Thermoporometry (TPM) was used for characterisation of porous structure of organic and carbon materials (based on melamine or cellulose acetate) by examining melting behaviour of water inside the pores. Due to specific porous features (low pore volumes, broad distribution of mesopores and small macropores), an optimisation of TPM measurements by a sample pretreatment and adjustment of experimental parameters was necessary. Removing the soluble impurities before a TPM measurement was required as the impurities affected melting of water in the pores and thus also the calculated pore size distribution (PSD). Heating rate of 1 degrees C min(-1) was optimal for resolution and separation of the peaks originating from melting in the pores and in the bulk. The best ratio of water to a sample mass ranged from 4:14 for the samples with lower mesopore volumes (approximate to 0.1 cm(3) g(-1)) to 12:12 for the samples with higher volumes (approximate to 0.4 cm(3) g(-1)). A simple procedure without separation of the overlapping peaks was used for the assessment of pore volumes and PSDs. The results of TPM measurements are reasonably in agreement with the findings from nitrogen adsorption and SEM. Only supercritically dried organic aerogel was not measurable by TPM due to shrinkage of its porous structure after wetting. (C) 2015 Elsevier B.V. All rights reserved.