Building sturdy steps from concrete masonry units, commonly known as cinder blocks, is a popular and straightforward project for improving access to outdoor spaces like decks, sheds, or patios. This method offers a highly durable and inexpensive solution that can be easily customized to fit various landscape designs. The uniform dimensions of the blocks make this a beginner-friendly construction task. Properly executed, these steps provide a long-lasting, stable structure that resists weathering.
Essential Planning and Material Calculation
The initial phase of construction requires careful planning to ensure the steps are comfortable and meet safety standards. Determining the total rise—the vertical distance from the ground to the landing surface—is the first measurement needed for the design. A comfortable step typically adheres to the rule that the rise plus the run (the depth of the tread) should equal approximately 17 to 18 inches. Dividing the total rise by a comfortable individual step height (usually between 6 and 8 inches) determines the number of courses needed.
Once dimensions are established, calculating materials is straightforward using the standard block size of 8x8x16 inches. The number of blocks required for each course is multiplied by the total number of courses to determine the overall block count. Necessary materials include the concrete blocks, decorative capstones or pavers for the treads, crushed gravel or paver base for the foundation, and leveling sand. Construction-grade landscape adhesive or masonry mortar will be needed to secure the structure, along with basic tools like a level, shovel, and tamper.
Preparing the Site and Laying the Base
A stable foundation is necessary for the longevity of the steps, preventing shifting or settling over time. Excavate the area where the steps will sit, ensuring the space is slightly wider and deeper than the planned structure. This excavation must accommodate the base material and the first course of blocks, allowing the finished steps to meet the ground level seamlessly.
After excavation, add a layer of crushed gravel (paver base) to the trench and thoroughly compact it using a hand tamper or plate compactor. This gravel layer provides excellent drainage and distributes the load evenly, which is particularly important for mitigating the effects of frost heave in colder climates. Spread a thin layer of leveling sand over the compacted gravel to create a smooth surface for the first course of blocks. Ensure the base is level from side to side and has a slight slope (about one-eighth inch per foot) away from the main structure to encourage water runoff.
Stacking the Blocks and Securing the Structure
The first course of blocks must be laid directly onto the prepared base, ensuring they are perfectly level and square to the structure they are accessing. This initial row dictates the alignment and stability of the entire project, so precise placement is necessary before proceeding. Subsequent courses are built upon the first using a running bond pattern, where the vertical joints of one course are centered over the blocks below. This staggered arrangement maximizes the structural integrity and lateral strength of the wall.
Before placing the next course, apply a generous bead of construction-grade landscape adhesive to the top surface of the blocks below. Traditional masonry mortar can be used for a more permanent installation, which requires a longer curing time but creates a monolithic structure. As the structure rises, fill the hollow cores of the blocks with crushed gravel or concrete for added mass and stability. This filling process is important for blocks supporting the capstones, ensuring a solid surface, and continues until the desired height is reached.
Adding Capstones and Final Touches
The final step involves installing the capstones, which serve as the finished treads and provide a professional, comfortable walking surface. Capstones are typically wider and deeper than the underlying blocks, often featuring a slight overhang (nosing) that improves footing and aesthetics. Secure these treads to the top course of blocks using the same construction adhesive or mortar used previously. The slight overhang should be consistent across all steps, usually extending about one to one-and-a-half inches past the face of the block.
For aesthetic purposes, the visible sides of the structure can be finished with materials like a concrete skim coat, veneer stone, or durable masonry paint to match the surrounding environment. After all capstones are secured and finishes are applied, the steps must be allowed to cure completely before heavy use. Adhesives and mortars require specific curing times, often ranging from 24 to 72 hours, ensuring the chemical bond reaches maximum strength.