| Abbreviation | Definition |
|---|---|
| NFPOO | Not Foreseeable Physical Obstructions Or Conditions |
| NFS | Not Frigging Stable |
| NGC | New Generation Construction |
| NHBRC | National Home Builders Regulatory Council (South Africa) |
| NHCA | National Hispanic Construction Association |
| NHCC | National Housing and Construction Company |
| NHCI | No Hub Cast Iron |
| NHCL | National Housing and Construction Limited |
| NHCS | New Horizon Construction Services |
| NIBS | National Institute of Building Sciences |
| NIST | National Institute of Standards and Technology |
| NKBA | National Kitchen & Bath Association |
| NKCM | Nano Metakaolin Cement Mortar |
| NLTF | North LPG Tank Farm (Kuwait) (project name) |
| NMEJ | Non Metallic Expansion Joints |
| NMFS | National Marine Fisheries Service |
| NNF | Not Normally Flowing |
| NOAA | National Oceanographic and Atmospheric Administration |
| NOC | Notification Of Construction |
| NOI | Notice Of Intent |