Sustainable construction nowadays requires the use of environmental friendly materials with high rate of insulation. Straw construction presents some advantages such as renewability with low energy input, recyclability, CO2 storage, and local availability that implies short distribution cycle. However, before the introduction in the construction industry, attention needs to be paid to the construction technology using such natural materials. In this paper there were developed elements of enclosing structures for two technologies of straw frame building; was done thermal modeling of potentially weak assembles of building envelope; were calculated R-values and then compared with normative indexes; was evaluated efficiency of usability two technologies of low-raise building in cold and wet conditions of St. Petersburg.