The Brick is Stripped! For Real!
We can breathe a big sigh! It’s been 4 months of early mornings and tedious work. But the brick probably hasn’t looked this good in 50 years. It looks extra good from a distance, but the cleaning didn’t get it completely perfect. I’d call this satisfactory, but if it’s feasible to do even better I’m willing to give it another day or 2.
Starting at the bottom, the first floor window sills and the marble base were covered in what I believe was white alkyd enamel. I followed manufacturer recommendations and applied Stripper Cream, a caustic, over solvent based AcryliStrip, and the two together did a good job removing the paint. There are also a lot of spalls in the marble. I’m planning to use a consolidating treatment to hopefully make this area more durable to slow down the decay.
Moving up from there, the brick was coated with what I believe was red latex paint. But the bottom 3 feet or so had a weird brown coating, I believe bituminous paint, under that, which made the peeling even worse. I used Prosoco Fast Acting paint stripper until switching to more effective AcryliStrip and got just about all of that off. I’m happy!
Then I used One Restore, an acid based detergent cleaner, for the pollution stains. It took off some of that and cloudy red residue from the paint and returned the brick to its original orange-red color. Where the bituminous paint was it looks brand new! But elsewhere the black dirt blotches remain. They still look a lot better because the brick is clean. This is known as dry pressed brick, and is hard to clean because it’s dense yet porous.
Below this bedroom window sill the staining is worse and although it’s gotten lighter, it looks like it might not come off, right?
But wait! The other sill right next to it has no staining under it now! So what did I do right?
Then, the first floor lintels and all the second floor marble had what I believe was a traditional oil based paint. It dissolved with the application of caustic paint stripper. Both Prosoco’s heavy duty paint stripper and EaCo Chem’s stripper cream were effective here. But this marble has a rough, sugary texture as a result of the carbonate dissolving over time. And on the surface are ugly grey to black stains that I believe are gypsum that formed from the marble itself reacting with sulfur from air pollution.
So, the brick looks pretty good now, but not completely consistent. I’m interested in getting it better but would rather have some stains than damage it with an overly aggressive cleaning method. See next door, where the brick is really clean because the smooth texture was blasted off. The neighbor’s scrub pointed mortar joints were also inappropriate but that’s a subject for another post.
As for the marble… I’m not okay with the stains. Either I find a chemical to clean them off, or I sand it down to clean marble again, or I use a (breatable, non peeling) mineral based masonry stain to correct the coloring and make the upper marble come close to matching the marble at the bottom.
Sanding the marble would probably make me a bad preservationist. But I might do it anyway. Anyone have thoughts on the issue?
11 Responses
That looks amazing. Watching you do this over the last few months, I honestly didn’t know if the brick would be salvageable. Great Job!
Here’s a piece on maintaining historic marble (if you haven’t already seen it). The authors seem to like washing with water and a brush… probably the safest approach to start with. Unfortunately, I don’t think there is any easy or convenient solution – if there was we would probably already know about it:
http://www.hoffarch.com/assets/Vol-22-N1-Historic-Marble-and-Limestone-Structures.pdf
Your house is looking really nice… it’s come a long way!
I read about genetically engineered sulfite reducing bacteria produced by an undergraduate student project in Italy. I did not find any way to purchase the bacteria, or to have them shipped to the United States if I could.
I read that The Cloisters in New York used laser ablation to clean the column capitals in their outdoor collections, but I don’t believe the lasers are available at Taylor Rental.
I read that chelation primarily works by undercutting the stains. Since I don’t have a clean surface on the marble anyway and it’s not elaborately carved, I don’t have a huge problem with this. But then, if eroding the surface with EDTA deepens the pores and leaves it with more space for further degradation in the future…
It doesn’t look so bad to smooth them out with a sander. And my dad used to work on cars a lot when he was younger and is totally up for taking it on.
The other option is that LimeWorks sells silicate mineral based paints that don’t form a vapor barrier or a film that will peel. I could buy a translucent color wash in a color similar to the clean parts of the marble and paint out the stains. By their recommendation, I will be fogging the whole facade with water glass (which is also the base of the paints) as a consolidating treatment. They tell me this will be very good for the sugared marble and a prerequisite for patching the spalls and holes. (I don’t want to patch the shallow spalls in the marble.) I could also use the color wash to correct the color of a Portland cement patch around my hose bib where the old oil tank intake used to be. I know they tell me that dissolved salts in my historic masonry will attack the Portland cement and that it should all come out and be replaced with a lime based patching material, but I don’t want to mess with a repair that goes all the way through the wall and has a water line in it.
Bravo to you for all that work!
I’m guessing you have already thought of trying bakingsoda?
I dont want to use any abrasives, even mild ones
I’m just totally amazed at how awesome it looks!!! i mean, as a person not used to seeing brick, if i walked by your house i’d go “WOW” because it looks so great! i’d never notice the stains. i had to go back and study your first pic to even see what you were talking about.
Yeah I get surprised to see all the wooden buildings up your way! One of the reasons that I want it cleaner is that most of the houses around mine were overzealously cleaned in a way that damaged them, but when you stand on the street I stick out as a dirty one. Which is still prettier than the ones with vinyl siding over the brick of course but still.
This is just me, but I am comfortable with a little imperfection. You bought a cool old house – it is OK to show the history.
The only reason I don’t like it is that the bottom of my house did come out perfectly clean, and the clean parts blend in better with the block.