Recovering Stained Facade
The facade of our house is a yellowish-beige sandstone, not limestone, and not the usual brownstone. It has a lot of grimy gray staining which did not come off when we attempted to clean it about 10 years ago, at great expense. Now I’m wondering what we can do to make the place look nicer….
The facade of our house is a yellowish-beige sandstone, not limestone, and not the usual brownstone. It has a lot of grimy gray staining which did not come off when we attempted to clean it about 10 years ago, at great expense. Now I’m wondering what we can do to make the place look nicer. Will grime like this ever come out? Should I consider re-covering the whole thing as I’ve seen some people do? Or paint? (Many of the houses on our block are painted, though I know it’s considered sacrilege it certainly looks tidier than our dirty house.) The house is on a landmarked block, so I’m constrained by what they’ll allow. Thanks for any ideas.
Gosh, I guess we have a consensus!
Yes, I believe I was told by the LPC that it’s Ohio sandstone.
I’m not concerned about the green algae (it is north-facing),which I have just scrubbed off with plain water and a brush in the past. ( I would never use bleach for any purpose–terrible for our waterways.)
It’s the grey discoloration that has bothered me–seems dingy compared with some of the the fresher-looking houses on the block. But you all have helped me see it in a different light–patina! Thanks, everyone.
I really like the patina and look of your facade! If you do clean it again please don’t use bleach. Washing it off sends the bleach into the sewer, groundwater, sidewalk and tree pits; you’d harm or kill any trees in front. It’s toxic. Baking soda is a miracle substance, we use it to clean anything and everything and it’s not toxic.
for me it looks beautiful as it is.
Please don’t paint it. The paint seals moisture underneath so it can’t evaporate. The result is that the stone itself is eaten away and deteriorates. Paint has destroyed many brownstone facades. I think it looks great, antique patina befitting a 100-year old house.
Chlorine bleach: sodium hypochlorite
Baking Soda: sodium bicarbonate
Soda Ash (Washing Soda): sodium carbonate
Application of a dilute solution of any will temporarily create a more neutral pH on your building’s surface; the last two are kinder (environmentally).
My idea of a perfect paint job: http://bit.ly/9BLTYG
It looks like an Ohio sandstone, or something similar, and it is beautiful. It is obviously a pretty dense and sturdy stone, as opposed to many brownstones, so it retains its detail much better. Other than the discoloration, there is no reason to stucco it or otherwise cover it.
LPC would not allow it to be painted. It’s a bad idea anyway (for all the reasons others have said and more), but it’s also a non-starter. LPC would allow to reface the building IF it was in poor condition, but it isn’t.
As others have noted, the staining could be natural discoloration of the stone (inclusions within the stone reacting to water), in which case you really just have to live with it. It could also be staining from biological growth, which can be cleaned with dilute bleach solutions, TSP or proprietary bio/fungicides). The best course of action is to hire an architectural conservator to look at the stone and do a series of cleaning tests. That will give you a neutral party identification of the best way of removing the staining. The conservator can also work with your contractor to make sure they are doing the work properly.
I agree with DIBS and almost everyone else. It’s beautiful, don’t paint it, and don’t worry about the discolorations. They don’t distract from the house’s natural beauty. Try the bleaching/cleaning, but don’t do anything else! The stone doesn’t look like it’s even been chipped, and that’s pretty good for 100 years. It’s in excellent shape. That’s what’e really important.
I know I’m repeating, and I know you said you tried cleaning before, but diluted bleach seems to do wonders for all sandstone/ concrete surfaces. That algae/ moss gets on everything.
I know I’m repeating, and I know you said you tried cleaning before, but diluted bleach seems to do wonders for all sandstone/ concrete surfaces. That algae/ moss gets on everything.