For much of Kenya's property market, weather is usually treated as a background consideration. Location matters. Pricing matters. Interest rates matter. Demand matters. Infrastructure matters. But rainfall? It is often treated as something outside the investment equation. That may need to change. Kenya is heading into the October–December 2026 rainfall season with El Niño strengthening. NOAA's 10 September advisory gives greater than a 90% probability of a very strong El Niño during the Northern Hemisphere autumn and winter.

ICPAC's latest regional forecast also points towards wetter-than-normal conditions in parts of the Greater Horn of Africa. Its 10 September outlook gives a 90% chance of enhanced rainfall over north-eastern Kenya and identifies parts of central Kenya and the Lake Victoria Basin among areas with a high likelihood of seasonal rainfall exceeding 400 mm. ICPAC stresses that seasonal forecasts should be used together with shorter-term weekly and monthly forecasts. For the real estate industry, this is not simply a meteorological story. It is a property-risk story.

El Niño doesn't create every property problem

It is important to make one distinction at the outset. El Niño does not automatically mean every part of Kenya will flood. Rainfall patterns vary significantly by location, and seasonal forecasts do not tell us exactly what will happen to an individual street, development or property. What El Niño can do is increase the stress placed on vulnerable systems. And that exposes weaknesses that may already exist. Poor drainage. Blocked waterways. Inadequate culverts. Building on unsuitable sites. Poor site grading. Weak retaining structures. Insufficient storm-water capacity. Inadequate maintenance. The weather may trigger the event. But the extent of the damage often depends on the resilience of the built environment.

1. Flood risk is really a location question

One of the oldest principles in real estate is: Location, location, location. Perhaps we need to add another word: Resilience. Two properties can look almost identical. They may have the same number of bedrooms, comparable finishes and similar asking prices. Yet one may sit on a site with good drainage and natural elevation while the other depends heavily on engineered drainage infrastructure. The physical building may be similar. The risk profile is not.

This is why investors should increasingly examine not only what is inside the property boundary, but also what happens immediately outside it. Where does storm water go? How does the road network behave during heavy rainfall? Are nearby drainage channels adequate? Is the property downstream of another development? Are there rivers, wetlands or other natural drainage paths nearby? These questions can have direct financial consequences.

2. The building itself is part of the defence

Kenya's National Building Code 2024 provides an important reference point. Under its structural-design requirements, buildings are expected to be designed with consideration for flood action for a defined flood event, including resistance to flotation, collapse or significant movement caused by hydrostatic and hydrodynamic forces, scour and relevant elevation requirements.

That is significant. It means climate and flood resilience are not entirely new concepts being introduced because of the latest weather forecast. They are already incorporated into Kenya's contemporary building framework. The challenge is therefore increasingly about implementation. A code can establish standards. The industry still has to design, approve, construct, inspect and maintain buildings accordingly.

3. Construction sites face an immediate risk

For developers, an intense rainy season can affect a project long before tenants occupy it. Earthworks can become difficult. Excavations can fill with water. Site access can deteriorate. Material deliveries can be delayed. Concrete and other construction activities can become more difficult to schedule. Temporary drainage may become inadequate. And where projects are operating on tight financial models, additional delays can become expensive. A project delayed by several weeks is not simply a construction inconvenience. It can mean: higher preliminaries + delayed completion + delayed sales + delayed rental income + additional financing costs. The impact therefore moves directly from the weather into the developer's financial model.

4. Existing properties face a different test

For completed buildings, the issue becomes resilience. Heavy rainfall can expose:

• leaking roofs;
• inadequate basement drainage;
• overwhelmed storm-water systems;
• poor surface drainage;
• erosion;
• retaining-wall weaknesses;
• water ingress;
• electrical risks;
• damaged external works;
• access-road problems.

The cost is not always catastrophic. Sometimes it appears gradually through repeated maintenance. But repeated small failures can have a meaningful effect on the economics of an asset.

5. The neighbourhood matters almost as much as the building

This is an important point for property investors. A developer can build an excellent apartment complex. But the developer cannot independently control the entire surrounding drainage network. A premium apartment can still become difficult to access if the surrounding road floods. A commercial building can have excellent facilities but lose business if customers cannot reliably reach it. A warehouse can be structurally sound but suffer disruption if its logistics access becomes impassable. This means property resilience is partly private and partly public. The building matters. But so do roads, bridges, culverts, drainage networks, waterways and municipal infrastructure.

6. Climate risk could eventually influence property pricing

Kenya's property market has traditionally focused heavily on location, accessibility, amenities, rental income and capital appreciation. Climate resilience could increasingly become another variable. Not necessarily as a formal line item in every valuation today, but as part of the underlying investment assessment. Imagine two otherwise comparable properties.

Property A has strong drainage, reliable access, good site elevation, robust building design and effective maintenance. Property B has recurring flooding, poor access, drainage problems and repeated water damage. Even if both properties currently command similar rents, should an investor expect the same long-term risk-adjusted return? Probably not. That is where climate resilience starts moving from an environmental discussion into an investment discussion.

7. Insurance could become more important

Property owners often think about insurance primarily in terms of fire, theft and conventional physical damage. As extreme-weather risks become more visible, the relationship between location, exposure and insurability may become increasingly important. We should be careful not to suggest that Kenya has already developed a uniform climate-risk pricing system across property insurance. It has not. But the direction of travel is clear enough to justify a question: Could climate exposure eventually influence insurance costs, underwriting decisions and property due diligence more materially? For investors taking a long-term position in property, this is worth watching.

8. El Niño also exposes infrastructure risk

There is another layer that is sometimes overlooked. Real estate does not operate in isolation. A building depends on infrastructure. Roads provide access. Drainage carries water away. Electricity supports operations. Water systems support occupancy. Communication networks support businesses. When one component fails, the value proposition of the property can deteriorate even when the building itself remains structurally intact. This is why infrastructure investment and real-estate investment are ultimately interconnected.

9. What should developers be asking?

A serious developer should not wait for the first major storm to discover weaknesses in a site. The rainy season should prompt practical questions around:

Site selection: What is the site's drainage profile? What are the surrounding topographical and hydrological characteristics?

Design: Has the design accounted for extreme rainfall and flood risks relevant to the location?

Construction: Are temporary drainage and erosion-control measures adequate?

Materials and workmanship: Are waterproofing, roofing, drainage and structural works being executed properly?

Operations: How will the property be maintained during periods of heavy rainfall?

Access: Can residents, customers, employees and emergency services reach the property when rainfall is intense? These questions belong in the development process long before the building is handed over.

10. What should investors be asking?

The same thinking applies to buyers. Before purchasing a property, investors should increasingly look beyond the brochure. Ask: Has the area experienced flooding before? Where does surface water go? How is the building drained? What happens to the basement during heavy rainfall? How accessible is the property during extreme weather? What is the condition of the surrounding infrastructure? What maintenance has historically been required? These questions may not make a property look more attractive. But they can make an investment decision more intelligent.

11. The long-term implication for Nairobi

Nairobi's continued development means the relationship between urbanisation and storm-water management will become increasingly important. As more land is built over, natural drainage pathways can be altered and runoff patterns can change. That puts greater pressure on engineered infrastructure. The question is therefore not only: How many buildings are we constructing? It is also: Are we building enough resilience into the urban system around them? This is where urban planning becomes inseparable from property development.

12. The NCA connection

This is also where our recent discussion about the National Construction Authority becomes particularly relevant. NCA's Building Code 2024 is intended to establish a contemporary framework for planning, design, construction, maintenance and demolition. NCA itself has also emphasised the need for sustainable and resilient construction practices in implementing the new Code, including recognition that changing weather conditions require adaptation in construction practices. So perhaps the El Niño conversation is actually another way of asking the question we raised in our NCA discussion: How well are we building?

13. From property quality to property resilience

For years, the definition of a high-quality property has largely revolved around: Location + design + finishes + amenities. The next phase may increasingly add: + resilience. A resilient property may not necessarily be the most expensive building. It is the one that is better able to continue functioning when conditions become difficult. That distinction matters. Because climate events can turn apparently inexpensive shortcuts into expensive liabilities.

Our View

El Niño should not be treated as a reason to panic about Kenya's real estate market. It should be treated as a reason to prepare and ask better questions. For developers, it is a reminder to take site conditions, drainage, design and construction quality seriously. For investors, it is a reminder that property value is influenced by more than the building itself. For policymakers and infrastructure agencies, it highlights the importance of drainage, roads, storm-water management and coordinated urban planning.

And for the broader property industry, there is a larger lesson. Resilience is becoming part of real-estate quality. The most valuable property in the future may not simply be the one in the best location or with the best finishes. It may be the one that continues to perform when the conditions around it become difficult. El Niño may come and go. The question is whether our buildings are prepared for it.

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