Retrofitting adds new technology or features to an existing structure. It is different from renovation, which improves the appearance or function. Retrofitting upgrades the performance. It can make a building more energy-efficient, more earthquake-resistant, or more accessible. It can add insulation, replace windows, install solar panels, or strengthen the foundation. In the kitchen, the closest equivalent is upgrading an old appliance. The cook replaces the old stove with a new one. The cook adds a new gadget. The cook improves the function. It is not retrofitting. But it is an upgrade. It is the retrofitting of the kitchen. It is the retrofitting of the cook.

Seismic retrofitting is one of the most important types. Many older buildings were built before modern earthquake codes. They lack the reinforcement and ductility to survive a strong quake. Retrofitting can add steel braces, shear walls, foundation bolts, and moment frames. In the kitchen, the upgrade can add a new vent hood, a new dishwasher, or a new refrigerator. The improvement is the same. The goal is the same.

Energy retrofitting is another common type. It can add insulation, seal air leaks, upgrade windows, replace furnaces, and install heat pumps. It can reduce energy bills and carbon emissions. In the kitchen, the upgrade can add an energy-efficient appliance. It can reduce the energy bill. It can reduce the carbon footprint. The retrofitting is the upgrade. The upgrade is the retrofitting. Both are the same. The same is the kitchen. The kitchen is the retrofitting. The retrofitting is the cook. The cook is the retrofitting. The retrofitting is the same. The same is the meal. The meal is the retrofitting. The retrofitting is the same.