---
title: "L. Waterproofing"
url: https://formtechsys.com/protip18/
description: "Installation guide step: L. Waterproofing. Below-grade waterproofing requirements."
published: 2026-08-17
updated: 2026-08-17
---

# L. Waterproofing

Published 2026-08-17

[Formtech](https://formtechsys.com/) › [Installation guide](https://formtechsys.com/protips/) › L. Waterproofing

Below-grade waterproofing requirements.

When Formtech ICFs are used below grade, an approved, non-oil-based waterproofing system should be used. A membrane type system is preferable in most applications.