Sealtek Cape Publishes Technical Guide on Below-Grade Waterproofing Specification for Civil Infrastructure

New article sets out what civil contractors need to evaluate when specifying waterproofing systems for retention structures, cisterns, and pump stations in the Western Cape.

Somerset West, Western Cape — Sealtek Cape has published a technical article addressing the specific waterproofing challenges that below-grade civil infrastructure presents, and why systems specified for above-grade or residential applications routinely fall short when applied to public sector structures operating under continuous groundwater contact.

The piece is written for civil engineering contractors, project managers, and quantity surveyors working on municipal and government-adjacent infrastructure across Cape Town, the West Coast, the Overberg, the Garden Route, and the Helderberg.

Retention structures, underground cisterns, and pump stations share conditions that most waterproofing products were never designed to handle.

These structures don't experience occasional exposure to water.

They sit in sustained contact with groundwater, often at or below the water table by function, with no dry periods between events to allow for inspection or early intervention.

A system that performs adequately on a roof deck or residential basement will not necessarily hold against continuous negative-side hydrostatic pressure on a civil structure once it is backfilled and operational.

What The Article Explores

The article examines what hydrostatic load means in practice for below-grade civil geometries, why chemical resistance is a baseline specification requirement rather than a premium consideration for structures handling stormwater run-off or wastewater, and how local content requirements and procurement documentation factor into product selection on public sector tenders.

It also sets out the questions a contractor should be asking of any proposed system before a brand or supplier conversation begins.

A Key Insight

One point the piece raises with particular clarity: once a retention wall, cistern, or pump station is backfilled, the waterproofing layer is effectively inaccessible without excavation.

That single fact changes the risk calculation entirely, and makes correct specification and application technique at installation the only opportunity to get it right.

To read the full article, visit Below-Grade Waterproofing for Civil Infrastructure: What Contractors Need to Know on the Sealtek Cape website.

About Sealtek Cape

Sealtek Cape is a waterproofing solutions provider based in Somerset West, supplying locally manufactured Sealtek products for domestic, commercial, and civil projects across the Western Cape.

The company combines on-site assessments, technical support, and an accredited applicator network to deliver long-lasting, environmentally responsible waterproofing systems formulated for South African conditions.

Contact

Sealtek Cape

4 Victoria St, Van Ryneveld, Cape Town, 7139, South Africa