When reading about the microbiology of the built environment there are far far more examples of the negative impacts of microbes on human health and building integrity than the reverse.
Therefore, the occasional report of beneficial applications (however theoretical) deserves mention. Today I came across this old report (behind a pay wall) from the 2005 ASM meeting talking about using biofilms of Flavobacterium johnsoniae to stabilize sand. The researchers theorize that this could be used to solidify the soil underneath earthquake-prone building and reduce the effects of seismic shaking. I tried unsuccessfully to see if anything else had come of this work, but one of the authors still lists this as a project on her website:
Stabilizing Sandy Soils With the Addition of Microbes (with the Civil & Environmental Engineering Department). Seismic loads result in an increase in the porewater pressure. In loose, sandy soils, this increase in pressure results in liquefaction of the soil. We are pursuing the use of bacteria to increase the strength of saturated sand, with the goal of possibly using this technique to reduce shifting of sandy sediments during earthquakes.
I did find another report on the use of Bacillus pasterurii to accomplish the same thing, but nothing more recent than 2007. On a similar note, there was a media flurry last year around the development of eco-friendly bricks made from bacteria, sand and urine.