Foundation: dampproofing is not waterproofing

Choose drainage, dampproofing or waterproofing based on water exposure, cracks, groundwater, soil and assembly rather than product marketing.

VERT / GREEN

First identify water source/path, grade and drainage condition.

JAUNE / YELLOW

A dampproofing system intended for damp/intermittent exposure is not automatically waterproofing against hydrostatic water.

ROUGE / RED

Hydrostatic water, active crack, unstable foundation or failed drainage: diagnose cause and design the complete system before covering.

System triage

Basement damp only after rain
Review grade, gutters, drainage and cracks before choosing membrane. Water through slab/walls
Assess groundwater/pressure and drainage; a coating alone may be insufficient. Product sold as dampproofing
Verify evaluated use, substrate, drainage and product limitations. Drainage and membrane documented
Keep pre-backfill photos and connection details.

What the professional checks

The foundation/envelope specialist checks water source, drainage, cracks, substrate preparation and whether dampproofing or waterproofing is actually required.

Official sources

Vérifié / checked: 2026-08-23

Related path

Continue with the right tools

These links connect this page to the next useful checks and decisions without repeating the full content.

Plan a complete construction projectConnect feasibility, design, permits, concealed work, commissioning and closeout.Open →Check permit triggersPrepare the questions and documents to confirm with the local authority.Open →Check a contractorDocument licence, insurance, scope, payments, changes and warranties.Open →Update a construction costEscalate a historical cost using comparable index values.Open →Prepare pre-delivery reviewRecord documents, enclosure, systems, finishes and deficiencies before closeout.Open →

Tools related to this issue

V14

Systems to check before closing the work

V14 connects envelope, air, fire, structure, water and code instead of treating each project in isolation.

Renovation dependenciesLoad-bearing walls and openingsRoof penetrations and flashingCode versions

V16

Advanced diagnostics to cross-check

V16 connects water, soil, climate, safety, materials and seasonal use to existing projects.

Drinking-water quality and treatmentRoof snow and iceJobsite safety and silicaPyrite, pyrrhotite and ochre

V17

Specialized systems to cross-check

V17 completes gas, soil, water, fire, climate and structural interfaces.

Seismic retrofitWildfire and embersCrawl spaceUnderpinning and lifting

V18

Specialized diagnostics to verify

V18 connects systems that become costly or regulated when a primary project triggers them.

Radon mitigationLow-slope roofRoof deck over living space

V19

Edge systems to integrate into the project

V19 covers interfaces that become important when multiple home systems interact.

Skylight/tubular daylightingGreen roofSIP/ICFStormwater infiltration

V26

Often-overlooked service interfaces

V26 connects systems that cross utility, plumbing, HVAC, envelope and metering boundaries.

Electrical service, mast and meter

V27

Project risks and overlooked interfaces

V27 connects payment, water, envelope, ventilation and jobsite details that often create costly surprises.

Gutters, downspouts and roof drainageTemporary weather protection during renovationLaundry room leak containment

V28

Finish and service details to verify

V28 connects small details that become costly once finishes are closed.

Slate or clay tile roofingOutdoor faucet: freeze and backflow protectionCladding clearance above grade

V30

Shared, access and specialized interfaces

V30 connects projects where multiple systems, owners or rules meet.

Solar PV: roof attachment, structure and flashing

V32

Post-disaster and legacy systems

V32 connects contamination, storm damage, legacy materials and recommissioning before rebuilding.

Hail: roof and envelope impact assessment

V33

Invisible constraints before work

V33 checks electrical, legal, environmental and climate constraints that can block a project before demolition starts.

Permafrost and northern home foundations

V34

Use, excavation and construction constraints

V34 connects use permits, soil, excavation, neighbouring structures and public-space logistics before hard-to-reverse work.

Excavation shoring and adjacent structures

V47

V47 interfaces not to miss

These details are small on a drawing but can control water, structure or durability.

Roof-wall kickoutRoof-edge drip