Apply the grout with a rubber grout float, filling the joints over a 5- to 10-square-foot … (13 mm) must be removed from the masonry walls, reinforcement and foundation or bearing surface. Chip out the old cinder block and mortar. Break the stones along a specific line. 3) offers an additional option: to increase the grout lift height to 12 ft-8 in. See the Grout Demonstration Panel section of this TEK for further information. Use a similar motion on inside corners. Mix mortar and water, according to the instructions on the package. Masons installing grout in CMU voids Grout specifications are governed by ASTM C476 Standard Specification for Grout for Masonry , which provides the proportions of materials to be used. Press the first block, a corner block, into the mortar. Block Wall Thickness. This is because large protrusions can restrict the flow of grout, which will tend to bridge at these locations potentially causing incomplete filling of the grout space. However, it is required that both horizontal and vertical reinforcement be located within tolerances and secured to prevent displacement during grouting (ref. By filling the cracks and the surrounding voids inside the wall, the wall strength is restored and the adjacent mortar has not been disturbed. Pilaster and column units are used to accommodate a wall- column or wall-pilaster interface, allowing space for vertical reinforcement and ties, if necessary, in the hollow center. When all cores, with or without reinforcement, are grouted, the wall is considered solidly grouted. These advances permit more efficient installation and construction options for grouted concrete masonry walls (see Figure 4). For higher pour heights, mechanical vibration is required and reconsolidation is also required. Steel reinforcing bars and other embedded items are then placed in the designated locations and the cells are grouted. When grout comes up out of a hole 2 feet above the point where it is … This TEK covers methods for laying the units, placing steel reinforcement and grouting. Face shells are removed either by cutting or use of special scored units which permit easy removal of part of the face shell for cleanout openings (see Figure 5). Disclaimer: Although care has been taken to ensure the enclosed information is as accurate and complete as possible, NCMA does not assume responsibility for errors or omissions resulting from the use of this TEK. Specification for Masonry Structures, ACI 530.1-02/ ASCE 6-02/TMS 602-02. If you have questions about specific products or services we provide, please don’t hesitate to contact us. Add an anti-freezing agent if the frame is being used in an exterior opening. 3) is an excellent way to demonstrate the acceptability of an alternate grout slump. Chip out the mortar, then brush away any additional dust or debris … Spread the cement on the wall in in upward motion, then finish with a circular motion over the same area. In certain instances, full head joint mortaring should also be considered when solid grouting since it is unlikely that grout will fill the space between head joints that are only mortared the width of the face shell, i.e., when penetration resistance is a concern such as storm shelters and prison walls. Mortar that projects more than ½ in. If conditions permit and grout pours are so timed, consolidation of a lift and reconsolidation of the lift below may be done at the same time by extending the vibrator through the top lift and into the one below. Block Wall (Grout) Calculator. Skim coating takes time and attention to detail, but isn't inherently difficult. With the advent of self-consolidating grouts and other innovative consolidation techniques, this provision of the Specification has been very useful in demonstrating the effectiveness of alternate grouting procedures to the architect/engineer and building official. Approval should be obtained before adjusting the slump outside the requirements. Spread the grout. The industry is experiencing fast-paced advances in grouting procedures and materials as building codes allow new opportunities to explore means and methods for constructing grouted masonry walls. When walls will be grouted, concrete masonry units must be laid up so that vertical cores are aligned to form an unobstructed, continuous series of vertical spaces within the wall. A common way to improve the thermal performance of those walls … Historically, only two grout placement procedures have been in general use: (l) where the wall is constructed to pour heights up to 5 ft (1,520 mm) without cleanouts—generally termed “low lift grouting;” and (2) where the wall is constructed to a maximum pour height of 24 ft (7,320 mm) with required cleanouts and lifts are placed in increments of 5 ft (1,520 mm)—generally termed “high lift grouting.” With the advent of the 2002 Specification for Masonry Structures (ref. Less reinforcement is used for splices and the location of the reinforcement can be easily checked by the inspector prior to grouting. Move any indoor or outdoor furniture away from the wall or cover it with plastic sheeting if it must remain near the wall. Seen info on whitewash or liming and the idea of sand washing, using cement, sand and paint. Load the joints. Standard two-core concrete masonry units can be effectively reinforced when lap splices are not long, since the mason must lift the units over any vertical reinforcing bars that extend above the previously installed masonry. (203 to 279 mm) (refs. See the section titled Consolidation and Reconsolidation in this TEK. When reinforcement is placed after wall erection, reinforcing steel positioners or other adequate devices to hold the reinforcement in place are commonly used, but not required. Grout is to be placed within 1 ½ hours from the initial introduction of water and prior to initial set (ref. An important factor mentioned in both grouting procedures is consolidation. Concrete masonry units should meet applicable ASTM standards and should typically be stored on pallets to prevent excessive dirt and water from contaminating the units. What Is the Minimum Thickness of Cement Board When Tiling Walls? Cleanout openings must be made in the face shells of the bottom course of units at the location of the grout pour. Home | Online Tools | Block Wall (Grout) Calculator. As the masonry is installed around the frame, pour or trowel a small amount of grout into the frame. 5), a third option became available – grout demonstration panels. Reconsolidation acts to remove these small voids and should generally be done between 3 and 10 minutes after grout placement. 3) requires a minimum opening dimension of 3 in. Reinforcing bars must be of the specified diameter, type and grade to assure compliance with the contract documents. If the wall will be solidly grouted, the cross webs need not be mortared since the grout flows laterally, filling all spaces. (3,860 mm) under the following conditions: Through the use of a grout demonstration panel, lift heights in excess of the 12 ft-8 in. The 2005 Specification for Masonry Structures (ref. A lift is the amount of grout placed in a single continuous operation. He holds a Bachelor of Arts in history and journalism from the University of Nebraska-Omaha. Grind down parts of the concrete blocks if necessary, and then use a hammer and chisel to knock away anything remaining. Cover landscaping, grass or flooring with plastic drop cloths. Bracing Concrete Masonry Walls During Construction. Grout must be consolidated either by vibration or puddling immediately after placement to help ensure complete filling of the grout space. When double open- end units are used, one cell is considered to be formed by the two open ends placed together. Cleanout openings may be sealed by mortaring the original face shell or section of face shell, or by blocking the openings to allow grouting to the finish plane of the wall. The pilasters could be tied to the existing block wall by knocking holes in the existing block and grouting in anchor bolts, or by tying reinforcing rods to the reinforcement in the new pilaster. If a dowel interferes with the placement of the units, it may be bent a maximum of 1 in. (Note that in Table 1, the maximum area of vertical reinforcement does not include the area at lap splices.) 1). Building Code Requirements for Masonry Structures, ACI 530-05/ASCE 5-05/TMS 402-05. Care should be taken to minimize grout splatter on reinforcement, on finished masonry unit faces or into cores not immediately being grouted. How to Repair Cracked Mortar On an Exterior Brick Wall. Except in markets with seismic or high wind activity, building codes allow structural CMU walls for single-family, single-level homes to be left partially or completely unfilled with grout. SPEC MIX Core Fill Grout is produced under strict manufacturing standards, and complete quality control measures are implemented with each batch. All-Weather Concrete Masonry Construction. (203 mm) per Building Code Requirements for Masonry Structures (ref. Follow the manufacturer's instructions. Meets and exceeds the performance requirements of ASTM C476 for masonry grouts. The consistency should be a thick paste. If vertical reinforcement is spaced close together and/or there are a significant number of bond beams within the wall, it may be faster and more economical to solidly grout the wall. The vibrator should be withdrawn slowly enough while on to allow the grout to close up the space that was occupied by the vibrator. As the wall is constructed, horizontal reinforcement can be placed in bond beam or lintel units. This provision accommodates construction interference during installation as well as misplaced dowels. Horizontal reinforcement in concrete masonry walls can be accommodated either by saw-cutting webs out of a standard unit or by using bond beam units. 3). Smear the grout diagonally across the tile to force it deep into the … The length of lap splices should be shown on the project drawings. Mud, oil, heavy rust and other materials which adversely affect bond must be removed however. Use the trowel to scoop cement out of the bucket and onto the trowel. Using the grout demonstration panel option in Specification for Masonry Structures (ref. It is important to reconsolidate after the initial absorption has taken place and before the grout loses its plasticity. Grouted masonry requires special consideration because of the higher water content and potential disruptive expansion that can occur if that water freezes. (19 to 25 mm) head. Noncontact lap splices may be spaced as far apart as one-fifth the required length of the lap but not more than 8 in. A pour may be composed of one lift or a number of successively placed grout lifts, as illustrated in Figure 4. Grout demonstration panels have been used to allow placement of a significant amount of a relatively new product called self-consolidating grout to be used in many parts of the country with outstanding results. He now writes for the web as well. 14) contains a relationship between masonry bed joint shear strength measured in situ to the overall strength of a masonry shear wall. Work on one course at a time to keep pace with the block work. Fill in the following fields and submit and we'll get right on it. The concrete masonry units illustrated in Figure 3 are examples of shapes that have been developed specifically to accommodate reinforcement. (152 mm) vertically (see Figure 2). If each block has two voids then multiply the number of blocks by 2 to get the number of voids in the wall. Different mixes of fine grout were tried using different admixtures. A pour is the entire height of masonry to be grouted prior to the construction of additional masonry. Construction and approval of a grout demonstration panel using the proposed grouting procedures, construction techniques and grout space geometry is required. A concrete block wall, whether outdoors or otherwise, can suffer damage due to weather, flooding, or accident. Written approval is also required. The primary structural reinforcement used in concrete masonry is deformed steel bars. Pump a fluid grout into the core in 2-foot lifts from the bottom. National Concrete Masonry Association, 2004. One advantage is that a larger volume of grout can be placed at one time, thereby increasing the overall speed of construction. Roofing felt or materials that break the bond between the masonry units and mortar should not be used for grout stops. It is also used to fill bond beams and occasionally to fill the collar joint of a multi-wythe wall. Reinforcement can be spliced by either contact or noncontact splices. Using SPEC MIX Core Fill Grout in conjunction with existing reinforcement will produce a structurally sound final wall system for reinforced masonry construction. Remove the block in chunks as you free each piece from the surrounding mortar. (305 to 406 mm) apart. The timing depends on the water absorption rate, which varies with such factors as temperature, absorptive properties of the masonry units and the presence of water repellent admixtures in the units. Applied 1/8 inch thick minimum to both sides, surface bonding cements have strengths that are superior to conventionally mortared block walls and they look a lot better too without any grout lines. 7) for further information. When using the increased grout lift height provided for in Article 3.5 D of Specification for Masonry Structures (ref 3), the masonry is required to cure for a minimum of 4 hours prior to grouting for this reason. Splices are not required to be tied, however tying is often used as a means to hold bars in place. Tip 2 – Know what joint size you’ll need for your tile shower or glass block walls– Most tile shower walls and glass blocks will use joints greater than or equal to 1/8”. Use the flat side of the trowel to smooth the cement. This slump may be adjusted under certain conditions such as hot or cold weather installation, low absorption units or other project specific conditions. QUIKRETE® Core-Fill Grout (No. 3). See Steel Reinforcement for Concrete Masonry, TEK 12-4D for more information (ref. Specifications for grout, sampling and testing procedures, and information on admixtures are covered in NCMA TEK 9-4A, Grout for Concrete Masonry (ref. With the installation of cleanouts this can be done. Length - ft. He wrote news, sports and feature stories for the "Omaha World-Herald" and other publications and has continued on in direct marketing and general advertising. Vertical reinforcing steel may be placed before the blocks are laid, or after laying is completed. Cleanout openings may be sealed by mortaring the original face shell or section of face shell, or by blocking the openings to allow grouting to the finish plane of the wall. Scrape the wall with a drywall knife to remove loose cement or grout. The units may also need to be covered to protect them from rain and snow. As the water from the grout mixture is absorbed into the masonry, small voids may form and the grout column may settle. Fill the trowel about halfway with cement. Specification for Masonry Structures (ref. Figure 1 shows the basic components of a typical reinforced concrete masonry wall. The design of reinforced concrete masonry pilasters is discussed in NCMA-TEK 125. If foundation dowels are present, they should align with the cores of the masonry units. Be careful to create a 3/8-inch mortar joint on its underside. 8) has demonstrated adequate consolidation by vibrating the top 8 ft (2,440 mm) of a grout lift, relying on head pressure to consolidate the grout below. Cut stones to fit a specific area, using a hammer and chisel. If the wall will not be solidly grouted, the grout may be confined within the desired grout area either by using solid bottom masonry bond beam units or by placing plastic or metal screening, expanded metal lath or other approved material in the horizontal bed joint before laying the mortar and units being used to construct the bond beam. © 2020 NATIONAL CONCRETE MASONRY ASSOCIATION. use a jointer to recess the joints. On occasion there may be locations in the structure where splices are prohibited. Contractors elect to fill the hollow openings or voids in concrete blocks (sometimes referred to as grouting) after they are stacked or laid to achieve a stronger wall, one with properties nearly identical to a poured concrete wall. (305 mm) or less. Readily available materials can fix some cracking in a block wall without having to tear it down and add new concrete. Those locations are to be clearly marked on the drawing. To understand grout placement, the difference between a grout lift and a grout pour needs to be understood. Remove excess cement with the edge of the trowel, using a scraping motion. At flashing where reduced thickness units are used as shown in Figure 1, the exterior unit can be left out until after the masonry wall is laid up. Skim coating can freshen up old concrete blocks and give your home or a wall on your property a new look. 2, 3) at the time of placement. Grout may also be used to stabilize screen walls and other landscape elements. (3,860 mm) limitation may be permitted if the results of the demonstration show that the completed grout installation is not adversely affected. Concrete Block Wall Grout Filling in the radius. After laying masonry units, mortar droppings and projections larger than ½ in. In cases such as those, open end or open core units (see Figure 3) should be considered as there is no space between end webs with these types of units. (813 mm) on center (horizontal measurement) for solidly grouted walls. The top lift is reconsolidated after the required waiting period and then filled with grout to replace any void left by settlement. Research has demonstrated comparable or superior performance when compared with consolidated and reconsolidated conventional grout in regard to reduction of voids, compressive strength and bond to masonry face shells. Grout is used to give added strength to both reinforced and unreinforced concrete masonry walls by grouting either some or all of the cores. In reinforced masonry, grout bonds the masonry units and reinforcing steel so that they act together to resist imposed loads. Repeat steps 6 and 7, adjusting the blocks to be flush and level; continue this process until the first … If there is a substantial dowel alignment problem, the project engineer must be notified. Many times it is advantageous to build the masonry wall to full height before grouting rather than building it in 5 ft (1,520 mm) increments as described above. Head and bed joints must be filled with mortar for the full thickness of the face shell. 6). The interior side of the core can be formed using a piece of plywood held in place against the wall with masonry screws. I've installed grout stop over the unreinforced vertical cells. When installing glass block windows with mortar, use a damp cloth to clean any stray mortar or residue off the faces of the block. This “pencil head” vibrator is activated for a few seconds in each grouted cell. This eliminates the need to thread units over the top of the reinforcing bar. Larger quantities should be placed by grout pumps, grout buckets equipped with chutes or other mechanical means designed to move large volumes of grout without segregation. Hollow block prisms, 11/2 blocks wide by 4 courses high, were grouted from the sides using hand pump. The dimensions and weights (including heights of deformations) of a cleaned bar cannot be less than those required by the ASTM specification. Not sure if I look for a mason or a painter to do this work for my project. Height - ft. My foundation stem wall for a raised-floor house is four courses high, made of 8x8x16 concrete blocks with #4 vertical rebars every 4 feet and a #5 rebar in the bond beam top course. When the cleanout opening is to be exposed in the finished wall, it may be desirable to remove the entire face shell of the unit, so that it may be replaced in whole to better conceal the opening. (25 mm) below the top bed joint to help provide some mechanical keying action and water penetration resistance. The wall is built to scaffold height or to a bond beam course, to a maximum of 5 ft (1,520 mm). Apply 1/8 to 1/2 inch of cement, or enough to cover the grout. Another use for grout is to add mass to a block wall to reduce sound transmission or improve the thermal mass of the wall. Start at the top of the wall, near a corner. Face shell plugs should be adequately braced to resist fluid grout pressure. Looking for advice on how to re-grout an interior existing brick wall. 9). Laps are made at the end of grout pours and any time the bar has to be spliced. Guidelines for the Rehabilitation of Existing Buildings (ref. To prevent bridging, grout slump is required to be between 8 and 11 in. to 1 in. Read the directions on the sanded grout bag first. Specification for Masonry Structures, ACI 530.1-05/ ASCE 6-05/TMS 602-05. Total Cubic Yards. A second advantage is that high-lift grouting can permit constructing masonry to the full story height before placing vertical reinforcement and grout. To determine the width of your future wall, decide how many cinder blocks you want to use for the wall width, then calculate the width using the block's measurements. Protection is required when the minimum daily temperature during construction of grouted masonry is o o expected to fall below 40 F (4.4 C). Repeat the above steps until you’ve completed the wall. Small amounts of grout can be placed by hand with buckets. Use a hammer drill with a 10-millimeter masonry bit to clean up the gap in the wall so the lintel can be smoothly inserted. 4). Therefore, grouted masonry requires protection for longer periods than ungrouted masonry to allow the water to dissipate. (25 mm) horizontally for every 6 in. Reported by the Masonry Standards Joint Committee, 2005. aesthetically satisfactory repair of such cracks can be accomplished by the injection of fine grout into the wall at the vicinity of the cracks. Matt Smolsky has been writing for more than 25 years. Excess vibration may blow out the face shells or may separate wythes when grouting between wythes and can also cause grout segregation. Care should be taken to prevent excess mortar from extruding into the grout space. Further, this is needed only when a cold joint is formed between the lifts and only in areas that will be receiving additional grout. Mix the Portland cement in a bucket, using an electric drill and a mixing bit. When walls will be solidly grouted, saw cutting or chipping away a portion of the web to better accommodate the dowel may also be acceptable. Grout is a mixture of: cementitious material (usually portland cement); aggregate; enough water to cause the mixture to flow readily and without segregation into cores or cavities in the masonry; and sometimes admixtures. Face shell plugs should be adequately braced to resist fluid grout pressure. the masonry has cured for at least 4 hours, grout slump is maintained between 10 and 11 in. You will need sanded grout, a plastic bucket to mix it in, a stir stick, rubber or latex gloves, a masonry sponge, water and an offset spatula or grout trowel. If reinforcement is placed prior to laying block, the use of open-end A or H- shaped units will allow the units to be easily placed around the reinforcing steel (see Figure 3). See Bracing Concrete Masonry Walls During Construction, TEK 3-4C (ref. How to Fix Corner Bead That's Separating From Drywall, How Get Self-Stick Vinyl Tile to Stick to Walls, How to Make Cutouts Through a Concrete Wall, YouTube: Kirk Giordano Plastering, How to Skim Coat Over Cinder Block Walls, ConcreteNework.com: Tools for Applying Cement-Based Overlays, How to Make Perfect Corners for Sheetrock Walls. For more detailed information on cold, hot, and wet weather protection, see All-Weather Concrete Masonry Construction, TEK 3-1C (ref. Grouted concrete masonry construction offers design flexibility through the use of partially or fully grouted walls, whether plain or reinforced. ; Allow the mortar to cure and settle into the glass block for 24 to 48 hours. Keep the cement moist with a spray bottle as you use a smoothing paddle to smooth out any uneven spots. © Copyright 2020 Hearst Communications, Inc. The openings must be large enough to allow debris to be removed from the space to be grouted. High lift grouting offers certain advantages, especially on larger projects. The process involves applying a layer of cement over the concrete block wall to cover grout lines or stains and give the surface a smooth appearance. Recess the Joints. Puddling is allowed for grout pours of 12 in. Reported by the Masonry Standards Joint Committee, 2002. The grout spaces should be checked by the inspector for cleanliness and reinforcement position before the cleanouts are closed. Bond beam units are manufactured with either reduced webs or with “knock-out” webs, which are removed prior to placement in the wall. Investigation of Alternative Grouting Procedures in Concrete Masonry Construction Through Physical Evaluation and Quality Assessment, MR 25. (76 mm). You can also call … Without grout, you’re relying on gravity and your mortar to keep the wall intact. Grout installation without cleanouts is sometimes called low-lift grouting. Cleanouts must be located at the bottom of all cores containing dowels or vertical reinforcement and at a maximum of 32 in. Proper preparation of the grout space before grouting is very important. Bracing may be required during construction. In partially grouted walls, grout is placed only in wall spaces containing steel reinforcement. Would you like a quote? Some concrete block walls are built without rebar and without grout (grout is the concrete you pour into the cells of the concrete block after the wall is built). 1585-07, 1585-08) is a properly proportioned mixture of portland cement, graded sand, and other ingredients designed to provide a flowable grout requiring only the addition of water. Glass block is a popular choice for bathrooms, and it’s easy to see why. Steel Reinforcement for Concrete Masonry. Step 3: Find the Total Concrete Block Fill Volume Now, multiply the number of voids by the volume of the void in cubic inches to find the total grout fill volume in cubic inches. 3) contains a provision for “alternate grout placement” procedures when means and methods other than those prescribed in the document are proposed. Although not a code requirement, it is considered good practice (for all lifts except the final) to stop the level of the grout being placed approximately 1 in. Height - in. (245 and 279 mm), and. A mechanical vibrator is normally used for consolidation and reconsolidation—generally low velocity with a ¾ in. strong grout which can be easilly pumped into an existing wall. Typically called high-lift grouting within the industry, grouting with cleanouts permits the wall to be laid up to story height or to the maximum pour height shown in Table 1 prior to the installation of reinforcement and grout. Light rust, mill scale or a combination of both need not be removed from the reinforcement. When grouting between wythes, the vibrator is placed at points spaced 12 to 16 in. Open-ended units allow the units to be placed around reinforcing bars. 3). The skills involved in actually applying the cement can be practiced on scrap plywood, if desired. Shop drawings may be required before installation can begin. While the term is not found in codes or standards, it is common industry language to describe the process of constructing walls in shorter segments, without the requirements for cleanout openings, special concrete block shapes or equipment. Apply the Grout. The most common of these include increases in lift height, reduced or increased grout slumps, minimization of reconsolidation, puddling and innovative consolidation techniques. Urethane grout is pre-mixed (a big advantage for the do it yourself project), and consists of polyurethane resins and polymers that hold the silica sand together.