Step-by-Step Guide for Hardscape Elevations and Drainage Planning
Step 1: Set Base Elevation
Use a laser level to set the zero point at the bottom of the threshold (finished floor level of the house). Take a photo of the set point and include it in the project plans for reference. Measure elevations at key points: Just outside the threshold on the lanai. At each inside corner of the lanai where the lanai connects to the house At the outside edge of the lanai - corners and midpoint. Determine the existing slope of the lanai and ensure it meets the required slope guidelines. Step 2: Create Sufficient Slope
Maintain a slope of 1/8” to 1/10” per foot to direct water away from the house towards the deck drains. Adjustments for Proper Slope: Raise pavers along the house, if necessary, to create enough slope. Use thinner pavers (e.g., 1” pavers) to minimize elevation issues. If required, demolish and rebuild the existing lanai to achieve the correct slope. Ensure a minimum 1/2” layer of sand beneath the pavers to facilitate proper installation. Step 3: Plan Deck Drain Placement
Identify Deck Drain Locations: Place deck drains strategically between the pool coping and the house to prevent water from pooling around the pool or flowing towards the house. Typically the drain will be halfway between the edge of coping and the house. Use average distance for freeform pools Specific Placement Considerations: In narrow spaces, position the drain one paver width off the house. Extend the drain beyond the pool by the same distance it is set off the pool edge (e.g., if the drain is 3’ off the pool, extend it 3’ past the pool). Place the drain closer to the pool If you want to lower the pool and deck. This may be helpful if you’re trying to avoid the need for a guardrail or to lower the amount of retaining wall needed. Ensure the drain placement does not intersect with screen enclosure doors, dead-end into steps, or interferes with furniture. Step 4: Determine Deck Drain and Coping Height
Determine Drain Elevation: Measure distance from edge of lanai and deck drain. Use a slope of 1/8” to 1/10” per foot. So if the drain is 4’ away from the edge of the lanai, it would be somewhere between .5” and .4” lower than the edge of the lanai. Use Determine Coping Elevation: Measure distance from deck drain to outside edge of pool coping. Use a slope of 1/8” to 1/10” per foot. So if the drain is 4’ away from the edge of the coping, it would be somewhere between .5” and .4” higher than the drain. Use Use the formula: Beam Height = Coping Height - Coping Thickness - 1/2”. New option in place of deck drain: DWV Drain System - install drain pipe below pavers then cut pavers. This doesn’t change how you determine elevations. This system works better on natural stone than concrete pavers
Step 5: Add Slope to Deck and Patio
Measure the distance from the pool to the house and ensure the slope meets the guideline of 1/8” to 1/10” per foot. Adjust the the deck drain height to meet slope requirements at different areas. You need to add a slope to the drain itself If pool is closer or farther from the drain than the original spot you calculated from. Add Slope to Sides of the Patio: Measure the distance from the side of the pool to the side of patio. Slope accordingly. Add Slope along the rest of the house: Set elevations along the house to create the proper slope down to drain at the sides of the project that you set in the previous step Some inspectors will require 4” between siding and hardscape Step 6: Install Catch Basins and Drainage Pipes
Place catch basins at low points where water can not be drained off of the hardscape onto surrounding yard - such as a sunken outdoor kitchen or firepit Ensure a placement does not deviate more than 3 to 6 inches from the working drawings. Drainage Pipe Installation: Maintain a slope of 1/4” per foot for all drainage pipes. Ensure the emitter (outlet) is lower than the catch basin to allow proper water discharge. Use 45-degree bends instead of 90-degree bends to prevent clogs and ensure smooth water flow. Step 7: Plan CMU Block Wall Elevations
Calculate Rows of Blocks: Divide the total elevation difference by 8 inches to determine the number of CMU block rows needed. Example: For an elevation difference of 81.25 inches, use 11 rows of blocks. Ensure footings are at least 4 inches below grade. Mark footing elevations using grade pegs and rebar for accuracy. Step 8: Verify and Adjust On-Site
Continuous Elevation Checks: Regularly check slopes and elevations using a laser level and grade pegs. Make on-site adjustments as needed to ensure proper drainage. Record any changes and update the project plans accordingly. Best Practices
Use of Arrows on Drawings: Arrows indicating water flow can help visualize slopes, but ensure they are accurate. Place safety cones around work areas. Ensure each truck has at least two safety cones. Maintain clear communication between the design team and field crew to ensure alignment. Gather feedback after each project to improve designs and processes. Conclusion
By following these steps, you can ensure effective drainage, proper slope management, and a successful outcome for large outdoor projects. Regular checks, clear documentation, and timely adjustments are key to high-quality results.
Use this guide as a reference for complex projects involving pools, decks, sunken kitchens, and fire pits. For further clarification, consult project-specific documentation or senior team members.
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Hardscape Elevations / Drainage
