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PRODUCT NAME : Type N, Type S, Masonry Information and Type M MASONRY CEMENT: PRODUCT DATA SHEET MANUFACTURER Represented by: Association (PCA) 5420 Old Orchard Road Skokie, IL 60077-1083 Voice: 847.966.6200 Fax: 847.966.9781 Internet: www.cement.org

PRODUCT DESCRIPTION Basic Use: Masonry cement is spe- cially formulated and manufactured to produce masonry for use in , block, and stone masonry con- struction. Masonry are also used to produce . MORTAR AND MASONRY Masonry Cement The Crump Firm, architects on the Econocom-USA Corporate Headquarters Composition and Materials: Masonry Association PortlandCement cement consists of a mixture of portland Building, used masonry cement mortar in contrasting brick masonry panels to achieve a dramatic visual effect. cement or blended hydraulic cement and plasticizing materials (such as -

4 stone or hydrated or ), to- ing codes, and require- Physical Properties. Over the past gether with other materials introduced ments, should also be considered. sixty years, masonry cement has 2002 September to enhance one or more properties such Colors. Masonry cements are avail- become the masonry mortar material of as setting time, workability, water reten- able in a variety of colors as well as nat- choice for most masonry construction tion, and durability. These components ural gray. As an alternative to the use of in the United States because it provides are proportioned at the cement plant colored masonry cements, mineral ox- the basic advantages of consistent under controlled conditions to assure ide pigments may be added to the job workability, strength, color, and dura- uniformity of performance. site mixer to produce the color of mor- bility. This consistency of performance Types. Masonry cements are pro- tar desired. is assured by conformance to the phys- duced in Type N, Type S, and Type M Limitations. Masonry cements are de- ical property requirements for masonry strength levels for use in preparation of signed to be mixed with and water cements as listed in Table 2. ASTM Specification C270 Type N, S, or Masonry cement mortars provide an

September 2002 to produce a masonry mortar. The addi- M mortar, respectively, without further tion of hydrated lime to a masonry ce- excellent level of performance in the 4 addition of cements. ment mortar at the job site is not functional areas of workability, strength, Table 1 is a general guide for selec- required or recommended for conven- durability, and appearance that are so tion of mortar type. Other factors, such important to the mason, owner, and tional unit masonry construction. as type and absorption of masonry unit, designer. Portland Cement Portland Association

climate and exposure, applicable build- Workability. Workability is the Cement Masonry GROUT MASONRY AND MORTAR TECHNICAL DATA mason’s appraisal of the mortar’s ability Applicable Standards. Masonry to cling to head joints, slide smoothly Table 1. Recommended Guide for cements conform to ASTM C 91, the off the , and evenly support the Selection of Mortar Type Standard Specification for Masonry placement of units. Additionally, the Building Segment Type Cement. Masonry cements are used to mortar needs to retain these properties produce ASTM C 270 Type O, Type N, Exterior, above grade, for a reasonable length of time at what- load-bearing N or S Type S, and Type M mortars as outlined ever ambient conditions exist at the job non-load bearing N in either the property specification or site. That length of time that the mortar parapet N or S the proportion specification require- retains its workability is often termed its Exterior, at or below ments of ASTM C 270. Requirements grade S or M board life. The plasticizers contained in Interior for sand to be used with masonry ce- masonry cements contribute to their load-bearing N or S ment to produce ASTM C 270 mortars excellent workability, board life, and non-load bearing N are found in ASTM C 144. water retention. The importance of workability is apparent when one con- Table 2. Physical Properties of Masonry Cements (ASTM C 91) siders that workmanship is a key ele- Mortar Cement Type N S M ment in achieving quality masonry con- struction. Fineness, residue on a 45-µm (No. 325) sieve, maximum % 24 24 24 Strength. By simplifying mortar Autoclave expansion, materials batching at the job site, the maximum, % 1.0 1.0 1.0 use of masonry cement assures consis- Time of Setting tent strengths between batches and Initial Set, minimum, hr. 2 11⁄2 11⁄2 Final Set, maximum hr. 24 24 24 jobs. Masonry cement mortars prepared Compressive strength minimum, MPa (psi) according to the property requirements 7 days 3.4 (500) 9.0 (1300) 12.4 (1800) of ASTM C 270 provide compressive 28 day 6.2 (900) 14.5 (2100) 20.0 (2900) strengths that exceed the values listed Air content, volume, % in Table 3. High Strength Type S and Minimum 8 8 8 Maximum 21 19 19 Type M masonry cements allow the Water retention, flow after specifier to accommodate special suction as % of original flow application requirements related to Minimum 70 70 70 load bearing masonry, masonry below grade level, and masonry for paving without compromising the advantages Table 3. Physical Properties of Masonry Cement Mortars (ASTM C 270) of simplified batching. Compressive Strength Water Retention Air Content In addition to compressive strength, Mortar Type Minimum, MPa (psi) Minimum, % Maximum, % bond strength is also an important con- M 17.2 (2500) 75 18 sideration in masonry construction. S 12.4 (1800) 75 18 There are many factors that affect the N 5.2 (750) 75 20* bond of mortar to unit in actual con- O 2.4 (350) 75 20* struction, including properties of the *When structural reinforcement is incorporated in masonry cement mortar, the maximum air content unit and mortar, ambient conditions, shall be 18%. and the quality of workmanship in- volved. Masonry cement mortars pro- vide the mason with a highly excellent flexural bond strengths. provide effective resistance to freeze- mortar which readily flows into the sur- Seventy-five percent of these masonry thaw deterioration in masonry mortars. face irregularities of the unit, assuring cement mortars tested with a brick unit Masonry cement mortars have greater that the bond strength potential of the having an IRA of 9 g/min·194 cm2 (9 resistance to freeze-thaw deterioration materials is realized in the field when g/m·30 in2) yielded flexural bond than non-air-entrained-portland cement- combined with good workmanship. In strengths in excess of 690 kPa (100 psi). lime mortars. This superior performance an extensive laboratory study of over 20 None of these masonry cement mortars can be attributed to the controlled air different masonry cements representing produced values lower than 450 kPa content of masonry cement mortars. a cross section of producers throughout (65 psi). Several factors influence drying the United States, Ribar and Dubovoy1 Durability. Properties of masonry shrinkage of masonry mortars, includ- confirmed that masonry cements yield mortar related to its durability include: ing water content, rate of drying, sand • Resistance to freeze thaw deteriora- properties, moisture content and ab- tion, sorption of the masonry units, and ce- • Drying shrinkage characteristics, 0.14 mentitious material properties. Results • Resistance to sulfate attack, of laboratory tests shown in Fig. 1 indi- 0.12 • Water absorption characteristics, 0.1 and • Soundness 1 Dubovoy, V. S., and Ribar, J. W., Masonry 0.08 Masonry cement mortars provide Cement Mortars-A Laboratory Investigation, 0.06 significant performance advantages in Research and Development Bulletin RD095, Portland PCA, Skokie, IL, 1990, 26pp. these important areas. 2 Percent Shrinkage 0.04 Cement/ Davison, J. I., “Effect of Air Entrainment on Dur- The ability to endure the extremes of ability of Cement-Lime Mortars,” Durability of 0.02 repeated freeze-thaw cycles without Building Materials, Elsevier Publishing Co., 0 Masonry deterioration is critical to the long-term Amsterdam, 1981. 3 Type N Type S Cement Mortar 2,3 Zamatis, W. L., “Factors Affecting Performance performance of mortar. Research of Unit Masonry Mortar,” ACI Journal, Proc. Fig. 1 – Drying shrinkage of masonry shows that air entrainment levels of at Vol. 56, No. 6, American Institute, mortars at 28 days. least 10 to 12 percent are needed to Detroit, 1959. 0.4

0.35

0.4 0.3

0.35 0.25 0.3 0.2 0.25

Grams of Water 0.15 0.2 0.1 0.15 0.05 Length Change, % 0.1 P CL-N Masonry Portland P 0.05 C Portland Cement Cement/Lime L-S MC Cement/Lime -N 0 MC Fig. 3 – Water absorption of mortars. - 1384321 S Masonry Cement Age, weeks batching, it is easier to achieve a con- Fig. 2 – Sulfate expansion of masonry mortars. sistent appearance in the finished job when using masonry cements. Colored cate that the drying shrinkage of mason- masonry is susceptible to water pene- masonry cements are also available to ry cement mortars is about half that of tration and that the design and detail of match, contrast, or complement the portland cement-lime mortars. the masonry construction must accom- masonry units and enhance the archi- When sulfates come in contact with modate this fact. Important workman- tectural effect of the masonry. masonry mortar, subsequent expansion ship factors include achieving full head can cause deterioration of the mortar. and bed joints, following proper tooling INSTALLATION Thus resistance to sulfate expansion techniques, careful installation of flash- Preparation. Masonry cement mortar should be considered where seawater ing and weepholes, and maintaining materials mixed according to the pro- or sulfate-bearing soils come in contact clean cavities. The excellent workabili- portion specifications of ASTM C 270 with masonry mortar. Masonry cement ty, strength, and durability of masonry should be accurately proportioned as mortars demonstrate significantly cement mortars assure that the design- indicated in Table 4. Under the property greater sulfate resistance than portland ers’ and masons’ needs are met in requirements of ASTM C 270, sand-to- cement-lime mortars (see Fig. 2). regard to achieving watertight masonry cement proportions for the job-mixed Mortar can better resist chemical construction. Careful laboratory re- mortar are the same as those established attack, staining, and freeze-thaw - search has confirmed the excellent per- by laboratory tests of the mortar. The age if it is less absorbent. Tests shown in formance of masonry cement mortars in ratio of sand to cement is to be in the Fig. 3 indicate that masonry cement water permeance tests. These laborato- range of 21⁄4:1 to 31⁄2:1 by volume. mortars absorb only about half as much ry tests are backed up with a record of mixing should be used water as a comparable non-air en- over sixty years of excellent field per- whenever possible. First, with mixer trained portland cement-lime mortar. formance. running, add most of the water and half Expansion of mortars due to un- Appearance. The color of masonry of the sand required. Next, add the sound ingredients can cause serious de- mortar is a crucial component in the masonry cement and the balance of terioration of masonry. Soundness of a appearance of a masonry wall. Since sand. After one minute of continuous cementitious material is measured by masonry cement color is laboratory mixing, slowly add the rest of the water. the autoclave expansion test. This test controlled and masonry cement offers Mixing should continue for at least 3 produces reactions in any unsound the simplicity of the one-bag system of minutes. Extending the mixing time up ingredient and simulates a long period of exposure for the cementitious mate- rial. Conformance of masonry cement Table 4. ASTM C 270 Proportion Specification Requirements for Masonry Cement Mortars to the autoclave expansion limits of ASTM C 91 assures that there will be no Mortar Portland or Mortar Cement Type significant expansion of hardened mor- Type Blended Cement M S N Sand tar in a wall due to unsoundness. M —- 1 —- —- 21⁄4 - 3 1 Water Permeance. Water perme- M 1 —- —- 1 4 ⁄2 - 6 S—-—-1—-21⁄4 - 3 ance of masonry is primarily related to S 1⁄2 —- —- 1 33⁄8 - 41⁄2 workmanship and design. It is generally N—-—-—-121⁄4 - 3 recognized that a single wythe of O—-—-—-121⁄4 - 3 to 5 minutes improves the workability MAINTENANCE and water retentivity of the mortar. In Avoid use of harsh chemical clean- mixing, use as much water as practical ers or strong acid solutions in cleaning without impairing the workability of the masonry (refer to Installation). mortar. Application. The practice of good TECHNICAL SERVICES workmanship principles is required for Technical information and services successful application. This includes are available from PCA and member proper filling of head and bed joints, manufacturers. careful placement of units, appropriate The following related publications tooling of the joint, modification of are also available from PCA: construction procedures and/or sched- ules to adapt to extreme weather condi- Masonry Mortars – IS040 tions,4,5 and proper cleaning6 proce- Masonry Cement Mortars – IS181 dures. Good workmanship coupled Trowel Tips: Hot Weather Masonry with proper detailing and design Mortar – IS243 assures functional, durable, watertight Trowel Tips: Cleaning Masonry – IS244 masonry construction. William Wardlaw Center, Georgia Fresh mortar should be prepared at Institute of —Architect: Trowel Tips: Cold Weather Masonry the rate it is used, so that it does not Jova/Daniels/Busby, Inc. Mortar – IS248 stiffen in mortar boxes and on mortar- Selecting and Specifying Mortar and boards. If necessary to restore workabil- Grout for Unit Masonry – IS275 ity, mortar should be retempered by Quality Assurance for Masonry adding water and remixing thoroughly. Mortar – IS279 While the addition of water reduces the mortar joint surface must be avoid- Concrete Masonry Handbook – EB008 mortar strength slightly, this effect is ed. Follow the instructions of the man- preferable to the poor contact between ufacturer of the cleaning solution in its Recommended Practices for Laying brick and mortar that will result from application on trial cleaning of incon- Concrete Block – PA043 1 using dry, stiff mortar. Mortar over 2 ⁄2 spicuous areas to assure proper selec- hours old should not be retempered or tion of method and solution. Cleaning used. It should be discarded and with chemical solutions should not be replaced with freshly mixed mortar. attempted until the mortar has thor- Emphasis should be placed in oughly cured. Generally, about two masonry construction on minimizing the amount of cleaning required. weeks’ curing is recommended. Precautions to minimize the amount of mortar splatter that is left on a wall AVAILABILITY include: the practice of good basic Availability: Masonry cements are workmanship, dry brushing the face of regionally available in the United States the masonry wall after tooling with a and Canada from a network of dealers soft bristle brush, and turning back the and distributors representing PCA mem- inside scaffold board at the end of the ber producers. For a complete list of day to avoid rain splatter of mortar PCA member masonry cement manu- droppings from the board getting on the facturers contact PCA headquarters at wall. Such mortar protrusions and splat- 847. 966.6200, by fax at 847.966.9781, ters as occur should be removed before or at the Web site: www.cement.org. they tenaciously adhere to the masonry surface (preferably the morning after CERTIFICATION 4 Trowel Tips: Hot Weather Masonry Construc- laying) using stiff nonmetallic brushes, tion, IS243, PCA, Skokie, IL. nonmetallic scrapers, burlap, rags, or Masonry cement meets the require- 5 Trowel Tips: Cold Weather Masonry Construc- other appropriate means of removal. ments of ASTM C 91, The Standard tion, IS248, PCA Skokie, IL. 6 If, despite efforts to maintain clean Specification for Masonry Cement, for Trowel Tips: Cleaning Masonry, IS244, PCA, Skokie, IL. masonry during construction, it is felt the type specified. Written manufactur- that the use of masonry cleaning solu- er’s certifications to that effect may be tions are required, selection of cleaning obtained from PCA member company technique and solution should be com- producers of masonry cement upon patible with the units, and damage to request. IS282.03