Nairobi, Kenya, faces significant challenges in sustainable urban development, including rapid population growth and environmental degradation. A multi-disciplinary approach was employed, combining architecture, urban planning, and computer science techniques. A mixed-methods research strategy involved case studies and expert interviews to gather comprehensive data. Through analysis of architectural designs and environmental impact assessments, a key finding is that incorporating passive solar design principles can reduce energy consumption by up to 40% in new village constructions. The study concludes with the development of an eco-friendly building design toolkit for sustainable village construction, which includes guidelines on material selection and construction techniques. Recommendations include government incentives for green building practices and community engagement strategies to promote adoption of these designs. Eco-Friendly Design, Sustainable Village Construction, Nairobi, Kenya Model estimation used $\hat{\theta}=argmin_{\theta}\sum_i\ell(y_i,f_\theta(x_i))+\lambda\lVert\theta\rVert_2^2$, with performance evaluated using out-of-sample error.