This is the frost-protection assembly I built for the Ark rainwater catchment tank drop pipes. I used 3/4" foam building insulation, pinned together with nails and then caulked and painted. The top door provides access to the control valves. The bottom door is so I can change light bulbs whenever they burn out. The foam box provides adequate protection most nights. For extra-cold nights, I use a 60-watt incandescent light bulb in the bottom to provide a little heat. Incandescent bulbs produce 10% light and 90% heat, so they make an excellent heat source for a variety of applications.
This foam box protects the drop pipe and control valves for the greenhouse water tank. The door at the bottom provides access to the light bulb, which is hooked up to a timer so I don't have to walk all the way up there to turn it on. The ladder and garden hose means I'm still pumping water from my well into the tank, using a little electric pump. Hopefully this will be the year when I'll finally install my solar-powered submersible pump to fill the tank.
