Stone foundation and compatible mortar

Repair stone, joints and moisture in an older foundation without automatically applying overly rigid modern mortar or trapping moisture.

VERT / GREEN

Map friable joints, loose stones, water and deformation before cleaning/repointing.

JAUNE / YELLOW

Repair mortar must be compatible with original masonry; maximum strength is not the same as durability.

ROUGE / RED

Bulging, loose stone, deep mortar loss, major water entry or underpinning: competent mason/engineer before cosmetic repair.

Interactive triage

Superficially powdery joints
Identify mortar and degradation depth before selecting mix. Stone/wall section moves
Do not randomly rake joints; assess stability. Damp wall to insulate inside
Assess drainage and drying capacity before enclosing. Documented local maintenance
Use compatible small repairs and monitor across seasons.

Useful tools and data

Photos/moisture log
Old mortar sample
Exterior drainage plan

What the professional checks

Identify stone/mortar
Assess stability/deformation
Select compatible repointing

Official sources

Checked 2026-08-22.

CNRC — mortiers de maçonnerie ancienne

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

Whole-home action plan

Open →

Foundations and soils

Open →

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 openingsCode versions

V16

Advanced diagnostics to cross-check

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

Pyrite, pyrrhotite and ochreMasonry and lintels

V17

Specialized systems to cross-check

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

Seismic retrofitCrawl spaceUnderpinning and lifting

V18

Specialized diagnostics to verify

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

Radon mitigation

V19

Edge systems to integrate into the project

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

SIP/ICFStormwater infiltration

V27

Project risks and overlooked interfaces

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

Gutters, downspouts and roof drainage

V28

Finish and service details to verify

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

Cladding clearance above grade

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.

Tile movement joints