A hydronic radiant flooring heating system includes a pipe having pipe sections, and a grid of a thermally conductive material. The pipe sections are arranged substantially parallel to one another along a first axis, where there is a second axis perpendicular to the first axis. The pipe is to carry a heated liquid to radiantly heat a flooring under which the pipe is situated. The grid is situated relative to the sections. A portion of the grid is positioned substantially parallel to the second axis, and has an increased gauge to provide for lateral heat flow from the sections along the second axis. Heating of the flooring under which the pipe and the grid are situated is substantially uniform at least partially due to the increased gauge of the portion of the grid positioned substantially parallel to the second axis, while permitting wider spacing between adjacent of the pipe sections.