# Cement-based Product Comparison Chart



## hellohello (Oct 17, 2013)

Does anyone know if there is a comparison chart available for cement-based products? I'd like it for reference, since I'm trying to learn a little bit more about masonry. For example, I'd like to know what is the difference between concrete, masons mix, sand/topping mix, modified thinset, unmodified thinset, stucco mix, scratch coat mix, etc. What is each composed of (i.e. sand, lime, portland cement, aggregate, etc), and how much of each? For example, sand/topping mix is sand and portland cement in a ratio of [insert ratio here], and masons mix is sand/topping mix with some lime in it in a ratio of [insert ratio here], etc. And then what's the product to water ratio of each mix?

I feel a chart would be REALLY handy for this, and make it easy to compare and contrast different cement-based products. So anyone have a link to one?


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## Tscarborough (Mar 31, 2006)

It would be handy, but there is no such thing, nor is one really possible in the format you want.

"Cement" is a term for an action, not a material, and can thus vary from cow milk to epoxy. What the material IS is not nearly as important as what you want to use it for.

For example, concrete and mortar can consist of the same things, i.e. portland cement, aggregate, and water, but they are not the same and the desired properties of the finished material are extremely different.

Since you can't define by name and you can't define by ingredients, the only thing left is to define by required physical properties. This is usually how materials are specified, although the goal of every manufacturer is to have their product specified by name even though it it may not be composed of any proprietary materials or methods.

For example, mortars are specified by their strengths: Type M(2500psi), S(1800psi), N(750psi), O(350psi), K(no strength, usually specified by mix design). This can be done in one of 2 ways, by PERFORMANCE or by PROPORTION. Google "mortar ASTM-C270" for more information.

All that said, here are some definitions of terms that cause problems when homeowners interact with professionals, because these terms mean specific things in the industry and are not really interchangeable.

Cement - Means nothing, don't use this word in speaking of masonry unless it is proceeded by another term.

Stucco - Means a system of cementious (or acrylic) wall coating. As with "cement", it is meaningless without modifiers specifying exactly what you are talking about.

Portland cement - There are 4 primary types, of which most people will ever only see one: Type I,II,III and H. Most Portland Cement sold in the US is Type I/II. It is used in many other products like concrete, mortar, thinset, etc.

Lime - Limestone is burnt, hydrated, and milled. In the US there are no natural hydraulic limes, only hydrated ones. For masonry, Type S is used.

Masonry Cement - It can be composed of Portland Cement and Lime, or masonry cement as a manufactured material that contains no Portland cement at all. It is designated by a strength, Type S or N, commonly. It is mixed with masonry sand to produce mortar.

Mortar - Masonry cement and sand, also designated by a Strength, Type S or N, commonly. Just add water.

Thinset - Mortar that is designed to be use in applications requiring a thin bed, hence "thinset". It may or may not include additives to increase the flexural, bonding and compressive strengths. There are various types designed for specific uses, i.e. "floor thinset" or "wall thinset" or "polymer-modified thinset".

Things like "topping mix", "parge coat", etc. do not really specify a particular material or mix, everyone has their own mix and it will vary with the specific job at hand.

Ratios of aggregate to cement, water to mortar, etc are not used in the industry except as a broad outline. Jobsite conditions vary enough that masons have to have latitude to adjust. For example, the Standard specification for mortar (ASTM C-270) gives the ratio for a 
Type N mortar like this:

1 part Portland cement, 1 part Type S lime and, 2-1/4 to 3 parts ASTM C-144 masonry sand (or it can be 1 part Masonry Cement and 2-1/4-3 parts ASTM C-144 masonry sand).

That is a difference of 25% aggregate allowable, pretty significant. Water is specified only to be potable and "provide a workable mortar".


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## concretemasonry (Oct 10, 2006)

On top of that it gets even more complicated for mortar.

The ASTM standard for mortar (ASTM 270) has comments includes in it that recommend to use the weakest mortar possible for the loads, because lower strength mortars have other properties (workability, water retentions, etc.) that make it more appropriate.

For structural purposes, mortar is NOT the major factor in the real strength of a wall. That is determined by a 2 block(hollow) prism that is face shell bedded. I have seen block prisms that had a strenth of 4800 psi made with 2200 psi mortar.

There is always the ages of question - "Does mortar hold masonry units together or keep them apart?"

Dick


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## Tscarborough (Mar 31, 2006)

Exactly. Remember that old Incan masonry with "joints so tight you can't stick a knife into it"? Well, they didn't do that because it looks cool or because they didn't want anyone sticking knives in their joints, they did it because with no mortar the bedding surfaces have to be exactly mated or the weight of the wall alone, acting on any minor imperfection, will crack the masonry.

That is why we use mortar. Unlike the Inca with infinite manpower and no concept of time, we need to use imperfect masonry units in an affordable and timely manner to construct our buildings. Mortar allows for the use of masonry units with allowable tolerances, and, in fact, joint size is designed to operate within those tolerances.


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## stadry (Jun 20, 2009)

i learned too,,, you're BOTH awesome :thumbup: GREAT replies !


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## Bondo (Dec 8, 2007)

Ayuh,.... Good read,.... I know just enough 'bout concrete products to be Dangerous,....

Startin' with a couple bags of Portland, you can get alota places,....


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