Need help choosing correct cement mix for pointing

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Old 05-12-14, 03:36 PM
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Need help choosing correct cement mix for pointing

Hello everyone,

I'm an avid DIY'er and want to try to repoint some stones and bricks. The problem is I am not sure cement mix to use (cement, lime, etc.) for the stones. I also have some bricks that look like they haven't been repointed in a long time and would like a suggestion for what to use for the bricks as well.

Attached are some pictures. Thanks for your help.

Front and rear of house stones needing repointing:
[ATTACH=CONFIG]31582[/ATTACH]
[ATTACH=CONFIG]31584[/ATTACH]

Front bricks needing repointing:
[ATTACH=CONFIG]31583[/ATTACH]

What the neighbor had done about 6 years ago:
[ATTACH=CONFIG]31585[/ATTACH]
 
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Old 05-12-14, 04:37 PM
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You don't use a "cement" mix, you use a mortar mix. Cement is one of the component parts of concrete and mortar.

Someone that is competent with bricks and stone masonry will advise on the different mortars, how they are mixed and where they are used. It might take a day or two so don't give up. This is an all-volunteer board and most of the experts have day jobs to pay the bills.
 
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Old 05-13-14, 06:37 AM
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A general rule of thumb is that the mortar should be a similar mix to the original.
If the original is a lime mortar containing no OPC, then a lime mortar should be used. Mortar should normally be weaker than the masonry.
The mortar mix you use will therefore depend on the type of brick and stone as well as the climate.
The last photo shows raised ribbon pointing, which is not really ideal for a damp climate as it tends to trap moisture in the wall.
It also makes the eye see the mortar joints more than the stone, so does not look very good, although looks are a matter of opinion.
Most older buildings have the joints slightly recessed with a lime mortar to allow the walls to breathe.
 
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Old 05-13-14, 06:39 AM
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There are several types of mortar mix. Type N (800 psi) Type S (2000 psi) and Type M (3000 psi) compressive strengths. Type S and M are used for load bearing applications and Type N is used for pointing and ornamental.
 
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Old 05-13-14, 06:56 AM
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Just go to the local building materials place that sells cement and other masonry materials. Ask for a Type N mortar mix in a bag that includes the sand and cementitous materials. Mix according to the directions on the bag. - Start on a wall that is not obvious, since your skills will improve.

N is used on loadbearing structures, since the mortar strength is more than adequate. for building up to a few stories.

Dick
 
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Old 05-16-14, 05:09 PM
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Thanks. Would Type N be suitable for both the bricks and stone, or just the stone?

Also, can I use a mortar bag to apply Type N mortar? I've read online that some mortar is not compatible with using with mortar bags.

Thanks again.
 
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Old 05-30-14, 09:18 AM
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Hello everyone,

I'm still planning to do this. I went to the local home depot and they have the Type N mortar mix that I have to mix with the sand as well as the Veneer mortar mix, which had the information sheet that specifies Veneer mortar mix for stone pointing.

Would it be better to use the pre-mixed Veneer mortar mix or just go and buy the Type N + sand and mix according to the instructions?

Thanks.
 
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