CMU Rebar Shop Drawings

In masonry construction, Concrete Masonry Units (CMU) are preferred over other materials. Because it is not only a cost effective material, but it is also easy to use and strong.

The success of any masonry project is based on the accuracy and clarity of the CMU rebar shop drawings. They guide the placement of reinforcing steel within the masonry. Drawing mistakes can cause delays, code compliance issues, and other errors, costing you a fortune. The solution is partnering up with a professional CMU rebar shop drawing provider, like us, DraftingServices.com, which is highly recommended. Below is the list of essential elements that these drawings must have, as well as how we can help to make your project a great success.

Here are the actual CMU shop drawings we drafted for this project.

The Fundamentals

When discussing CMU construction, we’re normally focusing on CMU walls. With this said, the fundamental elements of any CMU rebar detailing project include the following.

1. Rebar Placement

At the heart of any CMU rebar shop drawing is the precise placement of reinforcing bars. Our expertly crafted drawings clearly indicate:

• Horizontal and Vertical Rebar Placement: The exact locations of the vertical and horizontal rebar within the CMU wall. Meeting all the structural design requirements as well as providing stability and strength.

• Wall Elevations: Elevation outlines depicting rebar layouts, to easily visualize continuity and spacing.

• CMU Details and Cross Sections: Including standard cross-sectional outlines and reinforcement details for the clarification of rebar placement at complex areas like openings, corners, and intersections.

• Bar Schedules: In detail, bar schedule lengths, listing sizes, and quantity of rebar for accurate order and installation.

• Lap Schedules: Details on how and where lap splices should be in order to adhere to compliance and maintain structural integrity.

• Call-Out Key Plan: A plan mapping out how to read notations of the shop drawings. Further including bar length to mark number, quantity, and size per location; placing remark and location required.

2. Dowel Alignment

Dowels connect CMU walls to foundations, slabs, or adjacent structural elements. Our shop include the following:

• Dowel Locations: It details the accurate measurements during installations to avoid any misalignment.

• Embedment Depth: The required embedment depths, particularly in the foundations or other structural elements. Meeting suitable anchorage depths.

• Field Adjustments: Concise notes on allowed field adjustments and tolerances to consider all on-site variations.

3. Lap Splice Details

Lap splices are necessary in instances when full-length rebar cannot be used. The term “lap” is short for overlap. The lap splice is a form of connection. The lap length is dictated by code ACI 530 unless indicated otherwise in the contract drawings. Laps develop the strength of the connection. Our drawings guarantee:

• Clearly Defined Lap Splice Lengths: It is all about adhering to the compliance and code of conduct as per the rebar grade, size, and its anticipated loads.

• Identified Locations: Clear indications of splice locations to avoid clustering or compromising strength.

• Staggering Requirements: Splices are staggered where applicable to minimize weak points in the reinforcement.

4. Lintels

Lintels, the horizontal component, support the loads above openings like doors and windows. They are important to maintain the structural stability of CMU walls as they distribute the load among openings. In our drawings, we note all lintel locations and their bearing lengths on the sides of openings.

Lintels can primarily be of three types:

• Cast-in-Place Lintels: Built on-site, concrete is poured into forms and uses rebar. Cast-in-Place Lintels are very versatile, customizable according to certain requirements.

• Precast/Prestressed Concrete Lintels: Also called Pre-Cast Lintels, are manufactured off-site and contain cast steel tendons to temporarily support during placement. Additional grout and rebar are added once installed to integrate into the surrounding masonry.

• Steel Lintels: Made with steel and must adhere to ASTM A36. Steel angle lintels, commonly used in CMU construction, should be at least 1/4 inch thick. Steel lintels are great for projects prioritizing resistance to high loads and durability.

Our firehouse shop drawings above include a variety of steel lintels at all door and window openings. There were also bond beams on this project, but they were not used as lintels to distribute loads around openings.

5. Code Compliance

It is important to mention that, in CMU construction, adherence to local, state, or national level building codes and conduct is non-negotiable.

The architect-of-record is responsible for establishing what codes should be followed. Our shop drawings comply with such codes, and those could include:

• International Building Code (IBC)

• American Concrete Institute (ACI) ACI 530/ASCE 5/TMS 402, Latest Edition “BUILDING CODE REQUIREMENTS FOR MASONRY STRUCTURES”

• Mortar conforming to the requirements of ASTM C-270

• All welded reinforcing shall be ASTM A706

• Reinforcing bars conforming to ASTM A615, GRADE 60

• Lap reinforcing in accordance with ACI 530

6. Clarity and Apperance

Apart from the technical elements, clarity also plays an important role in the success of shop drawings. Hence, we keep an eye on:

• Standardized Symbols: Adherence to all the industry recognized symbols and notations to ensure consistency and avoid misinterpretation.

• Section Views and Details: Close-ups of all the critical areas, including openings, corners and intersections to prevent vagueness.

• Legends and Notes: Clearly and concisely explain all the abbreviations, symbols, and add any special instructions.

Why Partner with DraftingServices.com for Your CMU Rebar Shop Drawings

DraftingServices.com specializes in not only accurate but also detailed and code compliant CMU rebar shop drawings that are customized for your very project. From technical content to readability, we make sure every detail is attended to. Let us handle all the hassle, and draft shop drawings for you, so that you can focus on building with peace.

Contact

Contact us today to learn more about our drafting services and how we can support your next project! We can be reached now at 718.441.3968, text us now at 646.504.5230, or email us now at brian@draftingservices.com.