Find the pits and the pole

Walk the front boundary looking for lids: water meter, sewer inspection point, NBN pit, power pit or the nearest pole, gas if the street has it. The sewer connection point is the one that matters most. If it is at the front and you want bathrooms at the back, that is a long run under the slab. If the only sewer is on the neighbour's side or at the rear, the plumber's price changes. A pit a long way down the street means a longer trench.

While you are there, look at the crossover. If the kerb already has a cut, the estate has decided where your driveway goes. If it does not, note the tree, the pole, the pit and the neighbour's crossover, because yours cannot sit on top of any of them.

Ask this

Where exactly is the sewer connection point, and is power underground or on a pole?

What the neighbours have already built

Look at the houses either side. If they are single storey with windows facing your block, an upper floor on your side will trigger overlooking rules and might mean obscure glass or higher sills. If they have a garage on the shared boundary, you may be able to do the same on that side. If they have a two storey wall on the boundary, your side yard will be in shade most of the day.

Look at the estate signs and the covenant. Many new estates dictate roof colour, facade materials, fencing type, no sheds visible from the street, and a build-by date. None of it is in the land price and all of it is in the house price.

Ask this

Can I see the covenant or design guidelines for this estate before I sign?

Which way is the living room going to face

Stand where the back of the house would be and face the yard. If that is north or north-east, the living room and alfresco will get winter sun and the house will be easy to keep comfortable. If it is west, the afternoon sun will come straight in and you will be shading glass or living with it. If it is south, the yard will be shaded by your own house for half the year.

A block that faces the wrong way is not a deal breaker, it is a design job. But it is much cheaper to choose a plan that suits the block than to make a plan you love fight it.

Ask this

Which plan in your range has been designed for a block with this orientation?

Questions people ask

What should I check before buying a block of land?+

Fall across the block, where stormwater discharges, the soil type, trees on and beside the block, where the sewer, water and power connect, the crossover position, what the neighbours have built on their boundaries, the estate covenant, and which way the living areas will face.

How much slope on a block is too much?+

Under 300mm across the house footprint is a standard build. Between 500mm and a metre expect drop edge beams and retaining. Past about 1.2 to 1.5 metres the block wants a split level design rather than a flat slab and a lot of fill.

Can I make a land contract subject to a soil test?+

Often, yes. Ask your conveyancer to add a condition that the contract is subject to a satisfactory geotechnical report. It is a normal request and the seller's answer tells you something too.

Who pays for a retaining wall between two blocks?+

It depends on who changed the ground level and what the estate rules say. In a new estate the developer often builds boundary retaining walls before sale. Between existing owners, the person who cuts or fills usually retains their own work. Get it in writing before you sign.

Does it matter which way a block faces?+

Yes. A backyard to the north or north-east gives living areas winter sun and easy summer shade. A west facing yard means afternoon heat through the main glass. A south facing yard sits in the house's own shadow for much of the year.

Sizes quoted are typical for Australian residential work and are given to help you read drawings and ask better questions. They are not a specification. Your engineer, designer, builder and the National Construction Code decide what applies to your house.

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