Viewing a home
What to check when viewing a home: 82 checks in 12 categories
Each check says how to make it in a few steps, how it is checked, and what it does not establish. Many are made with your phone; some need a tape, a question or a technician. Nesso walks you through the ones that matter to you at the viewing and keeps the record.
Walls & ceilings
Where a repair was made, where a surface is not flat, and where a crack is going. Most of it is looking at the right thing under the right light.
Side-light wall scan
- Turn the torch on.
- Hold the phone flat on the wall, lens along it.
- Walk the beam from corner to corner.
Checked with: Camera
What this does not establish: An uneven surface is an uneven surface. It says nothing about what is behind it, and a flat wall can hide as much as a wavy one.
Wall straightness
- Press the phone flat on the wall.
- Hold still for three seconds.
- Repeat low and high on the same wall.
Checked with: Phone
What this does not establish: Only as flat as the patch of wall the phone is touching. A skirting board, a picture hook or a phone case with a camera bump makes the figure meaningless, and no old building is plumb to a tenth of a degree.
Ceiling level
- Hold the phone flat on the ceiling, screen down.
- Keep still while it reads.
- Repeat at a second point, pointing the same way.
Checked with: Phone
What this does not establish: Screening, not structural work. Most ceilings you can reach are not the structure, and a reading off a door frame is a reading off a door frame.
Crack scan
- Photograph the crack square on.
- Put a coin or card in the shot.
- Note where it starts and ends.
Checked with: Camera
What this does not establish: Nesso keeps the photograph beside your own note and reads nothing out of it. Whether a crack matters is a question for someone who can see the building, not for a picture of one wall.
Crack width
- Hold a coin flat beside the crack.
- Freeze the frame.
- Tap both coin edges, then both crack sides.
Checked with: Camera
What this does not establish: A width against a household object, worked out from where your thumb landed. It is a number to compare your own next photograph to, and it is not a measurement anybody else should act on. The coin has to be flat against the wall in the same plane as the crack, or the figure is about the angle you held the phone at.
Crack tracking
- Photograph the crack from the same spot as last time.
- Use the same coin or card.
- Compare the two pictures.
Checked with: Camera
What this does not establish: Two photographs taken at different distances or under different light will look different whether or not anything moved. The comparison is yours to make, and it is only as good as the repetition.
Previous repair
- Turn the room light on.
- Photograph the whole wall.
- Look for a patch that shines or shades differently.
Checked with: Camera
What this does not establish: A repair is a repair. Most of them are ordinary maintenance, and the reason for this one is the part you cannot see.
Damp: what to look at
- Walk along the base of the outside walls.
- Look behind furniture and in corners.
- Look for stains, bubbles or peeling paint.
Checked with: Camera
What this does not establish: Visual signs consistent with damp are not a finding of damp, and Nesso will not turn them into one. Staining can be old and dry; a wall with nothing to see can still be wet.
Moisture meter reading
- Hold the meter on a suspect spot.
- Then on an inside wall.
- Compare the two readings.
Checked with: Accessory · Coming soon
What this does not establish: RICS is explicit that meter readings on building materials cannot be interpreted on their own: the same number means different things in plaster, brick and salt-contaminated render. This is a comparison, not a diagnosis.
Knock the wall
- Hold the phone a hand from the wall.
- Knock one spot with a knuckle.
- Repeat on a solid wall and compare.
Checked with: Phone
What this does not establish: A pitch and a loudness, not a material. Plaster on brick, a dry lining on battens and a stud wall can knock alike, the phone hears the room as well as the wall, and nothing here says what is inside the cavity. The count is a floor rather than a tally: the phone listens in tenth-of-a-second slices, so it hears some of your knocks and not all of them.
Windows & doors
How well they close, how much air comes past them, and how much of the street they keep out. The one part of a flat you operate a dozen times a day.
Window operation
- Open every window all the way.
- Close it again with the handle.
- Note any that stick or will not lock.
Checked with: By hand
What this does not establish: How a window behaves today. Mechanisms are adjustable and seals are replaceable, so this is a thing to raise before signing rather than a verdict on the window.
Seal: the paper test
- Close a sheet of paper in the window.
- Pull it out: top, bottom, both sides.
- Note where it slides out easily.
Checked with: By hand
What this does not establish: A comparison between four points on one window, by hand. It tells you where the sash is not pressing and nothing about the glazing itself.
Draught check
- Shut the window.
- Run the back of your hand round the frame.
- Feel for moving air.
Checked with: By hand
What this does not establish: What you could feel, on one day, at whatever the wind was doing. A still day hides a draught that a windy one makes obvious.
Air velocity at the frame
- Hold the anemometer at each edge of the shut window.
- Record the four readings.
Checked with: Accessory · Coming soon
What this does not establish: Depends entirely on the pressure difference at that moment: wind outside, a door open inside, an extractor running. Two readings minutes apart can differ for reasons that have nothing to do with the window.
Window noise reduction
- Put the phone down mid-room.
- Measure 30 s with the window open.
- Measure 30 s with it shut.
Checked with: Phone
What this does not establish: A handset microphone is not a calibrated meter and its gain is unknown, so this compares two readings taken minutes apart on the same phone. It is not comparable to any legal threshold and establishes nothing about the glazing’s specification.
Entrance door noise reduction
- Stand just inside the hall.
- Measure 30 s with the front door open.
- Measure 30 s with it shut.
Checked with: Phone
What this does not establish: Same uncalibrated handset, same caveat. It also records one moment on the landing, which may be a quiet one. It does not rate how well the door keeps noise out.
Door alignment
- Open each door halfway and let go.
- Close it slowly.
- Look along the gap, top to bottom.
Checked with: By hand
What this does not establish: A door out of square proves nothing on its own: hinges settle, frames are fitted badly, floors get relaid. It is one observation among several, not a structural finding.
Light around the entrance door
- Hall light off, landing light on.
- Shut the front door.
- Look for light round the edges.
Checked with: Camera
What this does not establish: Shows a gap, not what it costs you. A threshold gap is often a deliberate ventilation allowance rather than a fault.
Light & sun
How far daylight reaches into the room, which way the windows face, and what the sun does here across a day.
Daylight at three depths
- Turn the room lights off.
- Read at the windowsill, mid-room and back wall.
- Hold the phone flat, screen up.
Checked with: Phone
What this does not establish: Uncalibrated, and entirely dependent on the sky at that minute. A cloud passing halves it. These numbers compare three points in one room on one visit and nothing else.
How the light falls off
- Take the three daylight readings, if not done yet.
- The phone works out the rest.
Checked with: Phone
What this does not establish: Derived from the three readings above and inherits every one of their limits. It describes one line across one room at one time of day.
Which way the window faces
- Stand facing out of the window.
- Hold the phone flat.
- Keep away from the radiator.
Checked with: Phone
What this does not establish: A phone magnetometer near a steel frame, a radiator or a lift shaft can be out by tens of degrees. Take it twice from different spots, and treat a disagreement as the answer: the walk refuses a pair that disagrees rather than averaging them into a bearing.
Sun across the day
- Set which way the window faces.
- Aim at the roof edge opposite and hold still.
- Or tap Nothing opposite.
Checked with: Phone
What this does not establish: Astronomy and one angle. It knows where the sun is and how high the roof straight across stands, and works it out for a long building parallel to this window. A gap in the street, a lower roof further along, a tree or a balcony above all change it, and it cannot see them. It also inherits the bearing’s own error: a magnetometer beside a steel frame can be out by tens of degrees.
Window area against the floor
- Scan the room with the Nesso app.
- Without a scan: measure windows and floor with a tape.
Checked with: Phone
What this does not establish: Estimated by Nesso, not an official measurement. The scan measures each window’s whole opening, frame included; the rules count the part that opens, which is smaller. Where the share is what makes a room habitable, the figure that counts is the one in the planning documents.
Air & climate
Temperature, humidity, where the cold surfaces are, and whether the air in this flat actually moves.
Room temperature
- Place the thermometer away from heat and sun.
- Wait two minutes.
- Read it.
Checked with: Accessory · Coming soon
What this does not establish: One moment, and one that the person showing you the flat controlled. Handsets have no usable air-temperature sensor, so this needs an external instrument and none is connected yet.
Relative humidity
- Read the hygrometer in the main room.
- Then in the bathroom.
- Then in the furthest room.
Checked with: Accessory · Coming soon
What this does not establish: Humidity on the day you visited, after however many people have been through. It varies with weather, occupancy and whether a window was opened an hour ago.
Condensation on cold surfaces
- Take the temperature and humidity readings.
- Nesso combines them.
Checked with: Accessory · Coming soon
What this does not establish: Derived, and only as good as its three inputs, none of which is connected yet. It describes the conditions during one viewing and predicts nothing about winter.
Thermal scan
- Attach the thermal camera.
- Sweep slowly across each outside wall.
- Note where it turns cold.
Checked with: Accessory · Coming soon
What this does not establish: A thermal camera reads surface temperature and infers nothing. A cold patch has several possible explanations (a thermal bridge, air leaking past a frame, a difference in insulation) and this cannot tell them apart. It also needs a temperature difference across the wall, so in summer it shows almost nothing.
Corners, reveals and edges
- Aim the thermal camera at corners and window reveals.
- Then where wall meets ceiling.
- Note the cold spots.
Checked with: Accessory · Coming soon
What this does not establish: Same instrument, same limit: surface temperature and possible explanations, never a diagnosis. Needs a real difference between inside and outside to show anything at all.
Ventilation test
- Hold a strip of tissue on the vent grille.
- Let the bottom go.
- Watch: does it stick or fall?
Checked with: By hand
What this does not establish: A yes or no about air movement at that grille, at that moment, with the doors as they happened to be. It measures no rate and says nothing about whether the duct is clear further along.
Extractor performance
- Tissue on the extractor, fan on.
- Then fan off.
- Compare the two.
Checked with: By hand
What this does not establish: Relative, and about this grille only. Nothing here measures an extraction rate or establishes whether it meets any requirement.
Kitchen hood, and where the air goes
- Tissue on the hood, each speed.
- Look at the duct above it.
- Ask where the air goes.
Checked with: By hand
What this does not establish: The paper shows the fan is pulling. Only the answer to the question tells you where the air ends up, and that is a claim by the person answering rather than an observation.
Noise
What reaches this room, how often, and from where. The single most common reason a tenant leaves early, and the one thing no advertisement discloses.
What the room is like
- Shut the windows, switch off what hums.
- Put the phone down mid-room.
- Stay quiet for three minutes.
Checked with: Phone
What this does not establish: A handset microphone is not a calibrated meter and its gain is unknown. This figure is comparable to other rooms you measure the same way and is not comparable to any legal threshold. It records one visit, at one hour, on one day.
Peaks, not averages
- Windows shut, phone down mid-room.
- Stay quiet for two minutes.
Checked with: Phone
What this does not establish: Measures how far the loudest second rose above the rest of one uncalibrated recording. It says how far something rose, never what it was, and a loud steady room hides what a quiet one would show. How loud the moment was in the room is not measured, only how far it rose.
Low-frequency component
- Windows shut, phone down mid-room.
- Stay quiet for one minute.
Checked with: Phone
What this does not establish: Shows that low-frequency energy is present and cannot name its source. A lift motor, a heat pump, a nearby road, a metro line and a plant room in the basement all look similar from one recording; asking the neighbours is faster than guessing.
How much carries between flats
- Put the phone down in the bedroom.
- Close the door, stay quiet 30 s.
- Then listen yourself 30 s.
Checked with: Phone
What this does not establish: Measures how far the loudest second rose above the rest of thirty seconds. It does not say what made the noise (that is what your own listening is for); a loud steady room hides what a quiet one would show, and thirty seconds catches whatever happened to be happening.
Pipes
- Measure the bathroom quiet for 20 s.
- Run the tap 15 s, then shut it hard.
- Stay quiet while it listens.
Checked with: Phone
What this does not establish: Measures how far the loudest second rose above the room while you did it. It does not identify the cause (a plumber is the person who can) and a loud steady room can hide a knock the phone would otherwise have caught.
The lift
- Measure the bedroom quiet for 30 s.
- Measure again while someone uses the lift.
Checked with: Phone
What this does not establish: A few minutes on a quiet afternoon, measured as how far the loudest second rose above the room. The lift in a block of flats is busiest at the two hours you were not there, and a loud steady room hides what a quiet one would show.
Floors
Slope, local dips, how the surface behaves under a heel, and what happens at the joins.
Floor slope
- Lay the phone face up mid-room.
- Let it read.
- Turn it half a turn and read again.
Checked with: Phone
What this does not establish: A phone lying on a floor tells you about that square of floor. Old buildings are rarely level and a slope is not by itself a finding about anything.
Slope across the room
- Read at the door, the centre and the window.
- Keep the phone pointing the same way.
Checked with: Phone
What this does not establish: Three points on one line. It is a profile of the route you walked, not a survey of the floor, and it establishes nothing about what is under it. A floor that slopes evenly all the way across reads as no difference, so this cannot tell you the floor is level.
Local dip
- Pick the spot where the slope changed.
- Read at four corners of a metre square.
Checked with: Phone
What this does not establish: Four readings around one point. It locates something to ask about; it does not say what is beneath the floor covering.
Heel drop
- Walk across the room, heel down firmly.
- Feel for bounce or give.
- Try near the walls and in the middle.
Checked with: By hand
What this does not establish: A subjective impression of stiffness. It is not a measurement of what the floor will carry, and nothing about load-bearing capacity can be concluded from it.
Transitions
- Find every join between floor coverings.
- Run your foot across it.
- Note any step, gap or lift.
Checked with: By hand
What this does not establish: Describes the join. It does not tell you whether the covering, the screed or the floor underneath is the reason for it.
The note a tile makes
- Ask if you may tap the tiles.
- Tap across them with a knuckle.
- Listen for a patch that answers differently.
Checked with: By hand
What this does not establish: A different note is not a loose tile. Substrate, adhesive coverage and what is beneath the floor all change it, and the only thing it establishes is where to ask.
Water & plumbing
Pressure, drainage, seals and the cupboard under the sink. Five minutes here answers questions that take months to surface otherwise.
Pressure with two taps running
- Open the kitchen tap fully.
- Turn the shower on too.
- Watch the kitchen flow.
Checked with: By hand
What this does not establish: What you saw, at whatever pressure the building had at that hour. Mains pressure varies through the day and between floors.
How much water the tap gives
- Hold a bottle under the tap.
- Open the tap fully and time the fill.
- Pick the bottle size.
Checked with: Phone
What this does not establish: One tap, at whatever pressure the building had at that hour, timed by hand. It does not separate a restricted aerator from low mains pressure, and it says nothing about the shower unless you measured the shower.
Drainage
- Fill the basin a few centimetres.
- Start the timer and pull the plug.
- Stop when the water is gone.
Checked with: Phone
What this does not establish: One test on one day. A slow drain has several ordinary causes and this does not separate them.
Cistern refill
- Flush and start the timer.
- Stop when the filling stops.
- Listen 30 s for running water.
Checked with: Phone
What this does not establish: Tells you the valve is passing water. Which part, and what it takes to fix, is a plumber’s question.
Under the sink
- Open the cupboard under each sink.
- Torch on, look at every joint.
- Run a finger along each one.
Checked with: By hand
What this does not establish: Finds evidence of water having been there. It does not tell you whether it is still leaking, or how long ago it was.
Shower and bath seals
- Look along every silicone line.
- Press gently at the corners.
- Note gaps, black or soft spots.
Checked with: By hand
What this does not establish: The state of a bead of silicone. Whether water has been getting past it is not visible from this side.
Bathroom: what to look at
- Photograph the ceiling, shower wall and corner above the door.
- Look for stains, peeling or fresh paint.
Checked with: Camera
What this does not establish: Visual signs consistent with damp are not a finding of damp, and Nesso reads nothing out of the photograph. It keeps the picture beside your own note.
Heating
Whether it comes on, how fast the room follows, and how the heat is distributed across a radiator.
Does each radiator come on
- Ask for the heating on.
- Wait ten minutes.
- Feel top and bottom of each radiator.
Checked with: By hand
What this does not establish: One radiator on one afternoon. It says nothing about the boiler, the system pressure, or what the flat costs to heat in January.
How fast the room follows
- Read the temperature when the heating starts.
- Again at 10 and 20 minutes.
Checked with: Accessory · Coming soon
What this does not establish: Depends on the starting temperature, the outside temperature, and whether a window was open an hour before. Needs an external thermometer, and none is connected yet.
Heat across a radiator
- Wait ten minutes after the heating starts.
- Photograph each radiator with the thermal camera.
Checked with: Accessory · Coming soon
What this does not establish: Surface temperature of a radiator. It is a reason to ask about the system, not a finding about it.
Electrical
What a socket tester reads, whether every switch does something, and what the consumer unit looks like from outside. Nothing here is opened.
Socket tester
- Plug the tester into each socket.
- Start with kitchen and bathroom.
- Photograph the lights.
Checked with: By hand
What this does not establish: A three-light tester checks a handful of faults at one outlet and misses several that matter more, including a high-resistance earth and a wrongly shared neutral. It cannot establish that an installation meets any standard, and a pattern it does not expect needs a qualified electrician rather than a second opinion from you.
Every switch
- Press every switch in the flat.
- Note the ones that do nothing.
Checked with: By hand
What this does not establish: Records which switches did something. It says nothing about the wiring behind any of them.
The consumer unit, from outside
- Find the fuse box. Do not open it.
- Photograph it closed.
- Look for scorch marks or missing covers.
Checked with: Camera
What this does not establish: The outside of a closed box. Nesso reads nothing out of the photograph. Nothing about the condition of an electrical installation can be established this way; that is an electrician’s job with an instrument, and it is the one thing in this whole check that should not be improvised.
Space & measurements
Room dimensions, ceiling height, and the gap between the square metres advertised and the square metres you can walk on.
Room dimensions
- Walk the phone round the room at waist height.
- Press Done.
- No scan? Measure the two longest walls.
Checked with: Phone
What this does not establish: Estimated by Nesso, not an official measurement. Depth scanning is out by centimetres at best, worse on dark or glossy surfaces, and no part of it is a cadastral figure.
Ceiling height
- Scan the room, or use your earlier scan.
- No scan? Measure it with a tape.
Checked with: Phone
What this does not establish: Estimated by Nesso, not an official measurement. Where a height requirement is what makes a room habitable, the figure that counts is the surveyed one in the planning documents.
Area you can walk on
- Scan every room.
- The phone adds them up.
Checked with: Phone
What this does not establish: Estimated by Nesso, not an official measurement, and it excludes anything you did not scan (cupboards, the balcony, the cellar). Every error in the room scans adds up here.
Advertised against measured
- Type the area in the advert.
- Nesso sets it beside what you scanned.
Checked with: Phone
What this does not establish: A difference between an estimate and a claim, and it is not evidence that anyone misrepresented anything. Listings quote several different areas: in Italy *superficie commerciale* legitimately includes walls, balconies at a fraction, and cellar space you cannot stand in, and in Denmark *boligareal* and the built area are different figures. Ask which figure was used.
Door widths
- Scan the room, or use your earlier scan.
- No scan? Measure the narrowest doors.
Checked with: Phone
What this does not establish: Estimated by Nesso, out by a centimetre or two. The scan measures the opening in the frame; with the door open, the leaf and the hinges take a few centimetres of it.
Height above the street
- Read at the street door.
- Walk up with this screen open.
- Read again at the flat door.
Checked with: Phone
What this does not establish: Two readings of the air pressure, not a survey. The weather and a draught in the stairwell move it too, so it is good to about a metre over a few minutes and worse over a longer walk. The floor is a range, because storeys run from under three metres to nearly four.
Signal & connection
What the phone reaches from each room, and what your own operator does here. The question somebody working from the back bedroom asks first and no advertisement answers.
What the phone reaches, room by room
- Stand where you would work.
- Measure.
- Move to a second spot and measure again.
Checked with: Phone
What this does not establish: What this handset, on whatever it is connected to, reached this afternoon. It is not a signal strength, it is not your own operator, and it is not what a contract in this building would give you. A room nothing got through from is a finding worth writing down; one spot on its own is not worth much.
Ask, don’t measure
The questions that beat any instrument, and the ones a twenty-minute viewing cannot settle at all. Nesso deliberately builds no feature for these.
Why was this repaired?
- Stand at the fresh paint or plaster.
- Ask why it was repaired.
Checked with: By hand
What this does not establish: An answer from an interested party, recorded as an answer rather than as a fact.
When were the windows replaced?
- Ask when the windows were replaced.
- Ask if all of them were.
Checked with: By hand
What this does not establish: A date given from memory. Ask whether there is an invoice if it matters.
How old is the boiler?
- Ask when the boiler was installed.
- Ask to see the service book.
Checked with: By hand
What this does not establish: A date and a book. It says nothing about the condition of the appliance, which is a termotecnico’s question.
Ask for twelve months of bills
- Ask for twelve months of energy bills.
- Ask for the building’s charges statement.
Checked with: By hand
What this does not establish: Somebody else’s twelve months, at their thermostat setting and their occupancy. Yours will differ, but the January figure still tells you what the building is like.
What the building has had done
- Ask what major work was done in ten years.
- Roof, façade, lifts, pipes, heating.
Checked with: By hand
What this does not establish: A summary from memory. The verbali of the assemblea are where it is written down.
What the building is about to spend
- Ask what works are voted or planned.
- Ask for the last two assembly minutes.
Checked with: By hand
What this does not establish: Only as complete as the answer. The minutes are the record, and a buyer should read them rather than take a summary.
Ask a neighbour
- If you meet a neighbour, ask one question:
- What is it like to live here, at night too?
Checked with: By hand
What this does not establish: One person’s experience, and they may have a reason of their own. Recorded as what they said.
Come back at a different hour
- Ask for a second visit after 20:00.
- Or on a weekday.
Checked with: By hand
What this does not establish: Two visits are two moments, not a pattern. They are still twice as many as most people manage.
Walk the street in the evening
- Come back after dark.
- Walk the block.
- Note light, people, parking.
Checked with: By hand
What this does not establish: One evening. It is your own observation of what was there, and Nesso keeps it as that, never as a judgement about the area or the people in it.
Mobile signal, room by room
- Walk into each room.
- Look at the bars on your phone.
- Bedroom and bathroom first.
Checked with: By hand
What this does not establish: Your network, your handset, that afternoon. Another operator may be entirely different in the same room.
Look out of every window
- Look out of each window.
- Up, down and across.
- Note what is there.
Checked with: By hand
What this does not establish: What is there today. A cleared site opposite is a building in two years.
Smell, with the windows shut
- Ask for the windows shut a few minutes.
- Stop in kitchen, bathroom, bedroom.
- Smell.
Checked with: By hand
What this does not establish: A subjective impression. It tells you where to look, and it establishes nothing on its own.
Smell, with the windows open
- Open the windows.
- Stand there for a minute.
- Smell.
Checked with: By hand
What this does not establish: One minute, one wind direction, one time of day.
Stand still and listen
- Stand mid-room.
- Stay silent for one minute.
- Listen.
Checked with: By hand
What this does not establish: A minute of one afternoon. It is the cheapest minute in the whole list and it costs nothing to repeat.
The ceiling under a roof or terrace
- Top floor or terrace above? Look up.
- Check the ceiling and its corners.
Checked with: By hand
What this does not establish: A dry ceiling on a dry week says less than it looks like it does. What was repainted last month says less still.
The cellar and the garage
- Ask to see the cellar and garage.
- Smell the air.
- Look for a tide mark on the walls.
Checked with: By hand
What this does not establish: A cellar is expected to be cooler and damper than a flat. What matters is the evidence of standing water, not the humidity itself.
Previous water damage
- Ask: was there ever a leak?
- Ask: was it claimed on insurance?
Checked with: By hand
What this does not establish: An answer, recorded as an answer. The insurance record is where it is verifiable.
Disputes and planned works in the condominio
- Ask for the last two assembly minutes.
- Ask about any lawsuits or arrears.
Checked with: Technician · Coming soon
What this does not establish: Not a physical check and not one this app performs. Nesso records that you asked and what came back; reading the documents is an avvocato’s or a commercialista’s work.
How old the building is
- Look at the front and the stairwell.
- Ask the year it was built.
Checked with: By hand
What this does not establish: A reading of a front, not a date. Fronts are redone and flats renovated. The year of construction is on the APE and in the building’s permits, and what the structure is made of is a technician’s question.