What is that black stuff growing on our buildings? Biofilm cleaning challenges for buildings

Biofilm growths on the Jefferson Memorial with laser cleaned slice showing, 2018

Black slime is attacking our national monuments and buildings ... and it's all our fault. The methods of building cleaning the last 30 years have created a difficult to remove biological soup on our buildings. Here is why we need to change our ways.

Successful Preservation Project Management: Using Feedback Loops During Project Design

The scaffolded "drop" or mockup area where conservator and contractor learned side-by-side during the first month before final bidding.

Preservation projects are nothing like new construction since there are unknowns. Because they are normally bid just like new construction, the surprises that arise later make preservation projects more expensive. Too often risk mitigation on restoration projects means increasing the budget 50% or more. This isn't necessary. By reserving the first month of the project for on-the-scaffold investigations by the conservators with the key members of each team of tradesmen, optimal details can be developed and any training needed to show tradesmen new skills can occur before contractors finalize their bids for the project.

Tough access: Drones and other budget inspection and maintenance tools

Using drones to inspect inaccessible areas on a routine basis or after storms is a prudent diagnostic technique we have been using since 2013 and should be part of annual historic site maintenance and any initial planning for projects. This post also touches on the use of gel disks to sample and determine types of staining material and the best non-destructive methods for remediation.

Carbon Fiber Repair for Historic Buildings, Intro

Stabilization with carbon fiber is a very cost-effective and preservation-oriented option for deteriorated building elements.