Final answer:
Construction below the Base Flood Elevation should use flood-resistant materials due to the high risk of flooding. Wood is susceptible to water damage, and while it can be used technically, it is not recommended as per the NFIP guidelines.
Step-by-step explanation:
When building in a floodplain, the National Flood Insurance Program (NFIP) has specific regulations about constructions below the Base Flood Elevation (BFE). According to these regulations, the areas below the BFE are at high risk of flooding, and certain precautions must be taken to prevent flood damage. While some parts of a house, such as the foundation or the columns supporting the elevated portion of the house, can be built with flood-resistant materials like concrete, there is a recommendation against using wood for the areas that could be underwater during a flood event.
This is because wood is susceptible to water damage, such as warping, rot, and mold growth, which could ultimately compromise the structural integrity of the house during a flood. Therefore, while it might be technically possible to use wood, it is advisable to follow the best practices laid out by NFIP and instead use materials that are more flood-resistant for any portion of the structure that lies below the BFE.