Dear PoP – Exposing a Brick Wall, Finding Matching Mortar?

Photo by PoPville flickr user AWard Tour

“Dear PoP,

I am exposing a brick wall in my house. It was never covered in plaster (it was an old attic space that had wood paneling over it and then dry wall over that) so its not going to be a huge pain to clean it off. But, the biggest problem I’m facing is that the mortar is old and there are some small gaps here and there. The mortar is a very light sand color and the texture is a bit chunkier than today’s mortar. I’ve been reading on the internet that the best bet is to talk to people who have done this before, masons, other homeowners, to see how they matched mortar for similar houses from the same year. According to my internet research, even in big cities, different builders usually used very similar mortar from house to house with sand from the same place and with similar mixes and technique. It is a bayfront townhouse built in 1904, so if anyone has any experience with matching mortar, or knows where I could get more resources, I could really use the help! Thanks.”

42 Comment

  • From my (limited) understanding, it’s not so much that you want to match the color, but you want to match the material used back them.

    I’d strongly recommend Frager’s Hardware on Penna Ave SE for some guidance.

  • pablo .raw

    The mortar has to be similar to the old one, if not when the mortar contracts because of temperature, cracks are going to come back.

  • I’d consider repointing the entire area you expose. The aesthetic difference between a brick wall that’s just been patched and one that’s been repointed is striking.

    It actually might be easier in the end to do the entire area.

  • yup. ask at fragers. absolutely.

    • They will direct you to Virginia Lime Works and you can pick up your order at Frager’s. The people at VLM know their stuff (check out their website) and I have found them to be extremely helpful over the phone too. You send in a sample, they analyze it for content and color, and send you what you need to fix it. Don’t use regular mortar you buy at the store, at best it will look wrong and at worst it will ruin your brick. Also be sure to test any matte sealants before applying them. It took us five tries to find one that was actually matte. Good luck!

  • You cannot match brick. You just can’t. You can get close, but it will not be exact. Don’t dick around and talk to an experienced mason about this.

    • I’m not trying to match the brick, I’m trying to match the mortar. I’d love a recommendation for an experienced mason, if you have one.

      • You’ll never match the mortar, but if anyone can can come close, it’s Edgar’s Masonry.

      • Ignore this dufus. Go to Fragers. There are two types of mortar appropriate for DC there: fine and coarse. If it’s indoor and you already have coarse aggregate, use that. You can use the fine, but it’s only really necessary for butter joints or the front facade of your house. Everywhere else it’s coarse. The difference between the two is just the ratio of sand with fine being 1:1 and coarse being 2:1. If you want to match really large sand chunks, buy a bag of sand at Home depot –the coarse kind, not the kids sandbox kind and mix that in to the fine mortar.

        As for color you can either custom order it based on chipping out a small sample, or mix your own with some color (they can order color for you). Mix some small batches with different ratios of color and let them dry until you find something that matches.

        There’s nothing that the pros do that you can’t, with the possible exception of working on scaffolding which I personally wouldn’t do.

        You’ll also need to buy a trowel and a chisel that fits the width of your mortar joint. Also you need the L shaped thing for pushing the morter into the groove. The groove needs to be chipped out 3/4. You should pre moisten the brick overnight or at least a few hours before you start. Best results if the brick is damp but not dripping wet. If you spray the brick with water and it wicks away immediately, keep wetting.

        The only time I’d pay someone is the facade, or if I won the lottery and decided to do the entire house at once.

  • I have a similar problem. The exposed walls are in leaving spaces so color matching for aesthetic reasons IS an issue, in addition to using the correct type of materials. The previous owners (who exposed the walls) tried to match the color but clearly didn’t match the material. To piggy-back on the question: How big of a problem is this? If it is just cracks in the mortar that will have to be dealt with later, fine. But I don’t want to damage the brick. I have a big enough list of semi-urgent projects without adding removing mortar to it.

    • (*Living spaces.* Long day.)

    • Removing mortar is time consuming but you have to have zero fine motor control to damage the brick. Buy a hammer and an angled chisel that’s thinner than the width of your joints. Remove 3/4″ depth, no more. Start at the top of the wall. I’d say do 5-6 rows of bricks and then fill them back in with mortar. The next weekend, do another 5-6 rows.

  • Thanks for the help so far. It hadnt occurred to me to go to Fragers, but I should definitely go do that.

    Pablo and Poon: I see your points. Both things I had thought of, but the wall space is probably about 70 square feet. Of that, if you took all the gaps and put them end-to-end, you probably wouldnt get up to a foot. So we’re talking about a very minimal amount. I guess, if I have to redo it all, I’ll consider it – but I’m trying very hard to avoid it! I’m happy that the wall is in such relatively good condition, thats the reason I’m considering exposing it in the first place. If it needs to be completely repointed, I might just cover it up with sheetrock.

    If you guys know of someone who has done some masonry restoration, please post their info, so I can get in touch.

    • pablo .raw

      If it’s just a cosmetic thing, maybe you can try to match it with grout for ceramic tiles? it comes in different tones and you may be able to match the existing color or getting very close. You can probably do it yourself and I don’t think it is too expensive. Just an idea.

  • Guys…
    Most of those interior exposed brick walls are the 2nd or 3rd course of brick so you technically don’t “have” to do anything. I would personally repoint it myself, but don’t worry about using a special lime mixture. If this were exterior and your joints were narrow, we would be dealing with a completely different situation, but because they are interior and are not subject to the harsh freeze-thaw cycle you are fine with conventional repointing.

    Whatever you do, don’t let someone dupe you out of thousands trying to “restore” something that was never meant to be exposed (aesthetically).

    • I would advise against using any old mortar. You probably shouldn’t use mortar with concrete in it. It’s not appropriate for DC bricks.

    • LocalDeveloper:

      My interior walls were patched with nothing special. Now a white (almost chalky looking) residue has developed on the brick around the new mortar. Seems like what you use might matter.

      Wish I knew what the white was and whether to worry about it! Anybody?

      All, thanks for the informative thread.

      • That always happens and I believe it’s related to the lime? An expert could correct me.

        Nevertheless, you can wash that with a solution of soap and water.

      • White chalky substance on brick is called efflorescence. A DIYer or bad mason had too much salt in their mortar. Cure rate was probably off too. Efflorescence doesn’t damage the strength of the mortar, but it is ugly.

      • The reason why this happened is that the moisture that hits the outside of the bricks “breathes” into the inside bricks. It allows them to dry completely. It’s also why you don’t coat your interior brick walls in plastic of non-breathable insulation.

        The efflorescence can be cleaned. Probably diluted muriatic acid is the most straight forward. Do some internet research.

  • We repoint a ton of brick. Use a small grinder to cut out the loose sections of the mortar. Your best option is to cut out all the mortar, because the new mortar will never exactly match the old. This is dusty work- it makes a mess- but it’s easy to do. Go to Ernest Mayer on Bladensburg Road to buy cement made for repointing an interior wall. Tell them it’s for a historic wall and they will show you a chart with about 15 colors. You then mix it with sand- you can also buy sand here- to make the mortar mix. Use a small tool- you can buy it here as well- to make the flat joint. When you’re totally done, use a gentle cleaner like Spic and Span to clean all the dust off the wall. I wouldn’t recommend using a sealer because it will get shiny and can look yellow. Good luck. You can email me if you want more advice.

  • Okay, first of all, it’s not really what you think it is in there. If your house is really old, it’s before concrete was invented, so the stuff is probably just lime and sand, which is how they’ve done it since roman times.

    After time, water washes away the lime and you are left with just sand in the places that got exposed to water. So how do you match it?

    1) take a chunk of undamaged cement and put it in a cup with hydrocloric acid. The HCL will combine with and remove the lime and leave only the sand.

    2) go to different places and match the sand as closely as possible.

    3) mix the sand with lime and you’re set, it will match the original. DO NOT use regular cement. It’s harder than your bricks and will crack it.

    If you want to short cut it, maybe you can use structo lite intstead of the lime and mortar and just repoint, but don’t use regular old portland cement. The old bricks are soft and when they expand and contract they will expand into the much harder portland cement and crack the bricks.

  • I’m currently working on what you’re trying to do. The best bet is just using grout for ceramic tiles if there is nothing structurally wrong with the wall. If that’s the case, then they sell TONS of different ‘light beige’ colors for grout at Home Depot (linen, butter cream, sand, dawn, etc…) I just went yesterday and it’s $13.27/ 25 lb bag. I have a guy that got a lot of it done for only $200/day. After the grout dries, I go back and sand it down for a smooth surface to seal. As someone previously mentioned, go with a low-luster sealer (unless you want it really shiny). If you want a visual of it post grout, I could run down to the basement and take a picture!

    • I’d love to see a picture, if that is possible. I am just trying to get the aesthetics correct, no structural concerns at all.

      I hadnt thought of grout at all, that sounds like a good idea. Any idea how that will hold up with the sealer? Or is the sealer the same stuff you’d use on tile/grout in a bathroom?

  • You guys are a fountain of knowledge!

  • I recently got my roof recoated and the company told me that I should have a clear sealant put on my bricks so I can have all the gaps filled in and never have to get a it repointed. Is this a good idea? Has anyone done this?

    • It’s a terrible idea. Like undercoating for a new car. Sounds like a good idea (doesn’t actually do anything) and is easy to apply (huge profit margin for the salesman pitching it). Save your money.

    • The problem is that the brick and mortar need to breath. You need to get the moisture out of the bricks after it rains. If you seal it, any water that gets in –and it will get in, stays in there and damages everything.

  • Sure, I can send a picture… where should I send it to? The last post was my virgin post so I don’t really know what I’m doing. And yes, the sealer will do fine with the grout.

    • I dont really want to post up my email address for the whole world. You could upload it to the popville flckr pool and post the link? I’m not sure how these things are done, either.

  • There was a “This Old House” episode where they redid a house in either shaw or U Street that had to have the mortar matched. If you can find the episode, they might mention where they got the matching sand from.

  • I just redid my 100 year old chimney. With the really old fragile old brick you really want to choose a mix that doesn’t have a lot of cement, go for the lime. If the cement content is high, the brick will break before the mortar, what is easier to fix? Mortar any day.

    For color mixes amd all the varieties of lime/cement mix, definite best bet for quality service nearby DC is Ernest Maier in Bladensburg. I plan to go there quite soon for a mortar repair job on my big old rock wall crack.

  • Is anyone interested in practicing on or learning on someone else’s home? I’ve still got brick work in the basement that I’m repointing from replacing the basement windows. I’d be willing to show people how I do it for a bag of mortar or an hour’s worth of help.

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