| Abbreviation | Definition |
|---|---|
| HPPA | Hewlett Packard Precision Architecture |
| HSA | Heterogeneous System Architecture |
| HSDAL | High-Speed Digital Architecture Laboratory |
| HSS | Hollow Structural Section |
| HSS | Horizontal Stretch or Shrink |
| HTC | Hard-Twist Carpet |
| HTFA | High Temperature Forced Air |
| HTWSSTKS | Hiram, Tyrian, Widow's Son, Sendeth To King Solomon |
| HVAC | Heating, Ventilation, and Air Conditioning |
| HWA | Hoefer Wysocki Architects |
| HWP | Hot Water Pipe |
| HYDR | Hydraulic |
| HYDRA | Hierarchical Yet Dynamically Reprogrammable Architecture |
| I | Interior |
| I | Intrados (The interior of an arch -Architecture) |
| I/I | Infiltration and Inflow |
| IA | information architecturethe |
| IAAC | Institute for Advanced Architecture of Catalonia |
| IAAI | Iseries Application Architecture Initiative |
| IAAJ | Information Architecture Association Japan |