Basement Heating

The reason that the concrete wall has a honeycomb look to it is because the contractor did not mix the concrete properly. It does not mean that there is any structural flaw in the wall. Honeycombed or not, the concrete wall is worth less than R-1, which means that as much as 20 percent of your heating bill goes through those walls. If there is no water leakage through the wall, there is not much to worry about. Apply some parging to the honeycomb wall. After it dries, I would suggest adding some insulation. The best, and easiest, insulation to add flush to a concrete wall is rigid foam paneling, and over that some drywall. You will lose a little bit of floor space in the basement, but it will be much warmer and your heating bills will drop.