Caleulating expansion space around the en tire perimeter of Iloor between solid wood Ilooring and wall during installation was expressed in this study. Expansion space changes according to shrinkage and swelling properties of tree species used in Ilooring, size of installing area, estimating higher moisture content equilibrium to be encountered during year. AIso installation patterns and design effect expansion space. Tree species shrinkage and swelling quantities used for Ilooring is essentially important for caleulating expansion space. In general, average of unit shrinkage and swelling quantities in tangential and radial directions is used in caleulating. Considering great lounges installation with tree species of higher unit shrinkage and swelling quantities, in case of selecting straight patterns in installation and estimating biggest relative hurnadity quantity to be encountered during year, largest expansion space is caleulated. In case of choosing convinient ınstallation patterns and design for less shrinking and swelling, expansion gaps can be decreased to half or quarter quantities compared to the condition where installation pattern and design choices are not taken into consideration.