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mortar on old rowhome


John Dirks Jr

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I'll be doing a renovated city rowhome tomorrow. It's listed as being built in 1900. It's obvious from the picture they did something with the mortar. How should I approach checking this out? I'm worried if they might have used harder mortar than the original stuff which could lead to problems.

How best do I examine this?

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Maybe it'll be one of the few that was done correctly. The bright white might be a good sign. http://www.oldhouseweb.com/how-to-advic ... onry.shtml Take a close-up pic to show us the method of repointing too.

View across and up the facade wall to see if there's any significant bulging or sweeping. Look into the window jambs for separation. There are far too few brick headers for interlocking the wythes.

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Looks like a decent re-pointing job (materials compatability aside.) And, it looks like a decent brick. If things look as nice close up as they do in this picture, I'd simply mention that re-pointing is a science, which if done wrong, can accelerate deterioration. You have no way of knowing how it was done. Feel free to shoot me closeup pics of any area that concerns you, John.

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Maybe it'll be one of the few that was done correctly. The bright white might be a good sign. http://www.oldhouseweb.com/how-to-advic ... onry.shtml Take a close-up pic to show us the method of repointing too.

View across and up the facade wall to see if there's any significant bulging or sweeping. Look into the window jambs for separation. There are far too few brick headers for interlocking the wythes.

I see exactly what your talking about with regard to the sparse headers. Great observation Bill. Thanks for your help.

Is there a way to tell by scratching a the mortar if it's softer like it should be or would recognizing that take an experienced mason or other?

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Looks like a decent re-pointing job (materials compatability aside.) And, it looks like a decent brick. If things look as nice close up as they do in this picture, I'd simply mention that re-pointing is a science, which if done wrong, can accelerate deterioration. You have no way of knowing how it was done. Feel free to shoot me closeup pics of any area that concerns you, John.

Thanks Mike. I'll be sure to post any concerns I find here at the forum.

So, does the correct softer mix of mortar typically have a lighter shade such as in this picture? How can the condition of the adjoining units affect this one?

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John, regarding turn of the century mortar: My pop was one of the assistants to the Architect to the US Capital. They elected to have the Capital power Plant re-pointed (built around the same time as your subject house). The masonry contractor came back to my dad asking for a considerable change-order, because the mortar was

so hard. They flatly abandoned the project. It was not a Portland based mortar. (Not all lime based mortars are soft. If it's mixed and cured properly it can be quite hard.)

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Looks like a decent re-pointing job (materials compatability aside.) And, it looks like a decent brick. If things look as nice close up as they do in this picture, I'd simply mention that re-pointing is a science, which if done wrong, can accelerate deterioration. You have no way of knowing how it was done. Feel free to shoot me closeup pics of any area that concerns you, John.

Thanks Mike. I'll be sure to post any concerns I find here at the forum.

So, does the correct softer mix of mortar typically have a lighter shade such as in this picture? How can the condition of the adjoining units affect this one?

John, this is where it gets a bit tricky. As I'm confident Bill will agree, if the brick is as hard as nails, then mortar hardness is far less of a concern. So start there. If the brick appears well fired (dark shades of red and very dense and hard), there probably isn't that high a potential for future damage, even if they did use a harder mortar. But, if the brick are poorly fired - lighter shades of red and porous/soft, then mortar compatiability becomes critical.

All of that aside, another more cosmetic tragedy in re-pointing is bringing the new mortar out flush to the face of the brick, if the brick edges have weathered (rounded). Doing this makes the joints appear fatter than they actually are , because of the rounded brick edges (simple geometry). If the bricks are weathered, you need to stop the mortar right where the weathering of the brick edge begins, and slick the surface right there. Make sense?

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Looks like a decent re-pointing job (materials compatability aside.) And, it looks like a decent brick. If things look as nice close up as they do in this picture, I'd simply mention that re-pointing is a science, which if done wrong, can accelerate deterioration. You have no way of knowing how it was done. Feel free to shoot me closeup pics of any area that concerns you, John.

Thanks Mike. I'll be sure to post any concerns I find here at the forum.

So, does the correct softer mix of mortar typically have a lighter shade such as in this picture? How can the condition of the adjoining units affect this one?

John, this is where it gets a bit tricky. As I'm confident Bill will agree, if the brick is as hard as nails, then mortar hardness is far less of a concern. So start there. If the brick appears well fired (dark shades of red and very dense and hard), there probably isn't that high a potential for future damage, even if they did use a harder mortar. But, if the brick are poorly fired - lighter shades of red and porous/soft, then mortar compatiability becomes critical.

All of that aside, another more cosmetic tragedy in re-pointing is bringing the new mortar out flush to the face of the brick, if the brick edges have weathered (rounded). Doing this makes the joints appear fatter than they actually are , because of the rounded brick edges (simple geometry). If the bricks are weathered, you need to stop the mortar right where the weathering of the brick edge begins, and slick the surface right there. Make sense?

I understand what you're saying Mike. Just to be clear, bringing mortar out flush to the face over rounded edges as you mentioned, that's just a cosmetic issue, correct?

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Looks like a decent re-pointing job (materials compatability aside.) And, it looks like a decent brick. If things look as nice close up as they do in this picture, I'd simply mention that re-pointing is a science, which if done wrong, can accelerate deterioration. You have no way of knowing how it was done. Feel free to shoot me closeup pics of any area that concerns you, John.

Thanks Mike. I'll be sure to post any concerns I find here at the forum.

So, does the correct softer mix of mortar typically have a lighter shade such as in this picture? How can the condition of the adjoining units affect this one?

John, this is where it gets a bit tricky. As I'm confident Bill will agree, if the brick is as hard as nails, then mortar hardness is far less of a concern. So start there. If the brick appears well fired (dark shades of red and very dense and hard), there probably isn't that high a potential for future damage, even if they did use a harder mortar. But, if the brick are poorly fired - lighter shades of red and porous/soft, then mortar compatiability becomes critical.

All of that aside, another more cosmetic tragedy in re-pointing is bringing the new mortar out flush to the face of the brick, if the brick edges have weathered (rounded). Doing this makes the joints appear fatter than they actually are , because of the rounded brick edges (simple geometry). If the bricks are weathered, you need to stop the mortar right where the weathering of the brick edge begins, and slick the surface right there. Make sense?

I understand what you're saying Mike. Just to be clear, bringing mortar out flush to the face over rounded edges as you mentioned, that's just a cosmetic issue, correct?

No. Actually, soft weathered brick with rounded edges pointed out to the face of the brick with excessively hard mortar is the WORST possible combination. The wider cementicious joints act as a bit of a dam - preventing moisture from evaporting from the brick corners. This is preciesely what accelerates the deterioration, through freezing and expansion. THAT is the scenario that causes major brick face spalling - where the face is deeply receeded (deteriorated away).

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Looks like a decent re-pointing job (materials compatability aside.) And, it looks like a decent brick. If things look as nice close up as they do in this picture, I'd simply mention that re-pointing is a science, which if done wrong, can accelerate deterioration. You have no way of knowing how it was done. Feel free to shoot me closeup pics of any area that concerns you, John.

Thanks Mike. I'll be sure to post any concerns I find here at the forum.

So, does the correct softer mix of mortar typically have a lighter shade such as in this picture? How can the condition of the adjoining units affect this one?

John, this is where it gets a bit tricky. As I'm confident Bill will agree, if the brick is as hard as nails, then mortar hardness is far less of a concern. So start there. If the brick appears well fired (dark shades of red and very dense and hard), there probably isn't that high a potential for future damage, even if they did use a harder mortar. But, if the brick are poorly fired - lighter shades of red and porous/soft, then mortar compatiability becomes critical.

All of that aside, another more cosmetic tragedy in re-pointing is bringing the new mortar out flush to the face of the brick, if the brick edges have weathered (rounded). Doing this makes the joints appear fatter than they actually are , because of the rounded brick edges (simple geometry). If the bricks are weathered, you need to stop the mortar right where the weathering of the brick edge begins, and slick the surface right there. Make sense?

I understand what you're saying Mike. Just to be clear, bringing mortar out flush to the face over rounded edges as you mentioned, that's just a cosmetic issue, correct?

No. Actually, soft weathered brick with rounded edges pointed out to the face of the brick with excessively hard mort is the WORST possible combination. The wider cementicious joints act as a bit of a dam - preventing moisture from evaporting from the brick corners. This is preciesely what accelerates the deterioration, through freezing and expansion. THAT is the scenario that causes major brick face spalling - where the face is deeply receeded (deteriorated away).

Got it. It was because you said "cosmetic tragedy" in your previous post that had me asking to make sure. I understand that there are various combinations of right and wrong. The span can run from just fine to totally whacked. I'll just have to see what I find tomorrow.

It might be raining so I wonder if that would hide efflorescence that might give off tips to issues.

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Looks like a decent re-pointing job (materials compatability aside.) And, it looks like a decent brick. If things look as nice close up as they do in this picture, I'd simply mention that re-pointing is a science, which if done wrong, can accelerate deterioration. You have no way of knowing how it was done. Feel free to shoot me closeup pics of any area that concerns you, John.

Thanks Mike. I'll be sure to post any concerns I find here at the forum.

So, does the correct softer mix of mortar typically have a lighter shade such as in this picture? How can the condition of the adjoining units affect this one?

John, this is where it gets a bit tricky. As I'm confident Bill will agree, if the brick is as hard as nails, then mortar hardness is far less of a concern. So start there. If the brick appears well fired (dark shades of red and very dense and hard), there probably isn't that high a potential for future damage, even if they did use a harder mortar. But, if the brick are poorly fired - lighter shades of red and porous/soft, then mortar compatiability becomes critical.

All of that aside, another more cosmetic tragedy in re-pointing is bringing the new mortar out flush to the face of the brick, if the brick edges have weathered (rounded). Doing this makes the joints appear fatter than they actually are , because of the rounded brick edges (simple geometry). If the bricks are weathered, you need to stop the mortar right where the weathering of the brick edge begins, and slick the surface right there. Make sense?

I understand what you're saying Mike. Just to be clear, bringing mortar out flush to the face over rounded edges as you mentioned, that's just a cosmetic issue, correct?

No. Actually, soft weathered brick with rounded edges pointed out to the face of the brick with excessively hard mort is the WORST possible combination. The wider cementicious joints act as a bit of a dam - preventing moisture from evaporting from the brick corners. This is preciesely what accelerates the deterioration, through freezing and expansion. THAT is the scenario that causes major brick face spalling - where the face is deeply receeded (deteriorated away).

Got it. It was because you said "cosmetic tragedy" in your previous post that had me asking to make sure. I understand that there are various combinations of right and wrong. The span can run from just fine to totally whacked. I'll just have to see what I find tomorrow.

It might be raining so I wonder if that would hide efflorescence that might give off tips to issues.

Nope, Efflorescence will still be apparent. Just remember - the softer the brick, the more mortar compatibility matters. You'll do fine. Looks like a nice home.

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I've seen some of the "flippers' peel the old brick face off and install new brick. From the photo, that might be what they did. I hate when they finish off those basements, you can't see anything and that's where I typically see the sand on the floor from the old soft mortar. What I've seen is where they have a proper height in a finished basement is that they have completely gutted the interior, left just the exterior and side walls, and then run new joists at a higher level. That's good because they didn't disturb the footings by digging down beside them but you really can't see too much about how they did the new framing. Typically, now when you go in the front door, there will be a step-up.

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Is there a way to tell by scratching a the mortar if it's softer like it should be or would recognizing that take an experienced mason or other?

It tastes like Tums.
Heh,

That reminds me. When I shone my flashlight on a bunch of rat droppings in the corner of a basement the other day the client asked me if I could tell if they were fresh. I answered, "Not really, but you're welcome to taste one if you think it will help you determine that."

He laughed but I'm not sure if he knew I was joking or thought I was serious.

ONE TEAM - ONE FIGHT!!!

Mike

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The type of mortar on the front of the house didn't concern me after all. It was very sandy like and not like portland based. In addition, the bricks were a newer variety and harder so the mortar type would be less of a concern.

This is not to say there were not concerns. The front walls were shifted in differentail movement above the lower window and bowed out all across the tops of the upper window lintels. Mortar joints at the lintels that were re-pointed were up to an inch thick to fill the gaps left by movement.

The adjoining units were both abandoned and dilapidated. Their roofs were totally shot. The soft bricks at the rear of the adjoining units were in terrible shape. The rear wall of the renovated unit has a stucco like panel pasted over the structural brick. I assume the brick was in such bad condition the decision was made to cover it up. That leaves alot of unanswered questions to be concerned about.

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That 4th pic is what I thought the brick would look like close up (wire-cut), simply based upon the color range from a distance. That had me wondering, with you original post as now, if those brick are original to the building. I don't think they were using those brick at the turn of the century. I think they showed up on the scene more like the 30s or 40s - Bill?

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That 4th pic is what I thought the brick would look like close up (wire-cut), simply based upon the color range from a distance. That had me wondering, with you original post as now, if those brick are original to the building. I don't think they were using those brick at the turn of the century. I think they showed up on the scene more like the 30s or 40s - Bill?

Correct. Compare the facade bricks to the bricks of the chimney. As Charlie stated, they were replaced.

When you start getting calls to inspect buildings like that, it's time to raise fees.

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That 4th pic is what I thought the brick would look like close up (wire-cut), simply based upon the color range from a distance. That had me wondering, with you original post as now, if those brick are original to the building. I don't think they were using those brick at the turn of the century. I think they showed up on the scene more like the 30s or 40s - Bill?

We call them "rug bricks" and I see them exclusively on buidings from the late '40 to the early '60s.

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