Construction of an All-Wall Radiator for use with lower temperature Heat Pumps. The room is about 16m2 (160 sqft), the 3 outside walls are insulated internally with 37mm of foam on 50mm plasterboard/drywall (37/12mm). The cavity wall has ~100mm of older rockwool floc filling. Two wall radiators were removed on opposite walls, on under the window the other on this internal wall. The heat wall was designed to cover the full wall which is 3m (10ft) wide by 2.4m (8ft) high.
The floor is screed, but only has about 25mm (1") of insulation. It would be difficult to install underfloor heating. So the heat wall was designed to heat the room without having a visible wall radiator and facilitate the move to a heat pump in the future.
The wall is internal, so any heat loss through the wall remains in the house. It was first backed with insulation, then vertical battens were fixed to create 5 recesses. Within these recesses it has 5 sets of 1m x0.5m of upper and lower aluminium back panels, a single copper (15mm) meander, the copper pipe is then sandwiched with an upper and lower front panel. The top and bottom panels are separated to allow for the joint and warm air to flow out. The top outer panels have a large hole, again to allow warm air to flow. The reclaimed wood (old pallets) are then spaced to allow warm air convection. The meander was plumbed into the existing radiator circuit.
One of the wooden slats near the bottom right is held in place with cupboard door magnets to allow easy access to the radiator valve, for adjustment. I have not scientifically measured the heat output yet, but it is more than sufficient to heat the room, we have to turn it down, it works too well!