AP Flood Consultancy is an independent roofing and waterproofing consultancy, based in Ampthill, Bedfordshire and working across the UK. Several thousand roofs between us — enough to know which details fail, which products fail, and which ones were never going to work.
The question underneath is always the same: what happened, how bad is it, and who carries it. What changes is what you need the answer for.
A leak in a building you handed over, or a subcontractor’s work you’re being asked to stand behind. We establish the cause quickly and record it so it survives the conversation that follows. We’re instructed by main contractors at least as often as against them.
Typically: defect investigation · causation opinion · remedial scope · pre-cover QA & handover evidence
Condition, priority and urgency across a portfolio — a schedule a board can act on, not a list of things a roofer noticed while he was up there. And on every defect, the question that decides who carries it: workmanship, product, design or fair wear.
Typically: condition & lifecycle surveys · PPM regimes · warranty inspection · support to a warranty claim · remedial specification
Independent testing before the membrane is covered, with every breach plotted, repaired and re-tested. When a leak appears two years later and the finger points at you, that record is the difference between an argument and a closed conversation. A manufacturer’s rep is not independent evidence.
Typically: pre-cover electronic leak detection · handover evidence pack · diagnosis on inherited work · second opinion when workmanship is challenged
Specialist input on building surveys, due diligence and dilapidations where a roof or deck sits beyond your own competence. Instructed by you, written to your evidential standard, and reported so it goes into your document without being rewritten.
Typically: technical due diligence · specialist inspection · dilapidations input · second opinion
Independent technical evidence on defect, causation and remedial scope, prepared to be disclosed and relied on. If the evidence doesn’t support the case, we’ll tell you before you spend money finding out.
Typically: preliminary opinion · technical evidence · causation & scope · support to the appointed expert
Water gets into buildings predictably — a detail missed on a drawing, a defect built in and covered over, a leak years later, an argument about who pays. We work at all four points, and the forensic work is exactly what makes the preventative work worth buying. We know what fails because we spend our lives finding out.
Independent QA on new waterproofing, and the inspection regime that keeps a warranty alive afterwards.
Finding the actual source of a leak rather than the nearest plausible suspect.
Turning a defect into a decision: what needs doing, to what standard, and in what order.
Turning findings into evidence that holds up in negotiation, adjudication or court.
Before the membrane is covered, a defect costs what the repair costs. Once the green roof or the paving deck is on top of it, it costs the repair and everything above it. After handover, it costs a conversation with a solicitor. The work is identical on all three days. Only the price changes.
Three people have money on that single day. The principal contractor, about to transfer a risk they cannot see. The roofing contractor, whose workmanship is about to disappear under something heavy along with any ability to prove it was right. And whoever takes the building on, who inherits it with no idea what they have got.
One attendance, one record, three different fears answered. It is also the point at which the long record starts — the thing that makes a warranty claim provable at year eight rather than arguable.
A roof failed. It had been under a regular inspection regime for years, and the first question we were asked was how it had been missed.
We read the inspection reports before we went near the building. They had been produced by a cleaning company.
On the first visit the defects were obvious — the kind you see from the hatch, not the kind you find with equipment. None of it was hidden. It had simply never been looked at by anyone who would recognise what they were seeing.
An inspection regime is only worth the competence of whoever carries it out.
Most people offering an opinion on your waterproofing also install it, supply it, or are approved by whoever does. That is a difficult position from which to write down that something has failed.
AP Flood has no installation arm, no manufacturer approval to protect and no product to specify. We are paid to reach a conclusion, not to reach a particular one. It is the reason our reports are accepted by the people who are going to be asked to pay for the remedy.
We work to the principles of the RAWTA code of practice for independent third-party test houses — no ownership of, or allegiance to, waterproofing manufacturers, suppliers or contracting businesses, and an obligation to tell you the limitations of a method before we start rather than after.
Independence is only worth what it costs. We decline instructions where the evidence will not support the case we are being asked to make — and we would rather say so in the first week than in the sixth month.
The rep who signs off the installation works for the company that sold the membrane. That isn’t a criticism. It just isn’t independent.
On site, it is one of two people. You will know before we arrive which of us is coming, and you will get the same people back the next time you call. On an investigation or an expert instruction, that is our lead consultant.
Twelve disciplines — from electronic leak detection on a podium deck before it’s covered, to a forensic investigation on a flat roof that’s been leaking for twenty years.
Low-voltage and high-voltage integrity testing to locate breaches in the membrane before it is covered. Carried out to the RAWTA code of practice, and to LRWA GN18:2025 on liquid applied membranes, with every breach plotted and re-tested after repair. It is the core of the handover evidence pack.
Independent inspection of new membrane installation — laps, terminations, upstands, penetrations and detailing — against the system manufacturer's requirements and the design intent.
Scheduled inspection regimes to BS 6229:2025 that keep a manufacturer or latent defects warranty valid, with the documented record the policy requires. Every visit records falls and drainage performance where they can be observed, not just the state of the membrane.
Systematic diagnosis of water ingress — establishing path, source and cause rather than treating the point of appearance. Includes flood testing and staged elimination.
Non-destructive survey of moisture distribution within a roof build-up, so you replace the wet area and only the wet area — and can prove where the boundary was.
Assessment of remaining service life, defect schedules and prioritised remedial options — including falls, ponding and drainage where they can be observed. Written so a finance director can act on it, not just a roofer.
Specialist envelope input to pre-acquisition and pre-disposal reporting: what condition the roofs and decks are actually in, what is likely to fall due within the holding period, and what scope of work it will take to deal with it.
Defining the repair properly before it is priced — scope, system, detailing and standard of workmanship — so tenders are comparable and the contractor cannot later say the scope was unclear. We write the specification; the market prices it.
Review of waterproofing details before they are built — junctions, upstand heights, terminations and interfaces with other trades. The cheapest place to fix a detail is on the drawing.
Independent technical evidence on defects, causation and remedial scope for negotiation, adjudication and mediation — and to support the legal team where a matter goes further.
IPAF-certified operators, and we can provide and operate the MEWP ourselves. On most buildings that means one attendance instead of two — no access contractor to book, no second mobilisation, and no survey postponed because nobody could get up there.
Aerial inspection and thermographic imaging of roofs that are difficult, expensive or unsafe to reach — a full visual record without scaffold or a mobile elevating platform.
Our work is principally roofing and waterproofing. Where a leak turns out to be a façade, a window or a structural problem rather than the roof, we will tell you that plainly — and tell you who to speak to next. It costs you a phone call to find out whether it is ours.
Water ingress disputes are won on evidence and lost on assertion. Ours is traceable to something we measured, and it arrives early enough to be worth having — an honest preliminary view is cheaper for everyone than a formal report.
We take instructions from solicitors, insurers, principal contractors, roofing contractors, developers and building owners.
Most matters settle before proceedings, and an appointed expert is an expensive thing to instruct early. What is usually needed first is the technical evidence underneath an opinion: the investigation, the causation analysis and the remedial scope, prepared to be disclosed and to be tested. That is what we provide. Where proceedings need an appointed expert, we work alongside them — and we say so at instruction, not halfway through.
If the evidence doesn’t support the case, you’ll hear it in the preliminary view, not in a report you have already paid for.
Yes, if we are told the programme. Most of our work on live sites is sequenced around a following trade — we attend when the membrane is complete and before it is covered, and give the result the same day where the method allows. Tell us the date the overlay starts and we will tell you honestly whether we can work to it.
Usually not. We hold IPAF certification and can provide and operate a MEWP; where a roof does not need hands on it, a drone survey is often quicker and cheaper. Tell us what the building is and how high it is, and we will tell you what is needed. Access is the commonest reason a roof survey slips a week, and the easiest thing to solve in advance.
Because the question is not whether inspections happen, it is who carries them out and what the report tells you. A lot of inspection regimes are held by whoever was cheapest and available: cleaning contractors, gutter clearance firms, the roofer who did the last repair. Send us your last roof inspection report and we will tell you whether it was worth what you paid for it.
Yes, and more than usual. Most waterproofing warranties are conditional on a documented inspection and maintenance regime — miss it and cover can lapse quietly, often years before anybody finds out. And a warranty only covers what you can prove: if nobody recorded the condition of the membrane at handover, separating defect from fair wear becomes an argument rather than a fact.
Not before somebody has established the cause. A repair carried out first can destroy the evidence of what failed, and sometimes the warranty claim with it. If water is coming in and something must be done today, do the minimum to stop the damage, photograph it before and after, and tell us exactly what was done.
Leak investigations and expert work are priced by the day; surveys and testing are priced by area and access. You get a fixed fee or a capped estimate before we attend, never after. AP Flood Consultancy does not publish rates, because the work varies too much for a number on a web page to mean anything — and we will tell you if we think the spend is not justified.
No. AP Flood Consultancy is an independent building envelope consultancy working on roofs, decks, terraces and below-ground waterproofing across the United Kingdom. Flood is the founder’s surname, not the service. If you need a Flood Risk Assessment for a planning application, we are not the right firm and will happily say so.
Both, and more often for. A principal contractor with a leak in a building they handed over has the same problem as the client who owns it: they need to know what actually failed before anyone commits to a position. We take instructions from principal contractors, roofing contractors and specialist subcontractors, developers, building owners, managing agents, surveyors, solicitors and insurers. What we will not do is accept an instruction and a conclusion at the same time.
Often, but it is harder, slower, more expensive and less precise. Electronic leak detection is at its most valuable in the window between the membrane going down and the overlay going on. Once that window has passed, moisture mapping and forensic investigation are the usual route.
Because standing water is a cause, not a symptom. Inadequate falls shorten the life of a membrane, load the structure and turn a small defect into a persistent leak, and falls are among the first things scrutinised when a roof is disputed. Most inspections record only the membrane’s condition; ours record falls and drainage performance wherever they can reasonably be observed, in line with BS 6229:2025.
Flat roof work follows BS 6229:2025, the current code of practice — the 2018 edition it replaced has been withdrawn, so a report still written against 2018 is out of date. Electronic testing follows the RAWTA code of practice, and LRWA GN18:2025 where liquid applied membranes are involved. Below-ground work is assessed against BS 8102. Where a manufacturer’s own requirements are more onerous than the standard, theirs govern and we say so.
No, and that is deliberate. AP Flood Consultancy does not install, supply or repair waterproofing. It removes any question about why we found what we found. We will help you specify the remedial works and can review the contractor’s work once it is done.
No. We define what needs doing, to what standard and in what order; a quantity surveyor or the market puts a number on it. Keeping those two apart is deliberate. A scope written by somebody with no stake in the price is a scope you can put out to tender, compare fairly, and defend afterwards — which is not true of a scope written by whoever hopes to carry out the work.
Most water ingress matters settle before proceedings, and an appointed expert is an expensive thing to instruct early. What is usually needed first is the technical evidence underneath an expert’s opinion — the investigation, the causation analysis and the remedial scope — prepared to be disclosed and tested by the other side. That is what we provide, either as technical adviser to a party or alongside the appointed expert. We do not currently accept formal Part 35 appointments, and we say so at instruction rather than partway through a matter.
We work across the United Kingdom and the Channel Islands. London, the Midlands and anywhere within about three hours’ travel are covered at our standard rates; further afield a travel rate applies, and we tell you what it is before we set off rather than after. For planned work we would rather have seven days’ notice, though we try to be flexible and will always tell you honestly whether we can meet a date. We reply to every enquiry within one working day, and reports are issued within three working days of attendance as standard.
An independent roofing and waterproofing consultant inspects, tests and reports on roofs, decks and below-ground waterproofing without selling or installing anything. The value is not in taking readings — most equipment will produce a number — but in interpreting what the results mean: whether a defect is workmanship, product, design or fair wear, how serious it is, and what needs to be done about it. That interpretation is what a contractor, client, surveyor or solicitor can act on.
Electronic leak detection (ELD) uses low-voltage or high-voltage integrity testing to locate breaches in a waterproofing membrane — often holes too small to see. It is most effective on a newly laid membrane before it is covered by insulation, paving, ballast or a green roof. We plot every breach on a drawing, re-test after repair, and issue the results as part of a handover evidence pack.
Our office is at 3 Doolittle Yard, Froghall Road, Ampthill, Bedfordshire MK45 2NW, but we work right across the United Kingdom and the Channel Islands. Bedfordshire and the surrounding counties — Bedford, Milton Keynes, Luton, Cambridge, Northampton — London and the Midlands are all on our doorstep and covered at standard rates; further afield a travel rate applies, and we tell you what it is before we set off.
Our reports are prepared to be relied on by third parties — warranty providers, insurers and legal advisers included. If a provider has a specific format or scope requirement, tell us at instruction and we will meet it.
The most useful first conversation is a short one: what the building is, what has happened, when it started and what has already been tried. From that we can usually tell you whether this is a survey, an investigation or a dispute — and roughly what it will cost.
Not sure you need us yet? Send us your last roof inspection report and we’ll tell you whether it was worth what you paid for it.