This is a report on the research done on the moisture diffusion in a solid wood wallwithout a vapour barrier. The goal is to determine whether or not the wall will pass thegeneral criteria on moisture conditions with an added load of moisture from the insideof the building. Measurements of the wall conditions are taken with sensors mountedinside the wall and are compared against hand calculations to see if they coincide.Data for the temperature and relative humidity has been collected from mid-Januaryto March and are presented in the form of tables and diagrams. Both the collecteddata and the hand calculations indicate values over the critical limit. These values aremostly observed during the summer season, in the part of the wall that is nearest tothe outside. Hand calculations even indicate that condensation will occur in the wallduring the winter season’s coldest months, but further hand calculations show that thewall has a high enough desaturation capacity for the condensation to evaporate duringthe warmer months of the year.The results show that this kind of wall is applicable, with reservation for circumstantialconditions, in a sub arctic climate such as Lule˚a, Sweden. Although further studies withmore refined calculation methods should be made to verify these results.