Is foam injection insulation a good way to boost the energy efficiency of my brick house?

Is foam injection insulation a good way to boost the energy efficiency of my brick house? It’s about 60 years old, and the outer walls are double brick with nothing but an open air space between them.

A lot of uninsulated brick homes like yours were built immediately after World War II, but from everything I’ve seen, adding energy efficient insulation to the air space between inner and outer bricks isn’t as easy as it looks. The challenge is always the same. The space involved can be narrow, and is often partially blocked by blobs of mortar that fell down during construction, then hardened. All this can prevent injected foam from filling the wall cavity completely, leaving hollow and uninsulatedareas. On the other hand, the only practical alternative to injection involves adding rigid sheets of insulation to the interior surface of exterior walls, and that’s a big and disruptive pain.

So here’s what I recommend: Find a contractor willing to assess the effectiveness of their insulation injection using an infrared camera. This imaging technology allows differences in heat loss to be seen visually on a screen. If hollow, inefficient areas in exterior walls are detected after the first round of injection, they can be marked and additional foam injected as needed.