Learn what's possible with the art and science of preserving our architectural past
If you don't have the answers, then you have space for the questions! In trying to preserve our heritage and "do right by" artifacts, it is imperative we ask the right questions first. The way conservators are trained, however,is to get caught up in naming ("this is a Flemish bond and that is a French polished door") even though we know from neuroscience that the minute we name something, our minds categorize it in ways that stop us from seeing detail and correlation
Biofilm removal from on top of and below waterproofing layers on these marble lions exemplifies our work on cleaning sculptures, cemetery headstones, and doing cleaning mockups on buildings in a more sensitive and long-lasting manner than is typically used.
My "Covid Vacation" began with parquetry floor repairs at the Eisenhower Building and an historic auditorium refinishing. Once these projects put me back in touch with my roots in antique furniture and musical instrument restoration, multiple opportunities for antique furniture repair materialized. The thread between these is the need to consider more than just aesthetics. In order for historic gems to last, sometimes we need to augment to strengthen original design flaws or mistakes made by other restorers. Longevity of the artwork and maintainability of finishes is equally crucial.
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.
The original 1792 Maryland State House dome retained its original paint beneath 17 later coats until 2022. What is now a demure gray and white dome was once brilliantly golden -- just as it was recorded by Charles Willson Peale when he drew the color scheme while overseeing the installation of Benjamin Franklin's first lightning rod on a public building -- an element that also remains to this day on the building where the Treaty of Paris ending the Revolutionary War was signed with the British while Annapolis was the nation's capitol.
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.
As this 1917 military structure was re-purposed into offices, the wood graining of the formwork for the concrete pours was repaired with grout and faux bois graining tools and the surfaces were casein painted in a tone that matched the reaction of high pH lime from the original concrete pour attacking the oil from the formwork and the tannins in the wood, creating a visibly soft and inviting interior to a concrete and glass structure.
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.
Site-built epoxy-impregnated carbon fiber allowed customized restraints to synch an earthquake-damaged tower and restrain lateral thrust in retaining walls, achieving a lot of stabilization within the limited funds remaining in a repointing project budget.
This is part of larger series on carbon fiber (CF). If you are just joining this blog now, please take a moment to review the previous carbon fiber repair posts. In initial attempts to determine which CF cloths and resins to use, we reviewed loads of technical literature. Too often though it was focused… Continue reading Carbon Fiber: From Woodwork to Masonry
The Preservation Science Blog 
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