Natural alternative building materials have been used widely worldwide due to its environmentally friendly and cost effectiveness. Natural alternative building materials have also been found to be strong and durable as compared to construction materials in modern construction systems. However, the natural alternative building materials are not completely acceptable due to its hazard impact. Its unacceptance has been linked to lack of standard code for Health and safety. The paper examined different types of natural building materials for construction and standard codes for health and safety in alternative construction system. Findings show that natural alternative building materials for construction are mostly unacceptable under the local construction codes. The unacceptance of the natural alternative building materials for construction are mainly as a result of a limited number of skilled personnel’s and trained workers in the use natural alternative building materials, lack and shortage of materials during construction and inability for other trades to function effectively within the system. Further findings show that building code should be enforced in the use of natural alternative building materials within the built environment to protect the health and safety of individuals. The paper concluded by emphasising on the acceptability of natural alternative building materials based on cost effectiveness, environmental friendliness and adaptability to meet the required standard code for health and safety.