In this thesis is introduced a thorough renovation of a row house built in the 1980s and the reasons that led to it focusing on moisture resistance. The Technical quality of a small house -systems applicability for renovation projects was also examined in this thesis, although the system is originally designed for the developers to improve the quality of new constructed small houses.

The importance of moisture resistance was also examined in this thesis. In addition the construction practices and techniques used in the 1980s and the problems concerned with them were also studied.

Technical quality of a small house -system, originally developed for new construction, is also widely suitable for renovation targets. It is understandable, that some of the design solutions are impossible or unreasonable to carry out in the renovation targets. However, with studying and understanding the system it is possible to find out new aspects where adjustments may significantly extend the life cycle of the building.

The two-storey row house examined in the thesis is located at Luotolaisentie in Oulu. Biggest concerns of the house B were the wrong inclinations of the site and the structure used in the house in which the external skin of the foundation wall was lifted above the bottom of the frame of the external wall, which together eventually led to moisture damage. Also the air slots were almost clogged or they did not exist at all. Vapour check barriers and the thermal insulation of the roof slab were also faulty and the installations should have had been done more carefully. The soil under the building is capillary and thus the ground moisture rises to the structures causing damage.