Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
mātĕrĭo (no perf.), ātum, 1, v. a. [materia], to build of wood (rare but class.): eaque aedificia minime sunt materianda propter incendia, Vitr. 5, 12, 7: aedes male materiatae, of bad wood-work, Cic. Off. 3, 13, 54.
* mātĕrĭor, āri, v. dep. [materia], to fell or procure wood: erat eo tempore et materiari et frumentari necesse, Caes. B. G. 7, 73 init.