  When materials freeze, they often undergo damage due to ice growth. Although
this damage is commonly ascribed to the volumetric expansion of water upon
freezing, it is usually driven by suction of water towards growing ice
crystals. The freezing of this additional water can cause a large build up of
stress. Here, we study this process by producing a stable ice/water interface
in a controlled temperature gradient, and measuring the deformation of the
confining boundary. Analysis of the deformation field reveals stresses applied
to the boundary with $\mathcal{O}(\mu\mathrm{m})$ resolution. Globally,
stresses increase steadily over time as liquid water is transported to more
deeply undercooled regions. Locally, stresses increase until ice growth is
stalled by the confining stresses. In accordance with the Clapeyron equation,
the local limiting stress is proportional to the local undercooling. These
results are closely connected to the crystallization pressure for growing
crystals and condensation pressure during liquid-liquid phase separation.
