Laying Topflor Step 3 The panels have to follow the line of the wall. If the wall is not straight, the line of the wall should be marked on the first (still unglued) row of panels. Then saw along the panels according to the markings. Align the row exactly (use the plumb line as a control) so that the groove and tongue joints can be pressed together tightly and form a straight line. Begin the second row with the remaining piece from the previous row. However, the joints of each row of panels should be staggered by at least 40 cm in relation to the previous row. This will ensure an optimum flow of your Topflor decor! Next - Laying Topflor Step 4