Thread: Painted brick

I am a superintendent on a 1914 remodel and the architect is insisting on painting the brick. I am looking for a good source of information on this. I know that Lstiburek (Building Science) mentions it in the top ten dumb things to do in the South and I am already breaking another one of the rules by having someone from the North design the house. I seem to be the only one concerned about sealing in the moisture and that includes the GC. I know that there are permeable paints but that is not what is being specked.
Any thoughts or info will be appreciated,

James

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I am not a big fan on painting bricks. However, it is done all the time. Acrylic latex paint works very well as long as proper preparation is done first. Such as power washing the brick, removing all mold, mildew, dirt, etc. Keep in mind, once you paint the brick it will need to be repainted at some point and time.

All the information I have recommends using acrylic latex or acrylic elastomeric house paint. It does not say what not to use. See examples: Prep, Prime, and Paint: Brick (The Paint Quality Institute) or painterforum free house painting advice from real painting professionals



Jeff Euriech
Peoria Arizona

James, you are correct to question paint on brick. I don't know what your exact climate is, but I think it would have to be warm and humid a large part of the year. Moisture is the culprit, sealing it inside the wall can do bad things. An older building may have MANY issues since it was not designed with a vapor barrier, insulated walls, and tight construction (air changes). When you add anything that creates a vapor barrier without thorough consideration of the effects, you might be creating a mold factory inside the walls.

You might get your designer to put it in writing that he will pay for remediation of any problems the paint creates...

Does the brick have ventilation (air space with open weep holes, etc.) on the back?

Jim,
All exterior wall are exposed, in fact that is all we kept. Everything else is new framing. From what I can tell it does have an air space between brick and sheathing (1x6) with 30# felt. We think the brick was added sometime in the 50's. We are looking into spraying close cell foam in the exterior walls to help seal and to work as a insulation/vapor barrier.

I am not familiar with the intricacies of the foam in place insulations, but I do know there are different levels of vapor permeability which should be considered.
The back ventilation of the brick should help with a degree of forgiveness since painting the face of the brick won't be able to create a perfect vapor barrier. The more moisture in the wall (which will turn to steam on a sunny exposure), the more it will try to escape through the paint, bubbling and flaking.
I still think painting brick is a stupid idea, but you might get away with it...
I might still try to get the designer to put something in writing though.

Originally Posted by James Napier

I am a superintendent on a 1914 remodel and the architect is insisting on painting the brick. I am looking for a good source of information on this. I know that Lstiburek (Building Science) mentions it in the top ten dumb things to do in the South and I am already breaking another one of the rules by having someone from the North design the house. I seem to be the only one concerned about sealing in the moisture and that includes the GC. I know that there are permeable paints but that is not what is being specked.
Any thoughts or info will be appreciated,

James

With brick veneer, I don't think it will be much of an issue. Now if the brick does not have a good moisture barrier behind it, then you could have a problem.

When the brick is painted, you ave essentially changed the cladding to a moisture barrier system, instead of a moisture drainage system. Think EIFS vs. Stucco.

The key to it working properly is going to depend on the moisture barrier (felt, Tyvek) that is installed. Proper flashing is very important as well.

Thanks guys,
Since we are leaving the brick alone (for now), I will have to trust that they put the felt on correctly. I can see the felt from where we demo the windows but I have no idea what shape it is in. There was some termite damage however no blatant water damage to the exterior wall. I am hoping that with the close cell foam insulation that we at least kept the moisture on the outside.

I can see a potential for all kinds of things as the building is being changed from 'loose and leaky' construction to 'unusually tight construction', i.e., modern energy code compliant construction.

This will have an effect on the location of the dew point within the wall, and if the dew point is moved inward and into the insulation, you will effectively be creating rain within the wall ... and that is not a good thing to do.

Then there is the brick - painting it could create high moisture levels in the wall, which could then cause efflorescence and spalling in the brick.

I see only bad outcomes for that.

If you have had termite damage as you stated, depending on where that damage was located, the felt paper could be in bad shape. Add to that, the felt paper is now (you suspect) 50 years old - felt dries out and deteriorates, so I would consider finding an inconspicuous location, remove some brick, and check the condition of the felt and the brick ties. The brick ties, if of the corrugated galvanized types, could also be rusted out, they do not last forever either.

Just a bit of thought of what might be back in there.

The Brick Institute of America has stated if a coating is not 100% vapor permeable, do Not apply it to masonry. Seems to cover it. I would love to throw a painted brick at any architect who condones painting brick. Just makes me sick. I've seen it ruin more chimneys than I can count.

I attended a talk about inspecting historic buildings recently where the speaker talked about "lime wash" as a good alternative to painting old and damaged (spalled) brick.

As you can see, the old chimneys were painted white with the concrete cap painted black. This is what the architect is want to match. The original house was siding throughout and the chimneys were painted to match the house. This is a situation were there is more money than sense. I am concerned about spalling and we are having to go back later and replace brick and paint after the roof is on.

James,
Is it on the Historic Register? If so, you may want to see what they have to say.

A finish I have been seeing is the brick is covered with a smear coat of stucco. They color the finish coat to what the want and the end product looks kind of like a stucco product with a brick pattern.

Scott,
That is actually what we did to the chimney caps so that we weren't trying to pour a 10" cap up on the roof. Do you know if you can add a specific color to the finish or if you have to deal with stock colors?

Originally Posted by James Napier

Scott,
That is actually what we did to the chimney caps so that we weren't trying to pour a 10" cap up on the roof. Do you know if you can add a specific color to the finish or if you have to deal with stock colors?

I think that you can tint it any color you want. I would check with a good paint store (not Porter) that knows how to tint other products.

Funny, they have picked out a Porter paint.

The BIA Technote on painting brick:

t6

Don't go to a paint store to get tint for stucco, go to a store which sell cement mixes (stucco, concrete, mortar, etc.) as they will have powdered tints which mix in with the powdered cement/stucco/mortar mixes.

Be aware, though, that those mixes are much more difficult to match batch-to-batch and do fade out over time (as does paint).

If they have more money than sense, then jar some sense into them - give them a price to knock down the brick chimneys and rebuild with CBS/poured (placed) concrete chimneys, stuccoed over, then paint to their hearts delight.

Michael -thanks for the technical notes.

Jerry- just got the things rebuit because they didn't meet today safety standards. This was before I knew they were painting. Although they have more money than they know what to do with, I have a Christmas 2008 deadline that I may or may not make.

Thanks for all the help,
James

Originally Posted by James Napier

Funny, they have picked out a Porter paint.

Well this tells me that they are going for Cheap and not quality. Heck, a glass of milk has more solids in it than Porter paint!