Engineering reference
Project verification required
Engineering disclaimer: Calculators and methods on this page are engineering references for education and preliminary design discussion. They are not a substitute for project specifications, PE-stamped calculations, or ALFA confirmation of product ratings for your service conditions. Project-specific verification required.
Purpose
Engineering principles for subsoil / groundwater collection using perforated or slotted thermoplastic pipe — patterns only when ALFA-documented.
Applications
- Subsoil drainage, perimeter drains, French drains, groundwater control
- Filter media and geotextile selection by the civil designer
- Perforation / slot orientation and flow entry concepts
- Pipe surround, installation, maintenance access
Critical rule
Hole size, hole spacing, slot dimensions, slot spacing, and perforation patterns are published only if supported by ALFA documentation. Otherwise this center provides principles only — request confirmation before BOQ lock-in.
Perforated ≠ slotted. Do not substitute without design review.
Related resources
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