If you are going to small villages, do not even look toward any construction being done in Cairo, Joberg, etc.
Based on what I have seen in Africa and similar locations, you will have to use your engineering background on what materials are currently used and available. Looking at already constructed buildings will give you insight into the short term performance. Do not expect to get any meaningful test reports on the materials.
Much of the needed construction is low rise without great loads due to ability of the available flooring/roofing systems to span large areas or carry heavy loads. You will find many traditional construction methods that have been made more effective because of excellent "local engineering".
The range of construction is very broad. You will find a great deal of masonry construction because of the historic development and local availablity. Poured concrete can be extremely variable because of the raw materials and limited batching facilities. Delivery in portions of the country limit the size of pours. Masonry units can range from rammed earth block to low quality concrete brick to very high quality colored concrete.
If you are going to be in somes countries (South Africa, Botswana, Namibia, etc.) you will find a tradition of good construction based on some British standards, but mainly German (dating back about 50 years or more). As you go out of the cities, your selection of materials will decrease. In a large portion of South Africa, there are some very fine low cost homes built using basic 6" block and readily available materials. I have also seen some very good construction in Ghana, where quality masonry is common and many floor systems are a traditional beam with block fillers and a concrete topping/fill.
Do not understimate the local professionals. - When I saw construction techniques that amazed me in South America, I asked the engineer what code he used and his answer was "We use your codes, but we use them better".