According to the 2024 Economic Survey by the Kenya National Bureau of Statistics (KNBS), the construction sector registered a growth of 3% in 2023 compared to 4.1% in 2022. How many housing units were built in 2023?
Why flat roofs are gaining traction What are the challenges facing homeowners with flat roofs?
Kenya’s home style is evolving. In recent years, elegant houses with flat roofs have replaced traditional homes with pitch and iron sheets or tile roofs in new construction. The rooftop terrace has become very popular, with flat-roofed houses once reserved for coastal locations rapidly gaining momentum.
Real estate developers attribute this to reduced land sizes, the high cost of timber, and the perception that pitch houses are old-fashioned. Houses with flat roofs have increased. What are the challenges facing homeowners with flat roofs? However, Adrian Gachewa, a graduate practising architect from the University of Nairobi, explained in an interview with TUKO.co.ke that homeowners with flat roofs face several design-related challenges. These are:
1. Structural load considerations
Gachewa pointed out that flat roofs require more robust structural support than pitched roofs. He noted that additional reinforcement is crucial in Kenya’s varied terrain and climate. “Architects must carefully calculate weight-bearing capacities, especially in regions with potentially heavy rainfall. Use of high-quality, UV-resistant waterproofing membranes. Consider local rainfall patterns in Kenya (heavy rainy seasons),” he advised aspiring homeowners.
2. Space utilisation complexity
The architect cited inadequate waterproofing, poor structural integrity, and high load distribution when the roof is used to support additional loads. This, he said, requires precise engineering to fix to prevent the roof from leaking or collapsing.
The solutions include: Implementing a comprehensive structural analysis during initial design. Incorporating multiple layers of waterproofing. Designing with slight gradients to facilitate water runoff. Consult local structural engineers who are familiar with regional building conditions.
3. Material degradation
Gachewa revealed that flat roofs were more susceptible to water accumulation than pitched roofs. This means they face a higher risk of leakage and structural damage due to material degradation. “They wear faster wear due to continuous sun exposure and are more vulnerable to temperature fluctuations.
This requires more frequent inspection and maintenance as seam vulnerabilities are more pronounced,” he explained. Drainage system mitigations: Minimal slope design. Recommended minimum slope of 20mm/m. Multiple drainage points to prevent water concentration. Internal drainage systems with multiple outlets.
4. Energy efficiency implications
The construction expert said flat roofs absorb more heat in Kenya’s tropical climate. “There is a higher potential for indoor temperature increase, meaning greater cooling energy requirements,” he stated. To curb this, he recommended the following solutions: Use reflective coating materials. Implement additional insulation layers. Consider green roof technologies. Integrate solar panel installations.
Use light-coloured or white roof membranes to reflect solar radiation. What aspiring homeowners should do In conclusion, Gachewa recommended that Kenyans who want to build houses with flat roofs should seek advice from local architects experienced in regional conditions.
“They should consider traditional building wisdom alongside modern technologies and adapt the designs to local microclimates.” He said Kenyans should prioritise sustainable, locally sourced materials when possible to reduce costs.
by Japhet Ruto