Property, construction and housing · Playbook 46

Damp and mould risk prediction (social housing)

Surveyors visit the homes most at risk of damp and mould before anyone has to report it. Every tenant report still starts the Awaab's Law clock, and a person makes every decision about a hazard.

  • Predictive ML
  • Agents with tools
  • Human in the loop
  • Event-driven integration
  • Awaab's Law
  • RSH consumer standards
  • Housing Ombudsman
  • UK GDPR

At a glance

The problem
Damp and mould is found when a tenant reports it, often after months of harm, and the data that could have warned the landlord sits in five different systems
Typical volume
Around 30,000 homes, 2,500 damp and mould reports a year, and sensors in about 3,000 homes whose households agreed
Who's involved
Asset and property services, the damp and mould team, surveyors, housing officers, the contact centre, data protection, tenant panel
Pilot
10–12 weeks after a 3–4 week discovery
Platforms
AWS, Azure, or a sovereign or on-prem stack

An illustrative scenario. The numbers are typical examples, not a client case study. The cloud services and UK rules were checked on 9 November 2026.

The business problem

Most social landlords find damp and mould the same way: a tenant phones, fills in a web form or tells a housing officer. By then the mould is visible, and it may have been affecting the household's health for months. Some households never report it at all, because they've been told before that it's condensation, because they're worried about their tenancy, or because nobody asked.

The warning signs are usually already in the landlord's data, but scattered. The stock condition survey knows which archetypes have solid walls, poor ventilation or a history of roof leaks. The repairs system knows about the extractor fan that was reported broken twice, and the leak from the flat above. The contact centre knows about the call that mentioned a child's asthma. Sensors in some homes show humidity staying high for weeks. Nobody sees all of it together, so surveyors are sent where reports come in, not where the risk is.

Since 27 October 2025, Awaab's Law has set fixed timescales once a landlord is aware of a potential damp and mould hazard. More hazards follow from 30 November 2026. The Regulator of Social Housing expects landlords to understand the condition of every home, and the Housing Ombudsman has spent years asking landlords to move from reactive to proactive handling and to stop blaming tenants' lifestyles. Finding risk earlier is the obvious next step, as long as it never slows down the reports that already exist.

What AI changes

  • Stock condition, repairs history, sensor readings, complaints and contact records are brought together for each home, so the landlord has one view of damp and mould risk across the stock.
  • A risk model ranks homes by the likelihood of damp and mould, with the reasons for each score: a building defect, a repeat leak, a broken fan, sustained high humidity.
  • Each week, an agent drafts a proactive visit list for the damp and mould team to approve, with a short pre-visit pack for each surveyor.
  • Sustained sensor readings above agreed limits create a task for a person to review within a fixed time, because the government's guidance says consistent readings should prompt timely investigation.
  • Every tenant report goes straight to the existing Awaab's Law process and starts the clock, exactly as it does today. The model only adds visits. It never delays, downgrades or closes a report.
  • Surveyors decide whether a hazard exists, and the damp and mould team decides what happens next. The landlord learns which signals really predicted damp, and fixes the causes across whole blocks and archetypes, not one home at a time.

How success is measured

Agree these, and measure the baseline, before anything is built. Example targets are typical, not promises.

Found before a report

Share of damp and mould cases first identified by a proactive visit rather than a tenant report.

ExampleRising each quarter, from a measured baseline

Visit hit rate

Share of proactive visits that find damp, mould or a cause that needs work. Too low wastes surveyor time; very high can mean the list is too cautious.

ExampleAbove the rate for randomly chosen homes, and reviewed monthly

Awaab's Law timescales met

Investigations, written summaries and safety work completed on time, for every case, however it was found.

ExampleEvery case, with no change for reported cases

Repeat damp and mould

Homes with a new damp and mould case within 12 months of the last one being closed.

ExampleDown by a third

Data coverage

Homes with a current stock condition record and the fields the model needs, such as ventilation and heating type.

ExampleAbove 90% of the stock

Fair reach

Proactive visits and outcomes split by area, building type and household group, including households with recorded vulnerabilities.

ExampleNo group worse off

UK regulation and controls

Cross-sector rules are on the UK regulation map.

  • MHCLGAwaab's Law (Social Housing (Regulation) Act 2023, s42; Hazards in Social Housing (Prescribed Requirements) (England) Regulations 2025)

    Once the landlord is aware of a potential significant damp and mould hazard, it must investigate within 10 working days, give the tenant a written summary within 3 working days of the investigation ending, and complete safety work within 5 working days. Emergency hazards must be investigated and made safe within 24 hours. A tenant report starts the clock whatever the model says, so reports never pass through the model. Proactive visits sit on top of this process. When a visit finds a potential hazard, that starts the clock too, and the system records the date.

  • MHCLGAwaab's Law guidance: environmental monitoring and household circumstances

    The guidance says a sensor's risk notification doesn't necessarily mean the landlord is aware of a hazard, but consistent readings that show potential issues should prompt timely investigation. So sustained readings create a task with an owner and a deadline, not a silent score. Landlords should take vulnerabilities at face value, and the same hazard may need a faster response for one household than another. That judgement is made by a person, using the vulnerability records, not by the model.

  • RSHSafety and Quality Standard and the other consumer standards (in force since April 2024)

    Landlords must have an accurate, up-to-date understanding of the condition of every home, and use it to keep homes safe and decent. The risk model is a way of using that data, not a substitute for stock condition surveys. Its outputs feed the stock condition plan and investment decisions, and they would stand up in an RSH inspection. The Transparency, Influence and Accountability Standard means tenants are told how their data is used, and the tenant panel helps shape the design.

  • Housing OmbudsmanComplaint Handling Code (statutory since 1 April 2024) and the spotlight reports on damp and mould and on knowledge and information management

    The Ombudsman's 2021 spotlight asked landlords to take a zero-tolerance approach, move from reactive to proactive handling, and stop blaming lifestyle. Its later reports tie good outcomes to accurate records of repairs, inspections and household vulnerabilities. Nothing the system produces, including the model's reasons, letters and surveyor packs, suggests the tenant caused the damp. Complaints still follow the Code's timescales: acknowledge within 5 working days and respond at stage 1 within 10 working days of acknowledging.

  • ICOUK GDPR and the Data Protection Act 2018: sensor and household data

    Readings from sensors inside a home are personal data, because they can reveal when people are in, cooking, bathing or heating. That means a DPIA before the pilot, a lawful basis agreed with the DPO, sensors installed only where the household agrees, readings used only for keeping the home safe, and a short retention period. Occupancy patterns are never used for tenancy enforcement or anything else. Health and vulnerability data is special category data and is used by people to set urgency, not as a model input.

  • ICOAutomated decisions (UK GDPR, as amended by the Data (Use and Access) Act 2025)

    The model doesn't take decisions about tenants: it adds homes to a list that a person approves, and every hazard decision is a surveyor's. Even so, the design keeps the safeguards the new rules expect: tenants can be told why a visit was offered, can ask for one themselves, and can challenge a finding with a person.

  • EHRCEquality Act 2010, including the public sector equality duty for council landlords

    A model trained on past reports learns who reported, not only where damp was. Households less likely to report, for example because of language, disability or fear about their tenancy, can be under-ranked. The fairness measures check reach and outcomes by group, and the visit list keeps a share for homes with little data.

The solution

Showing AWSAzuresovereign / on-prem services. Switch with the toggle; every diagram and table on this page follows it.

Damp and mould risk prediction (social housing): reference architecture
  1. 01Channels

    • Tenant reports: phone, web, app, housing officer
    • Environmental sensors (homes that agreed)
    • Surveyor and contractor findings
  2. 02Intake

    • API Gateway (or AWS IoT Core)API Management (or Azure IoT Hub)Kong, or an MQTT broker (e.g. Eclipse Mosquitto)Sensor readings from the sensor platform
    • AWS GlueData Factory in Microsoft FabricApache AirflowExtracts from housing systems
    • Amazon S3 + Timestream for InfluxDBOneLake + Fabric Real-Time IntelligenceCeph or IONOS S3 Object Storage + TimescaleDBHome-level data store
  3. 03Intelligence

    • SageMaker AIAzure Machine LearningMLflow and Kubeflow on KubernetesDamp and mould risk model
    • Lambda on a scheduleFabric ActivatorRules in a Temporal workflowSensor rules: sustained readings
    • Agent
      Bedrock AgentCoreFoundry Agent ServiceLangGraph on Kubernetes, with open-weight models via vLLMVisit planning agent
  4. 04Orchestration

    • Step FunctionsLogic Apps / Durable FunctionsTemporalVisit and review workflow
    • EventBridge + SQSEvent Grid + Service BusApache Kafka or RabbitMQEvents and queues
  5. 05Systems of record

    • Housing management and repairs system
    • Asset and stock condition system
    • Contact, complaints and vulnerability records
  6. 06People

    • Person
      Damp and mould team: approves the list
    • Person
      Surveyor: decides if there's a hazard
    • Person
      Housing officer: household support
  • Cloud or platform service (AWSAzuresovereign / on-prem)
  • AI agent
  • A person decides
  • Your existing systems
  • Outside your organisation

Components, side by side

Damp and mould risk prediction (social housing): components on AWS, Azure and a sovereign or on-prem stack
LayerAWSAzureSovereign / on-prem
Sensor readingsMost landlords buy sensors as a service, so take readings from the provider's API. Don't build on Azure IoT Central, which retires on 20 September 2029, or AWS IoT Events, which has ended.API Gateway receiving readings from the sensor provider's platform; AWS IoT Core if gateways connect directlyAPI Management receiving readings from the sensor provider's platform; Azure IoT Hub if gateways connect directlyKong, or an MQTT broker (e.g. Eclipse Mosquitto) feeding Apache Kafka
Time-series historyKeep hourly summaries, not every raw reading, and delete them on a set schedule. Timestream for LiveAnalytics is closed to new customers.Timestream for InfluxDBFabric Real-Time Intelligence (Eventhouse)TimescaleDB or InfluxDB
Housing data pipelineNightly extracts of stock condition, repairs, complaints and contact data, keyed on the property reference. Fixing that key is often half the work.AWS Glue, Amazon S3Data Factory and OneLake in Microsoft FabricApache Airflow, with PostgreSQL or Apache Iceberg on Ceph
Risk modelGradient-boosted trees on home-level features usually beat anything fancier here, and are easier to explain to surveyors and tenants.SageMaker AIAzure Machine LearningMLflow and Kubeflow on Kubernetes
Reasons and fairness checksSageMaker Clarify and Model Monitor closed to new customers on 30 July 2026, so new AWS builds run these checks in their own pipeline.Open-source libraries (e.g. SHAP, Fairlearn) in SageMaker AI PipelinesAzure Machine Learning Responsible AI dashboard and model monitoringOpen-source libraries (e.g. SHAP, Fairlearn) in MLflow and Kubeflow pipelines
Summaries and pre-visit packsBoth clouds offer a choice of models, including Claude. The pack summarises the home's history; it never gives a view on the cause.Amazon BedrockMicrosoft FoundryOpen-weight models served with vLLM on your own GPUs, or IONOS AI Model Hub
Agent runtimeThe original Bedrock Agents closed to new customers on 30 July 2026; new builds use AgentCore.Amazon Bedrock AgentCoreFoundry Agent ServiceAn open-source agent framework (e.g. LangGraph) on Kubernetes
Workflow and eventsAWS Step Functions, EventBridge, SQSLogic Apps or Durable Functions, Event Grid, Service BusTemporal, Apache Kafka or RabbitMQ
Link to the housing management systemAgree in discovery what your housing system supplier's API allows: creating an inspection request, or only reading.API Gateway, plus your existing integration platform if you have oneAPI Management, plus your existing integration platform if you have oneKong or your existing API gateway, plus your existing integration platform if you have one
Human reviewThe list and the reasons appear where the team already works, next to the open Awaab's Law cases.In the damp and mould team's existing case toolIn the damp and mould team's existing case toolIn the damp and mould team's existing case tool
GuardrailsBlocks wording that blames the household, such as lifestyle or drying clothes, in packs and drafts.Bedrock GuardrailsFoundry guardrails (Azure AI Content Safety)Open-source guardrails (e.g. NeMo Guardrails, Llama Guard)
Identity, permissions, keysSensor data is visible only to the damp and mould team and surveyors, not to tenancy enforcement.IAM Identity Center, Amazon Verified Permissions, KMSEntra ID, Azure RBAC, Key Vault, PurviewKeycloak or your existing Active Directory; OpenBao or HashiCorp Vault; an HSM
Monitoring and auditLog every score, every list, every approval and every visit outcome, with the model version.CloudWatch, CloudTrailAzure Monitor, Log AnalyticsPrometheus, Grafana, OpenTelemetry
UK data residencyIONOS AI Model Hub runs in German data centres: EU, not UK, residency. Check where the sensor provider stores readings, too.eu-west-2 (London)UK South / UK WestYour own UK data centre, or a UK or EU provider

On a phone, the table shows the platform you pick. Sovereign / on-prem means open, portable components you can run in your own data centre or with a UK or European provider; IONOS is shown as one example, and others exist. What sovereign cloud means →

Hybrid and on-prem

Many organisations keep core systems and sensitive data on their own servers. This is how the same design works across both.

Stays on-prem

The housing management system, the asset and stock condition system, and the contact and vulnerability records stay where they are. Many councils and housing associations still run these on their own servers or with a hosted supplier, and nothing here needs them to move.

Uses cloud AI

The home-level data store, the risk model, the sensor rules and the visit planning agent can run in AWS or Azure, or on your own servers with open-weight models. Only the fields the model needs leave the housing systems: property reference, building attributes, repair codes and dates, and sensor summaries. Names and health details stay behind.

How they connect

Nightly extracts and change events over a private link (AWS Direct Connect or Azure ExpressRoute) and the API layer. Approved visits come back as inspection requests through the housing system's API, so they appear in the normal repairs workflow.

If the link drops

Nothing about tenant reports changes, because they never depended on the model. The damp and mould team works its existing cases as before, sensor readings queue at the provider, and the next visit list is drafted when the link returns.

The agents

What each agent may do through its tools, what it may not, and where a person signs off. The limits are enforced by the platform, not the prompt.

Visit planning agent

May do

  • Read the week's risk scores and the reasons behind each one
  • Check whether a home already has an open report or Awaab's Law case, and leave it with that case if so
  • Check recent visits, repairs and planned works for each home
  • Draft a proactive visit list for the damp and mould team, with the reasons for each home
  • Draft a pre-visit pack for each surveyor, summarising the home's repair and inspection history
  • Create draft inspection requests in the repairs system, marked as awaiting approval

May not do

  • Close, merge, defer, reprioritise or downgrade any tenant report or Awaab's Law case
  • Decide whether a hazard exists, or record a hazard decision
  • Contact a tenant or book a visit without approval
  • See or use health details, or change a vulnerability record
  • Use sensor or occupancy data for anything other than damp and mould risk

Where a person signs offThe damp and mould team approves every proactive visit, and a surveyor decides every hazard. Reports from tenants never pass through the agent. Its permissions are enforced by the platform's identity and policy controls, not by instructions in a prompt.

Middleware and integration

The housing management system stays the record for every report, inspection and Awaab's Law case. The AI reads from it through an API layer and nightly extracts, and writes back only draft inspection requests that a person approves. If you already run an integration platform, the AI uses it like any other system.

Tenant reports follow their own path, untouched. A report reaches the damp and mould team through the existing process and starts the clock the moment the landlord is aware of it. The risk model runs alongside, never in front, so a model outage, a bad score or a slow pipeline can't delay a report.

Events keep the parts decoupled. Each sustained sensor alert, approved visit and visit outcome becomes a message on a queue, with an ID so a retry never creates a duplicate inspection. Visit outcomes flow back into the training data, so the model learns from what surveyors actually found.

The model can be switched off without affecting anyone's safety. If it's paused, proactive visits stop and everything else carries on exactly as it did before.

Process and people

  • A named owner in the damp and mould team for the weekly visit list, with a set number of proactive visits each week so the list can't crowd out reported cases.
  • A sensor review rota: every sustained-reading task has an owner and a deadline, and the decision is recorded.
  • Surveyors record what they found, and its causes, in a structured form, so the model is retrained on findings, not on who reported.
  • A monthly review of the visit hit rate and fair-reach measures, with the tenant panel seeing the results each quarter.
  • A named owner for the model, the sensor limits and the guardrail wording, with change control like any other system.
  • Staff trained before go-live on what the model can't see, and on never using lifestyle as an explanation.

Delivery plan

  1. 3–4 weeks

    Discovery

    Map the data across the housing, asset and contact systems, fix the property key, measure the baseline, agree the sensor data terms, and meet the tenant panel.

  2. Gate · must be true to passBaseline agreed, data access confirmed, DPIA started, lawful basis for sensor data agreed with the DPO.

  3. 10–12 weeks

    Pilot

    One area or archetype, in shadow mode first: the model ranks homes, surveyors visit a sample from the top of the list and a random sample, and the hit rates are compared.

  4. Gate · must be true to passHit rate clearly above the random sample, no group worse off, no effect on reported cases, and sign-off from the head of property services.

  5. 4–6 weeks

    Production

    Weekly visit lists go live for the pilot area, with sensor review tasks, monitoring, support and a rollback plan.

  6. Gate · must be true to passMonitoring, support model, rollback plan and staff training in place.

  7. Ongoing

    Scale

    Extend across the stock, then reuse the same data foundation for the hazards Awaab's Law adds from 30 November 2026, such as excess cold.

  8. Gate · must be true to passEach new area or hazard passes the same pilot gate.

Roles and RACI

Who is responsible, accountable, consulted and informed, by activity
ActivityDirector of propertyProduct ownerSolutions architectI can fill thisTechnical PMI can fill thisEngineersI can fill thisDamp and mould leadDPOSecurityI can fill this
Business case and benefitsAccountableResponsibleConsultedConsultedInformedConsultedInformedInformed
Target architecture and data integrationInformedConsultedAccountable and ResponsibleConsultedConsultedConsultedConsultedConsulted
DPIA and sensor data termsAccountableConsultedConsultedInformedInformedConsultedResponsibleConsulted
Model build and fairness testingInformedConsultedAccountableConsultedResponsibleConsultedConsultedInformed
Pilot visits and hit-rate comparisonInformedAccountableConsultedResponsibleConsultedResponsibleInformedInformed
Go-live decisionAccountableResponsibleConsultedResponsibleInformedConsultedConsultedConsulted
Run, monitor and improveInformedAccountableConsultedConsultedResponsibleResponsibleConsultedConsulted

Business case and benefits

Director of property
A · Accountable
Product owner
R · Responsible
Solutions architect
C · Consulted
Technical PM
C · Consulted
Engineers
I · Informed
Damp and mould lead
C · Consulted
DPO
I · Informed
Security
I · Informed

Target architecture and data integration

Director of property
I · Informed
Product owner
C · Consulted
Solutions architect
A/R · Accountable and Responsible
Technical PM
C · Consulted
Engineers
C · Consulted
Damp and mould lead
C · Consulted
DPO
C · Consulted
Security
C · Consulted

DPIA and sensor data terms

Director of property
A · Accountable
Product owner
C · Consulted
Solutions architect
C · Consulted
Technical PM
I · Informed
Engineers
I · Informed
Damp and mould lead
C · Consulted
DPO
R · Responsible
Security
C · Consulted

Model build and fairness testing

Director of property
I · Informed
Product owner
C · Consulted
Solutions architect
A · Accountable
Technical PM
C · Consulted
Engineers
R · Responsible
Damp and mould lead
C · Consulted
DPO
C · Consulted
Security
I · Informed

Pilot visits and hit-rate comparison

Director of property
I · Informed
Product owner
A · Accountable
Solutions architect
C · Consulted
Technical PM
R · Responsible
Engineers
C · Consulted
Damp and mould lead
R · Responsible
DPO
I · Informed
Security
I · Informed

Go-live decision

Director of property
A · Accountable
Product owner
R · Responsible
Solutions architect
C · Consulted
Technical PM
R · Responsible
Engineers
I · Informed
Damp and mould lead
C · Consulted
DPO
C · Consulted
Security
C · Consulted

Run, monitor and improve

Director of property
I · Informed
Product owner
A · Accountable
Solutions architect
C · Consulted
Technical PM
C · Consulted
Engineers
R · Responsible
Damp and mould lead
R · Responsible
DPO
C · Consulted
Security
C · Consulted

R ResponsibleA AccountableC ConsultedI Informed· not involved

Where I'd fit

Option A

Lead the architecture

If there's no architect on the programme, I'd own the design end to end: the home-level data foundation, the model and its checks, the integration with your housing management system, and the gates. I'd make sure tenant reports stay on their own path, and I'd report to your programme board.

Option B

Support your architect

If your partner or your own team already has an architect, I'd take on the data pipeline, the model and the agent under their lead, and give them a second senior opinion on integration, data protection and the Awaab's Law process.

Where this goes wrong

  1. Goes wrong

    Reports start going through the model, and a low score becomes a reason to wait.

    How the design avoids it

    Reports never touch the model. The clock starts on awareness, and the agent has no permission to change a case.

  2. Goes wrong

    The model learns who reports, not where damp is, and keeps missing quieter households.

    How the design avoids it

    Train on surveyor findings, measure reach by group, and keep part of each list for homes with little data.

  3. Goes wrong

    Sensor readings sit on a dashboard nobody owns.

    How the design avoids it

    Sustained readings become tasks with an owner and a deadline, and the decision is recorded.

  4. Goes wrong

    The model's reasons drift into blaming the household.

    How the design avoids it

    Features describe the building and its repairs, not behaviour. Guardrails block lifestyle wording, and the tenant panel reviews the letters.

  5. Goes wrong

    Stock condition data is years old, so the model is confidently wrong.

    How the design avoids it

    Measure data coverage as a KPI, and treat every proactive visit as a chance to update the stock condition record.

On the horizon

Changes already announced or under way that affect this design. More in the UK horizon scan.

  1. From 30 November 2026
    Awaab's Law phase 2: excess cold, excess heat, falls, structural collapse, fire and explosions, electrical hazards and domestic hygiene, where they present a significant risk of harm. Parliament approved the amending regulations in October 2026.

    The same home-level data and sensor temperatures help with excess cold. Make sure the reporting and triage process covers the new hazards before 30 November, whatever the model does.

  2. 2027
    Awaab's Law phase 3 extends the timescales to all remaining HHSRS hazards except overcrowding. The HHSRS itself was updated in June 2026, with 21 hazards and three bands.

    Store survey findings against the updated HHSRS hazard list, so the data foundation serves every hazard, not only damp.

  3. By 1 April 2030
    Social rented homes must reach EPC C on one reformed EPC metric, under the minimum energy efficiency standard confirmed in 2026.

    Retrofit can cause damp if ventilation isn't right. Use the model and sensors to check homes before and after works.

  4. 2035
    The new Decent Homes Standard applies, with a new damp and mould criterion alongside Awaab's Law.

    Record damp and mould findings in a form you can report against the new criterion, so you can see progress well before 2035.

  5. 2026–2027
    The ICO's code of practice on AI and automated decision-making, required by regulations in force since May 2026.

    Keep the model's reasons, the approvals and the visit outcomes in a form you could show the ICO and your tenants.

Questions to ask your partner or vendor

Good answers are specific. Vague answers to any of these are worth following up.

Copy them into your next supplier meeting

  1. How do we know a tenant report can never be delayed by the model?
  2. What does the model learn from: who reported, or what surveyors found?
  3. Who owns a sustained sensor alert, and how quickly must they act on it?
  4. How are households who rarely report kept from being ranked low?
  5. What sensor data do we keep, for how long, and who can see it?
  6. What does it cost to run per thousand homes, at our stock size?

Planning something like this?

Whether you need someone to lead the design or to support the architect you already have, let's talk it through.

Sam Naseem
Sam NaseemBirmingham, UK · UK & Europe
Available now