Flat Roof Discussion Preparation Checklist

Photograph the whole flat roof from a window that overlooks it, taking one wide view and one along the surface at a shallow angle.

A shallow view along a flat roof reveals ripples, lifted seams and hollows that a photograph taken straight down flattens out completely.

Note whether the covering looks like one continuous surface or a set of patches, overlays and repairs added at different times.

Layers added over an original covering change what stripping involves, and they are usually visible as a change in colour or texture.

Record where the surface is blistered, split, wrinkled or lifting at an edge, describing roughly where each one sits relative to a corner or an outlet.

Do not step onto a flat roof to look more closely; access at height belongs with a qualified professional using proper equipment.

Note where moss, dirt marks or loss of the surface finish appear, and whether they follow one part of the roof rather than the whole of it.

Wear that concentrates in one area usually says something about how water sits and moves there, which is useful to whoever looks at it.

Look at the ceiling below from inside and photograph any staining, sagging, bubbling paint or discoloured plaster, noting where each sits in the room.

Marks on the ceiling below rarely sit directly under their cause, but their positions are still evidence and they are easily forgotten later.

Record when water last came in, in what kind of weather it happened and whether it stopped as soon as the rain did.

Water arriving in driving rain, after snow or long after the rain has stopped can point in quite different directions.

Look from above shortly after heavy rain and note where water is still standing, roughly how large those areas are and whether they linger.

Standing water is the single most useful thing an owner can report about a flat roof, and it can only be seen while it is there.

Note where the roof drains from, whether that is a gutter along an edge, an opening through a parapet or an outlet somewhere in the surface.

Where a flat roof discharges changes almost everything about how it has to be formed and about what happens when something blocks.

Note whether leaves, grit or moss collect around the outlet or along the gutter, and whether anything has ever been cleared from there.

A blocked outlet turns a shallow roof into a shallow tank, and owners are often unaware that anything up there needs clearing at all.

Ask what is meant to happen if the outlet blocks, and whether there is anywhere for water to escape before it backs up over the edges.

Whether anything is provided for water to escape is a question for a qualified professional, not something to read off the roof yourself.

Follow the downpipe or outlet to the ground and note where the water arrives, whether it soaks in beside a wall and whether it stands there.

What happens where roof water lands is often the reason for a damp wall, and it is far easier to observe than anything on the roof.

Record anything sitting on the surface that water has to travel around, such as a kerb, a paving slab, a pipe run or a cable tray.

Objects on a flat roof create small dams and dry shadows, and they are usually left out when the roof is described to somebody.

Photograph every point where the flat roof meets a wall of the house, including the strip of wall directly above each junction.

The junction with a wall is where flat roofs most commonly let water in, and a clear photograph of it saves a great deal of guesswork.

Note any cracked render, open joint or loose material on the wall immediately above the roof, since water reaching that face may not be coming from the roof at all.

Water entering a wall above a flat roof appears inside exactly as a roof leak does, and the distinction matters before anyone starts work.

Record any door, window or vent that sits just above the roof surface, and note how much wall there is between that opening and the covering.

How a roof meets a doorway or a window above it is a detailing matter for a qualified professional, not something to settle from a photograph.

Describe how the roof edge is finished as far as you can see it, whether that is a metal trim, an upstand kerb, a low parapet wall or a coping on top of one.

Edge treatments look minor but they set how the covering is turned and terminated, which is usually where a discussion has to start.

Note where the roof runs up to a neighbouring building, a shared wall or another roof at a different level, and consider telling the neighbour in advance.

Where a roof runs up to a neighbouring building, obligations can arise between the two owners; ask locally what your situation involves.

If a parapet surrounds the roof, note whether the coping on top looks loose, cracked or open at its joints when seen from above or from the ground.

A parapet takes weather on both faces, and what sits on top of it often matters more to the roof than the covering itself does.

Note whether the ceiling under the roof appears to sit tight against the deck or whether there is likely to be a space above it, and say how you know.

Whether a void exists above the ceiling changes the conversation entirely, and owners often have evidence for it without realising.

Look along the underside of the roof edge outside for any vents, slots or grilles, and photograph what you find at each elevation.

Ventilation openings at the edge of a flat roof are easy to see from the ground and tell a professional a great deal at a glance.

Ask where insulation sits in the present arrangement and what changing its position would involve, rather than assuming anything can simply be added.

Where insulation belongs in a flat roof, and what it does to moisture, is a matter for a suitably qualified professional in every case.

Record whether there is any hatch, panel or opening into the space above the ceiling, and photograph what can be seen from it without climbing in.

Never enter or reach into an unfamiliar roof void; ask a qualified professional what is present before anything is opened up.

Mention anything done in the room below, such as lighting set into the ceiling, an extract fan, a shower fitted underneath or a ceiling replaced.

Changes underneath a flat roof push warmth and moisture upwards in ways that are rarely connected to the roof when a problem appears.

Ask what could only be established once the covering is off, and what would happen at that moment if the deck below were found to be wet or soft.

The condition of a roof deck cannot be judged from below or from photographs and must be assessed by a qualified professional.

Decide and record whether anyone would ever need to walk on the roof, even occasionally, to clear an outlet or reach a window above it.

Roofs that get walked on are treated differently from those that do not, and the answer is far easier to give before the work than after.

Record anything standing on or fixed to the roof, such as an aerial, a dish, an outdoor unit, panels or a cable run, and note who maintains each item.

Anything standing on a flat roof usually belongs to a separate specialist; ask who disconnects it, who stores it and who puts it back.

Note any window above that opens outwards over the roof, and whether anybody leans out of it to clean, decorate or reach something.

Windows above a flat roof are the usual reason people end up standing on it, whatever anyone intended when it was built.

Consider whether you might at some point want the roof used as a terrace or a place to stand, and raise it now even if it is only a vague idea.

Whether a roof could ever be used as a terrace is a question for a suitably qualified professional and must not be assumed from its appearance.

Note who has been onto the roof in the past and what for, including anyone who has serviced equipment or cleared the outlet.

Repeated foot traffic in the same place explains a surprising amount of what a flat roof surface looks like today.

Count every opening through the surface, including a vent pipe, a flue terminal, an extract outlet, a cable entry or a bracket bolted down.

Penetrations are where the work becomes detailed, and an offer for a plain surface can look very different once they are all counted in.

Photograph any rooflight from above and below, noting whether it sits flush with the surface or is raised on a kerb around its opening.

How a rooflight meets the covering is a common source of both leaks and condensation, and the two are easily confused from inside.

Decide whether a rooflight should be added, enlarged or moved while the covering is off, since the opportunity closes when the surface is finished.

Opening a flat roof twice is a great deal more disruptive than deciding once, and this choice is regularly made too late.

Ask who deals with anything serving a flue or an appliance where it passes through the roof, and whether that is the same person doing the covering.

Anything connected to a flue or an appliance must be handled by a suitably qualified professional for that specific work.

Note anything fixed up into the roof from the room below, such as recessed lights, a track, a hoist point or a heavy fitting on the ceiling.

Fixings driven up into a roof from inside are invisible from above and occasionally explain a leak nobody can otherwise place.

Record what the room below contains and what could not be left there, including anything fixed, heavy or awkward to move at short notice.

Dust and debris fall into the room under a flat roof more readily than people expect, particularly where a ceiling is opened.

Ask whether the covering would be taken off in sections or all at once, and what the room below is exposed to at each point.

Working in sections changes how much of the roof stands open to the sky, and that shapes the risk to whatever sits underneath.

Ask how the roof is left weathertight overnight and if the weather turns, and who carries responsibility if water gets in during the work.

Who carries the risk if rain arrives while the roof is open is a point to settle in writing with the contractor before anything is stripped.

Note how materials and waste would reach and leave the roof, and whether that route passes through the house, a side passage or a neighbour's land.

Routes for materials and waste that cross somebody else's ground have to be agreed with them first, and that can take a while to arrange.

Ask what working methods are proposed on the roof and what precautions go with them, and check whether your insurer expects to be told anything.

Some flat roof methods involve heat or strong smells close to open windows, and it is far better to know before the day arrives.

Record whether anyone is at home during the day beneath the roof, and note anything they would need kept covered, protected or usable throughout.

Agree in writing what the work includes, what is expressly excluded and how anything found once the surface is off would be handled and by whom.

Flat roof disputes usually begin at the boundary between the covering and whatever lies beneath it, so define that boundary early.

Ask for photographs of the deck and the junctions while they are exposed, and keep copies of them with your property records.

That is the only moment anybody can see what the roof is made of, and those images stay useful long after the work is forgotten.

Ask what any warranty covers, who stands behind it and whether it rests on the outlets being kept clear or the surface being looked at from time to time.

A warranty on a flat roof often rests on conditions about clearing and access; ask whoever issues it to set those out in writing.

Record what you have been told about how the finished surface will shed water and where it will discharge, so it can be looked at afterwards.

Owners rarely think to look at a completed flat roof after rain, which is the one occasion it shows whether it does its job.

Write back to confirm anything agreed while looking down at the roof from a window, since that kind of conversation leaves no record of its own.

Ask what the finished roof would need looking at for, and who would be able to get to it safely in order to do that.

A flat roof needing its outlets kept clear is fine if somebody knows; it is not fine if the first sign is a stain on a ceiling.