Do Radiant Heating Panels need to be mounted above peoples heads to be effective?

The answer, in short is no!

Solray Panels can be positioned either in the centre of the room, or at the perimeter, along one or more walls.

When positioned in the centre of the room, the radiant heating from the Solray Panels will directly warm the floor below, and any objects including people. This can sometimes cause mild discomfort for people sat directly below the panels

Central Panel Arrangement

Central Panel Arrangement

The radiant effect falls off as you move away from directly underneath.
Where the Solray Panel is away from the wall, the wall itself will not be directly heated; it will be indirectly heated by the re-radiation from the warmed floor and by the convection currents in the room.

Cold external walls and windows may not be heated enough to warm them, which will mean unequal temperatures in the room, degrading comfort.

When Solray Panels are positioned along the perimeter of the room, the radiant output strikes the wall and windows underneath directly, overcoming any cold spots.

Perimeter Panel Arrangement

Perimeter Panel Arrangement

Being on the room perimeter, the Solray Panel does not directly warm all the floor and objects throughout the room. However the warmed wall re-radiates to the room, providing heat to all objects and surfaces.
Because these internal surfaces have a much smaller heat loss than the external wall, the secondary radiation is sufficient to heat them, and give a constant temperature throughout the room.

Utilising the full wall lengths within the space regularly results in panels being narrower which further increases the comfort for the occupants as well as the equal spread of heat.
In terms of install, the panels typically have one connection per room meaning that the need for pipework and valves to each room is substantially reduced.

Perimeter mounting also aids ceiling co-ordination in that central ceiling services such as lighting is not interfered with.