Will new mortar stick to old mortar?

Applying fresh mortar on top of old mortar that is loose or falling out will do little or no good; enough of the old mortar must be removed to make room for a layer of new mortar that is at least half an inch thick, and even then it is important to make sure that what is left of the old mortar is still solid and ...
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Do you have to remove old mortar before repointing?

The chisels will break the bond between the Portland-based mortar and the brick or stone. In repointing brick usually the repointed joints are less than an inch deep, so removal is safe as long as care is taken with the faces of the masonry units. Remove mortar at least 2x the height of the joint.
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How do you get mortar to stick to mortar?

Mix in powdered latex bonding agent, an additive commonly used to turn any type of mortar into a stickier, flexible finished product. The latex additive functions exactly like the premixed latex mortar, but you can vary its stickiness factor by changing the amount of latex you add to the mortar.
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Can you repoint over old mortar?

Can You Mortar Over Old Mortar? If your brick is 50 years old or less, you can probably repoint it safely with modern, portland cement–based mortar (although the guy doing the next repointing, who'll have to grind it out, may curse your decision).
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Can you mortar over mortar?

Applying fresh mortar on top of old mortar that is loose or falling out will do little or no good; enough of the old mortar must be removed to make room for a layer of new mortar that is at least half an inch thick, and even then it is important to make sure that what is left of the old mortar is still solid and ...
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Is Your Mortar weak And Crumbling?



Why does my mortar keep cracking?

Cracking can result from a variety of problems: differential settlement of foundations, drying shrinkage, expansion and contraction due to ambient thermal and moisture variations, improper support over openings, the effects of freeze-thaw cycles, the corrosion of iron and steel wall reinforcement, differential movement ...
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How do you fix crumbling mortar?

If the cracked mortar is harder, make a relief cut down the center of the mortar joint using the pointed edge of the chisel and then gently chip out the mortar (brick grout) that contacts the brick. If the removal work is going really slowly, use an angle grinder to make the relief cuts.
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How do you bond mortar to old concrete?

When using a liquid bonding agent, paint the bonder onto the existing concrete and allow it to dry until it is tacky. This usually takes only a few minutes. Then apply the repair material. After the bonder has become tacky, apply a scratch coat as described above and then apply the repair material.
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Why did my mortar not stick?

If the mortar is too dry, the block won't stick together properly. If it's too wet, runny mortar will overflow from the joints, leading to clean up that can waste time and material. Mix mortar from scratch by blending one part Portland cement to three parts sand.
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Why does my mortar not stick?

Why Won't My Mortar Stick? Most of the time this is a result of an incorrect ratio between cement and sand – if you have too much of the latter and not enough of the former, the adhesive effectiveness will be greatly reduced.
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Can you sand down mortar?

Use it to sand thinset the same way you would use a sandpaper-wrapped wooden block. First, sand up and down and then side to side using strong, even pressure. Wipe away the dust every few minutes, or use a hose attachment to vacuum it away.
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What depth should repointing be?

As a general rule, the pointing to be repaired must be dug out to a minimum depth of about two-and-a-half times its thickness, in other words ¾ inch to one inch for regular 3/8-inch pointing. You need to dig at least ¾ inch deep for thinner pointing.
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How do you know if mortar is bad?

If the mortar is loose, crumbling, or falls out easily with digging, it is in need of repair or restoration. Visually inspect the walls for a crumbling or flaking of the surface of their brickwork. This form of deterioration, known as spalling, usually results from some source of water damage.
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How do I strengthen my mortar mix?

To create the best mortar mix, add some volcanic ash that's high in silica content to the mix. I'd mix 1.5 parts sand, 0.5 parts volcanic ash to 1 part hydrated lime. Only mix as much mortar as can be applied in an hour. You never want to add more water to a mortar mix if the mortar starts to get hard.
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How thick should the mortar be between bricks?

The construction code for weight-bearing brick walls specifies that mortar be no thicker than 3/8 inch. According to the MC2 Estimator's Reference page, the thickness of mortar in different types of constructions can range from 1/8 inch to 3/4 inch.
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How long does it take mortar to harden?

Mortar typically will cure to 60% of its final compressive strength within the first 24 hours. It will then take about 28 days to reach its final cure strength. However the curing process does not always follow a universal timeline. There are a few key environmental variables that affect your mortar cure time.
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Are hairline cracks in mortar normal?

Hairline Cracks occur in the mortar between bricks or concrete blocks. Some hairline cracks are natural and usually no cause for alarm. Stair-Step Cracks look like stair steps in the home's mortar and may be a cause for concern if the cracks measure more than a 1/4 in width and the wall or foundation is bulging.
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How do I change the color of my existing mortar?

  1. Apply a 10 percent solution of muriatic acid to the mortar with a small paintbrush.
  2. Allow the acid to remain on the mortar for about five minutes or until the acid has stopped fizzing.
  3. Rinse the area and allow it to dry to see the color change.
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Does more cement make mortar darker?

In short, yes, the colour of the cement that used in a mortar mix does have an effect on its overall colour.
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Does mortar get lighter as Dries?

It looks awesome, I LOVE it. I know that the mortar is going to lighten up substantially when it dries. It will look good lighter too so I'm not worried I just want to know when I will see what it is actually going to look like.
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Will new thinset stick to old thinset?

You can put new thinset on top of old, but only if the old thinset is perfectly smooth and level. This is rarely the case once the old tiles have been removed. The best option to smooth out the old thinset and prepare it for new tiles is to grind it down.
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