Mortar is used between bricks, cinder blocks, or stone to bind them and fill any gaps. It is made from sand, a binding agent (cement or lime), and water.

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What actually happens if I vary proportions of cement and sand in mortar?

When preparing cement mortar proportions of sand and cement can AFAIK be varied. I've always been using the "default recommended" 1-to-3 (one volume of cement for every three volumes of sand) ...
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5answers
5k views

Why do builders say that wet concrete/mortar is not as strong?

I have been watching a few videos demonstrating the mixing of mortar and cement and a constant theme is that you must not have the mix too runny. I cannot fathom the reason... Does anyone care to ...
11
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3answers
20k views

What kind of mortar should I use to point a fieldstone foundation?

What kind of mortar should I use to point a fieldstone foundation? The old mortar is crumbling, and sandy mortar is falling out onto the basement floor. I plan to remove the crumbling mortar (see ...
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2answers
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Must I remove all mortar between tiles before grouting?

I'm just getting ready to lay down the grout after successfully tiling our master bathroom. I've been told in no uncertain terms that I must remove the spacers between tiles (or else grouting over ...
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1answer
248 views

Mortar (or something) falling out of basement brick wall

In my basement, there is a powdery, bright white substance between some of the bricks. It looks like it was something applied on top of the mortar joint. I scraped a couple places where it was falling ...
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2answers
717 views

Should I fill eroded mortar in exterior brick?

There's a few bricks around my house about 40cm up from ground level where the vertical mortar between the bricks has completely fallen out / eroded away. In a few spots, there's insects going into ...
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5answers
2k views

Do they make a non-liquid concrete/mortar color additive?

I've been trying to find a cement additive to change the color of some mortar, but only seem to be able to find it in liquid form at my local big-box hardware store. I'm looking for a similar ...
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3answers
609 views

Will colouring mortar weaken it?

My neighbour has recently had some work done to her roof. The old mortar was red and the new mortar is grey (uncoloured). So it looks a little silly with both colours present. She's not very happy ...
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3answers
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What thinset should I use?

I will be tiling a tub/shower area using 8x10 ceramic tile with glass mosaic tile accent rows. I see about half a dozen varieties of thin-set on the market: Weights: - 25lb - 50lb Types: - ...
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2answers
377 views

How can I stop mortar plugs from popping out of slab holes?

Our termite people plugged their dozens of chemical insertion holes using a regular grout. Needless to say the plugs are popping out left and right. (They tell me that is normal, the plugs pop out in ...
6
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1answer
571 views

What should I do about my concrete shower curb that I did not remove all the air bubbles from?

I'm building a concrete shower curb and pan. I built the curb and when I removed the 2x8 forms I notice that I didn't pack the cement all the way to the bottom in some parts: A bit crumbled and ...
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1answer
2k views

Should I supporting a load via anchors in brick or mortar?

I'm attempting to hang window flower boxes (a metal frame with a moss/fabric insert, filled with dirt/flowers/water for a total weight of about 15 lbs) on a brick wall. An example of a similar metal ...
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1answer
311 views

How to repair mortar that is crumbling?

The interior of my stone basement foundation wall has been mortared it is starting to sand off. What is the best way to seal it off so I can paint it again? The home was built in the 20's and has no ...
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1answer
2k views

How to fix a through hole in a concrete step?

Here're two photos of a through hole in a step in an enforced concrete staircase in an apartment building. The step is about one inch thick, the hole is about three inches wide and appeared many years ...
5
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1answer
188 views

Re-Pointing Fieldstone Foundation [duplicate]

I purchased my 110 year old colonial house 6 months ago. It has a field stone foundation that looks completely original (with a few small repairs). The house is located in North Eastern Massachusetts ...
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3answers
2k views

Contractor suggests caulking cracks in chimney, is that the right solution?

The mortar in our 25-year-old chimney is starting to crack and now leaks into our home if it rains hard. I assume we're probably in need of repointing, but a contractor that has done roof work for us ...
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1answer
5k views

What is the difference between building sand and plaster sand

Recently I mixed a batch of mortar for building and was unsure if the hardware provided me with building sand or plaster sand.. What are the properties that differentiate the two? and are there any ...
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2answers
3k views

How do I replace a bricked in mailbox?

My in-laws have a Mailbox that's a normal looking metal mailbox that's in a brick enclosure. It appears that when it was built, someone just put down mortar, set the mailbox in it, covered the ...
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1answer
389 views

What mix of cement and sand should I use to set cap slabs?

We have a number of "slabs" that are just wider than a brick, which are set on top of walls in the garden. A number of them have come lose and I need to remove the cement mix that used to hold them ...
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3answers
1k views

Is there some flexible cement-based mortar?

I live in an apartment in a multistoried building. The building is assembled of huge enforced concrete plates - one plate is size of a wall of a room. One of the inter-plate seams has a crack in it ...
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2answers
449 views

Mount an LCD TV to 30 year old masonry fireplace

Power and HDMI are no issue. I'm worried about messing with the mortar. Any advice? Will this be an issue, more trouble than it's worth, etc? I have some alternatives. Leave my TV on the mantle or ...
3
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1answer
540 views

Cause of eroded mortar in exterior brick

This question actually reminded me of an issue with my exterior walls. I have the same problem with the vertical mortar being eroded/missing from several bricks at ground level on the exterior of my ...
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1answer
518 views

How do I darken new mortar in a brick wall to match the older mortar?

I had some bricks replaced. Unfortunately, the mortar is really light. How do I stain it a darker gray, so that it matches the original mortar? Is there a product that I can buy at a big box store?
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1answer
530 views

The mortar between my patio bricks is crumbling away

The bricks on my front porch have some sort of mortar that crumbles away more and more every time I pull a weed from it. You could pick this stuff away with an awl but it is not just sand that you ...
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3answers
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What mortar should be used for flagstone?

I once read about a mortar that starts as a powder I could put in between my flagstones, and then just wet it down and it would harden in place. Do you know what this product is?
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2answers
677 views

Would replacing old mortar for new prevent water from seeping through brickwork?

Would replacing old mortar for new prevent water from seeping through brickwork? I have included photographs just in case this is a special case:
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1answer
382 views

What is the best way to uncover weeping holes?

We just bought a house where an old man lived for 27years. When he built the place, I doubt that he had any idea that the voids in the brick were weeping holes. I would like to fix them, but I'm not ...
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1answer
133 views

Will cement used as mortar need to be replaced?

I had some cracked/spalling bricks on my home as a result of water getting in and freezing during the winter. I went ahead and replaced five bricks (three on top and two below) and accidentally used ...
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1answer
300 views

What type of mortar should I use?

I'm going to replace these cracked bricks on the front of my home(see pic). What type of mortar should I use? Type S, N, or M? Is there a way to determine the type of mortar that was used when the ...
2
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1answer
75 views

Can a problem with heater stack liner cause outside chimney mortar to crack and fall out

I had "high-efficiency" furnace installed in 2009. In 2011 chimney required full grind-out and repoint job, and chimney saver solution was applied to prevent water damage. Service lasted only 18 ...
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0answers
133 views

How do I level a summerhouse concrete base that dips in the middle?

I laid a 4x3 metre concrete base for my summerhouse/office thing. The corners are all level and so the summerhouse sits fine, but it dips in between and so the load bearing battens aren't taking any ...
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2answers
4k views

How can I remove grout and mortar from a drain?

I accidentally poured some mortar and grout down my bathroom drain when I was cleaning the remains of a bucket of mortar after tiling the kitchen. The drain was plugged up pretty bad so I tried to ...
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2answers
698 views

Can I change the color of the mortar in my brick wall?

We recently built our home and the mortar color between the bricks is dark gray, we did not pay attention to it and because of that the brick face is looking duller due to the standard gray mortar. ...
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2answers
2k views

What is the best choice for patching and leveling concrete before tile install?

We have a small area of concrete foundation that we need to patch and level prior to ceramic tile installation (12×12 tiles). It is concrete that we chipped the old tile mortar off of, so there are ...
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2answers
11k views

What water:cement:sand ratio gives the strongest mortar?

A typical mortar mix ratio is 1 cement : 3 sand. But what is the water ratio? Is it 0.5:1:3? Would a 0.5:1:2 ratio be a stronger mortar? Our next door neighbor has a dog that digs like a pro. The ...
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1answer
510 views

What type of mortar would I use to seal cracks in our chimney?

We've got a brick chimney that's ~25 years old and it's got a quite a few cracks in the mortar (some hairline, some as thick is a quarter). What's the best way to seal all those cracks? I assume ...
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0answers
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Will I have any issues installing an in-floor heating mat with premix mortar?

I installed a radiant floor heating mat under ceramic tiles using a premix mortar. I now understand this was not the right thing to do. After further research the only reason I can find that suggests ...
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4answers
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How to reduce noise while drilling?

Unfortunately I can only drill in the late afternoon or during weekends, but my area is very quiet and I would really like to avoid driving my neighbours mad... So is there anything I can do to make ...
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1answer
28 views

Can unused mortar that freezes be used?

I left a bag of opened Porcelain mortar in the garage for a week and during that time the temperature got below freezing. Can I use this mortar or does it have to be thrown out?
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0answers
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What is a suitable mortar when repointing a wall made of soft red brick?

I am about to re-point the front of my Victorian (1895) house which has soft red bricks. Is a 4:1 ratio of sand to cement suitable? I have read that cement can force the moisture though the bricks ...
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0answers
39 views

How do I repair a field stone foundation on 99 year old house? [duplicate]

The foundation on our 99 year old house is made up of field stone and cement. Some patch jobs were done with cementing over the field stone. However that is breaking away and some other places have ...