NAIROBI, Kenya (AP) -- Kenya has an affordable housing problem. The government plans to build 250,000 houses each year, with the aim of eventually closing a housing deficit that World Bank data puts at 2 million units. But experts say construction and financing need to change and speed up for the housing deficit to be met. Some are exploring the emerging technology of 3-D printing for home construction. One company CEO says the technology can help address the huge housing need on the African continent, but it will take time. For now, prices remain out of reach for most Kenyans.