Geothermal heating is an environmentally friendly and energy efficient method to supply newer and well insulated houses with heat. The investment costs are higher than for gas or oil heating, so there is a need to investigate the possibilities of arranging heat collectors in the subsurface efficiently.This model compares three different pipe arrangements, embedded in the subsurface of the top soil layer in a garden, used for radiant floor heating. Typical thermal properties of the soil layer are obtained using interpolation and piecewise functions.