Outdoor Level and Slope Questions Checklist

Stand at the top and the bottom of the garden and describe the fall in plain terms: gentle, noticeable, or genuinely hard work with a loaded barrow.

A consistent everyday description travels better between owner and professional than a guessed figure that later turns out to be wrong.

Note whether the ground falls away from the house, towards it, or across the plot from one side to the other.

Direction of fall governs almost every later decision, from where water ends up to whether a level terrace has to be built up or cut in.

How a fall should be handled, and what it means for water and for structures, is a matter for a qualified professional.

Walk the garden with a long straight edge or a taut line and note where the ground dips or humps unexpectedly along it.

Eyes smooth out irregularities that matter, and a taut line makes local hollows obvious without any specialist equipment.

Record where the slope changes suddenly rather than running evenly, since a break of slope often marks something buried or previously built.

Abrupt changes frequently indicate old walls, filled ground or a former terrace, all of which affect what can be done there.

Identify which parts of the garden feel level underfoot but are not, such as a lawn that has slowly crept downhill over the years.

Apparently level ground that is not is the source of many disappointed expectations about where a table or a building could sit.

Write down where you have to brace yourself, push harder with a mower, or put a wedge under a chair leg to sit comfortably.

Physical effort is a reliable owner-side proxy for gradient and marks precisely the places a design needs to address.

Note how far below the back door threshold the ground currently sits, describing it by comparison with a familiar object rather than guessing a figure.

A comparison such as roughly a brick course or roughly a step down carries the meaning without pretending to a precision you do not have.

Ground levels against a building can affect damp protection and must be determined by a qualified professional rather than assumed by an owner.

Check whether any airbrick, vent or damp course line is visible along the base of the wall, and photograph each one you find.

These features constrain what a new surface can do at the house edge, and they are frequently buried by well-meaning landscaping.

Ask a qualified professional what any vent or damp course at your property requires before a surface level near the house is discussed.

Record whether soil or a raised bed already sits against the house wall, and note roughly how long it has been there if you know.

Existing soil against a wall is a common inherited condition and is exactly the sort of thing that should be raised early, not discovered late.

Note where rainwater goes once it leaves the roof, and whether it travels towards the walls or away from them.

The relationship between roof water and ground level at the house is a question a professional will ask almost immediately.

Write down which external doors open outwards and how much clear room they need to swing over any new surface.

An outward-opening door restricts what can happen at threshold level, and it is easy to overlook when reading a plan.

Look at whether the house sits on a plinth, behind a step, or flush with the surrounding ground on each side of the building.

The relationship differs around a single house, and recording each side prevents an assumption made at the back being applied at the side.

Count the places where somebody changes level between the back door and the far end of the garden, including single awkward steps.

Isolated single steps cause more difficulty than flights, and they tend to be omitted when owners describe a garden from memory.

Note any step that is a different height from the one beside it, since inconsistent risers are commonly reported as a source of stumbles.

Recording the inconsistency is useful evidence for a designer, even though the remedy is not something to settle yourself.

Step geometry, handrails and edge protection outside are matters for a qualified professional working to the relevant local requirements.

Record which routes get used while carrying something bulky, and whether the person can see their own feet on the way down.

Sightlines while carrying are a practical constraint that rarely appears in a brief but strongly affects where steps should sit.

Check whether a wheelbarrow, mower, pushchair or wheelchair currently has any route at all between the different levels.

If no wheeled route exists today, everything from upkeep to material delivery is affected, and that deserves stating explicitly.

Write down where somebody in the household would want something to hold on to, without deciding what that should be.

Identifying the need is the owner's knowledge; specifying the response belongs with a professional who can assess the situation.

Identify which steps become slippery in wet or frosty conditions and which of them sit permanently in shade.

Shaded steps stay wet far longer, and knowing which ones matters for both position and material discussions.

Walk the boundary and the garden and note anywhere soil on one side sits visibly higher than the other, whatever is holding it in place.

Retaining elements are often disguised as fences, kerbs, sleepers or planted banks and go unrecognised until work is proposed nearby.

Anything holding back ground is a structural matter; ask a qualified professional to assess it rather than judging from the surface.

Photograph every wall, sleeper edge, kerb or bank that appears to be doing retaining work, including any cracks, bulges or open joints.

Dated photographs let somebody judge later whether a bank has carried on moving, which a single visit can never establish.

Note whether an existing retaining element shows any sign of drainage behind it, such as weep holes or a gravel line at the base.

The presence or absence of drainage is a question a professional will want answered, and the surface evidence is visible to an owner.

Drainage behind a retaining structure is a design matter for a qualified professional; never assume an existing arrangement is adequate.

Record whether any retaining feature has moved, leaned or shed material during the time you have lived at the property.

Change over time is information no survey can recover, and it is precisely what a professional will ask the owner about.

Note what sits above and behind any retained bank, including a shed, a parked vehicle, a mature tree or a neighbouring surface.

What loads a bank matters as much as its height, and it is exactly the sort of detail an owner can record before any assessment.

Write down whether any part of the slope has slumped, washed out or needed making good before now.

Repeated repair in one place usually points at an underlying cause that a cosmetic fix will not address.

Consider whether creating a level area would mean cutting into the slope, building it up, or some combination of the two.

Cutting and filling have quite different implications for retaining, drainage and neighbouring levels, so it helps to have thought about which you are asking for.

Work out where excavated soil could be stored on the plot, and whether that spot happens to be somewhere you also want to use.

Spoil takes up far more space loose than it did in the ground, and nowhere to put it is a genuine constraint on how work proceeds.

Write down whether the plot has any route capable of taking material away, or whether everything would have to be barrowed out by hand.

Whether spoil can leave by machine or only by hand changes what is practical on a sloping site more than the gradient itself does.

Record any filling you know about on the plot, since fill frequently behaves quite differently from undisturbed ground.

Previously filled ground is common in gardens and affects what can sensibly be built above it.

Made ground and imported fill affect what may be built on them and must be assessed by a qualified professional.

Note whether tree roots are likely to be present where ground would be cut away or raised, based on what you can see at the surface.

Root spread usually extends well beyond the canopy, and flagging it early avoids a design that cannot be built without harming a tree.

Ask a qualified arboricultural professional what a tree here needs before ground near it is cut away or raised, and confirm locally what applies.

Consider whether a level change could push water or soil towards a neighbour, and note where the ground falls at that edge.

Level changes near a boundary raise questions that go beyond construction, and they are much easier to address before a design is committed.

Note where your ground level sits relative to each neighbouring garden along every part of the boundary.

Relative level determines where water goes and which side any retaining element is working for, both of which matter early.

Record whether a neighbouring surface, drive or patio sits above your plot at any point along the line.

Ground held up on the neighbouring side changes what can be excavated close to the boundary.

Changes affecting a neighbouring level or a shared structure are legal as well as technical; take suitably qualified advice before planning them.

Write down whether an existing boundary wall also appears to be retaining ground for one side rather than simply dividing the plots.

A wall doing two jobs is treated very differently from one that only marks a line, and the distinction should be established early.

Note where a fence post base is exposed by a level difference, which often signals soil moving or washing away over time.

Exposed bases are a visible symptom of a slow process, and dating them roughly helps a professional judge whether it is continuing.

Consider whether raising your ground level would increase how much you see into a neighbouring garden or window.

Overlooking created by a raised surface is a common source of objection and is far better anticipated than discovered.

Record what you already know about who owns each boundary feature that sits on a change of level, and how you know it.

Distinguishing what you have been told from what is documented saves a great deal of confusion later.

Mark on a sketch the largest genuinely flat area you have now, and note whether it happens to be where you would want to sit.

Existing flat ground is the easiest flat ground to work with, and testing whether it suits your intended use is a useful reality check.

Look at whether a table and chairs currently rock where you place them, and where somebody has wedged something under a leg.

Wedges are an honest record of where the ground is not as flat as everyone assumes it is.

Consider how much of the garden you would accept giving over to steps or a bank in order to gain one properly level terrace.

Level areas on a slope are paid for in the space taken by whatever supports them, and knowing your tolerance shapes the design.

Write down whether a sloping lawn is actually usable for the activities you have in mind, or whether it only works to look at.

Play, seating and drying laundry all need something close to level, while a slope can be perfectly good as planted ground.

Think about where a new level change or raised area would block a view you currently value from inside the house.

Terraces and banks change the outlook from indoors, which is where most people see the garden from most of the time.

Record which flat areas are already dry underfoot and which sit at the bottom of the fall collecting whatever runs down.

Flat and wet is a different proposition from flat and dry, and the distinction matters when choosing where to concentrate use.