Drain Pipe Calculator Project Checklist

Introduction

Drain pipe failures are rarely mysterious — they’re checklist items that got skipped. The grade wasn’t verified, the water test didn’t happen, the cleanout got buried, the photo of the open trench was never taken. A checklist doesn’t make you a better installer; it makes you a consistent one, which is what buried infrastructure actually needs.

The Drain Pipe Calculator gives you the design targets — diameter, slope, total drop, velocity. This checklist turns those targets into a field sequence: what to confirm before digging, what to verify while the trench is open, and what to document before backfill buries the evidence. Print it; check boxes at the trench beat memory every time.

Planning Checklist (Before Digging)

• ☐ Run measured and sketched — actual pipe path with bends, not straight-line distance; high and low point elevations noted.
• ☐ Total drop verified — run length × slope ≤ available fall (outlet elevation minus inlet elevation). Recompute; this is the cheapest check on the list.
• ☐ Pipe sized to demand — capacity from the calculator covers expected flow with margin (target ≤ ~50% of full-flow capacity); velocity ≥ 2 ft/s (0.6 m/s). Method in the complete guide.
• ☐ Utility locate completed — 811 (US) or local equivalent called; marks respected with hand-dig buffer zones.
• ☐ Permit status confirmed — building department consulted; permit pulled if required. See the code compliance guide.
• ☐ Outlet planned and legal — daylight, dry well, or approved tie-in identified; stormwater not routed to sanitary sewer.
• ☐ Materials list complete — pipe (run × 1.10, rounded to sticks), gravel ((trench − pipe) × 1.10), fabric (perimeter × length × 1.15), fittings counted from the sketch + 1 spare. Takeoff method in the estimating guide.
• ☐ Spoil plan — where the excavated soil goes (spread on site or hauled); roughly 1 yd³ per 9 ft of French drain trench.
• ☐ Grade control method chosen — string line and level for short runs; rotary laser for runs over ~50 ft.

Materials Checklist (At Purchase)

• ☐ Correct pipe for the job — perforated for collection zones, solid for conveyance; SDR-35 or Schedule 40 per application (not corrugated for sanitary sewers). Specs in the material guide.
• ☐ Fittings match pipe type — same material family; long-sweep bends for direction changes; wyes (not tees) for branch tie-ins.
• ☐ Washed 3/4-in angular stone — no fines, no crusher run; bulk by the yard, not bags.
• ☐ Non-woven filter fabric — geotextile weight, not weed barrier.
• ☐ Cleanout assemblies — one per planned location, with risers and surface caps or valve boxes.
• ☐ Solvent cement, primer, cleaner — correct type for the pipe material; fresh cans (old cement thickens and fails).
• ☐ Bedding sand if the native soil is rocky or lumpy.

Trenching Checklist

• ☐ Grade stakes set — string line or laser at the design slope before excavation finishes.
• ☐ Trench bottom checked every few feet — measure down from the string/laser; no bellies, no high spots.
• ☐ Width and depth per plan — French drain typically 18 in wide × 24 in deep; sewers per depth and frost requirements.
• ☐ Utility crossings hand-exposed — no machine digging within the marked buffer.
• ☐ Bedding placed and compacted — 2–4 in (5–10 cm) of sand or fine gravel; re-check grade after bedding.
• ☐ Trench safety — spoil piled at least 2 ft from the edge; no entry into unprotected trenches at or beyond 5 ft depth.

Pipe-Laying Checklist

• ☐ Laid from the low end uphill — bells facing uphill; outlet elevation locked in first.
• ☐ Grade re-checked every 2–3 joints — drift corrected immediately, not at the end.
• ☐ Perforations oriented correctly — down for groundwater collection.
• ☐ Joints cleaned, primed, glued — quarter-turn on assembly, held 30 seconds; alignment marks matched from dry-fit.
• ☐ Fittings correct — long sweeps on turns, wyes oriented with flow, no sanitary tees on their back.
• ☐ Cleanouts placed — at direction changes, building exit, and intervals per plan; risers to finished grade.
• ☐ French drain: fabric → stone → pipe → stone → fabric folded over — the full burrito, in order.

Technique details for each step are in the pro tips guide.

Pre-Backfill Checklist (The Quality Gate)

• ☐ Water test passed — hose at the high end; prompt, steady flow at the outlet; no ponding visible at cleanouts.
• ☐ Inspection scheduled/passed — inspector sees the open trench before any backfill, if a permit requires it.
• ☐ Photographs taken — open trench with tape for depth, all fittings, cleanout locations, outlet point.
• ☐ First 12 in of cover is rock-free — clean soil or sand directly over the pipe; no stones larger than ~1 in against it.
• ☐ Backfill in 6-in lifts, compacted — no dumping full buckets onto the line.
• ☐ Cleanout risers marked and accessible — caps on, locations sketched.
• ☐ Surface restored — grade slopes away from structures; sod/seed/mulch replaced.
• ☐ Records filed — sketch with measurements, photos, material receipts, permit card.

Related Guides

• Pro Tips — the techniques behind each checklist item.
• Common Mistakes — what happens when items get skipped.
• Complete Guide — the sizing math the checklist verifies.
• Estimating Guide — quantities for the materials checklist.
• Code Compliance — inspection and permit requirements.
• FAQ — quick answers to field questions.

Get Your Number

A checklist is only as good as the numbers it verifies — run your diameter, slope, and run length through the Drain Pipe Calculator first, write the resulting targets (drop, velocity, capacity) at the top of your printed checklist, and check every trench measurement against them. The ten minutes of arithmetic up front is what makes the boxes worth checking.

Disclaimer: This checklist reflects common trade practice for planning purposes and doesn’t replace local code requirements, permit conditions, or manufacturer instructions. Verify requirements with your local building authority and consult a licensed professional for sewer connections or work governed by plumbing code. Follow excavation safety standards on every trench.