Decision tool / observation to evidence
A symptom does not choose the repair method.
A crack, wet joint, sagging floor, or settled slab can sit at the end of several different cause chains. Route the evidence first.
Observation router
Choose what you can see.
The output identifies evidence and professional questions. It does not diagnose the cause or select a repair.
Wall bowing or a horizontal wall crack
- Evidence to collect
- Measure wall position and displacement; map the crack; record drainage, grade, soil contact, and changes over time.
- Repair paths that may enter the discussion
- Engineered wall bracing or anchors, rebuilding, drainage work, or another designed stabilization path may be discussed after the wall and loads are evaluated.
- Professional handoff
- A qualified structural professional should establish safety, cause, and design responsibility before a system is selected.
Stair-step or diagonal masonry cracking
- Evidence to collect
- Record crack path, width, offset, displaced units, nearby openings, additions, elevation changes, and whether the pattern is moving.
- Repair paths that may enter the discussion
- Compatible masonry repair, monitoring, settlement stabilization, wall repair, or water management may enter the scope after the movement question is resolved.
- Professional handoff
- Escalate when the crack is active, displaced, repeated across the building, or tied to a structural alteration.
Vertical foundation-wall crack
- Evidence to collect
- Map width, depth, offset, moisture, wall type, age of the crack, and change across seasons. A single photo does not establish the cause.
- Repair paths that may enter the discussion
- Monitoring, compatible crack repair, injection, exterior water work, or structural repair can describe very different scopes.
- Professional handoff
- Use a structural review when there is displacement, active change, wall movement, or uncertainty about the load-bearing condition.
Sagging or uneven floors
- Evidence to collect
- Inspect joists, beams, posts, connections, bearing points, footings, moisture damage, span, and measured elevations.
- Repair paths that may enter the discussion
- Member repair, sistering, beam or column work, new footings, shimming, or foundation stabilization may be considered only after the weak link is located.
- Professional handoff
- A design professional belongs in the decision when supports or load paths will change, damage is active, or the cause is disputed.
Sinking or uneven concrete slab
- Evidence to collect
- Map settlement, cracking, joint condition, slab thickness if known, base loss, voids, drainage, utilities, and the desired final elevation.
- Repair paths that may enter the discussion
- Leveling, void filling, partial replacement, full replacement, drainage correction, or no immediate work may be discussed from the observed conditions.
- Professional handoff
- Structural review is warranted when the slab supports structural loads, movement affects the building, or lifting could alter connected systems.
Water at a wall, crack, or wall-floor joint
- Evidence to collect
- Record rainfall or thaw timing, grade, roof discharge, plumbing, groundwater clues, stains, salts, and where water first appears.
- Repair paths that may enter the discussion
- Surface drainage, subsurface drainage, plumbing repair, joint or crack work, and structural repair answer different problems and should not be bundled by default.
- Professional handoff
- Bring in structural expertise when water accompanies movement, displacement, material loss, or a proposed change to the foundation.
Stone or brick mortar loss
- Evidence to collect
- Document units, mortar, loose or displaced areas, prior hard patches, coatings, drainage, and changes between original and later work.
- Repair paths that may enter the discussion
- Compatible repointing, selective rebuilding, drainage correction, temporary support, or designed stabilization may be considered in sequence.
- Professional handoff
- Use preservation and structural expertise when units move, support is uncertain, or repair will replace load-bearing masonry.
Doors or windows sticking
- Evidence to collect
- Record season, humidity, frame condition, floor elevations, nearby cracks, additions, and whether several openings changed together.
- Repair paths that may enter the discussion
- Carpentry adjustment, moisture correction, monitoring, member repair, or foundation work are all possible conversations. The symptom alone does not choose one.
- Professional handoff
- Escalate when the opening change is sudden, progressive, paired with displacement, or part of a wider movement pattern.
Why the matrix stops short
The same symptom can belong to different systems.
HUD inspection guidance lists shrinkage, temperature, restraint, soil movement, groundwater, and applied loads among the factors that can produce foundation-wall and floor cracks. The visible line does not tell you which factor controls the repair.
The matrix therefore names evidence and possible conversations. It never turns a crack pattern into a product recommendation.
How to use it
Carry the evidence into the next appointment.
Bring dated photos, measurements, drainage history, prior plans, repair records, and the exact locations that changed. Ask the contractor or engineer to explain which observations support the scope.
If the explanation depends on soil, water, or hidden framing that nobody examined, that dependency belongs in the written limitations.
Safety boundary
Visible instability overrides the worksheet.
Leave an area that appears at risk of collapse or involves falling material, damaged utilities, or an unsafe floor. Contact emergency services or the local building authority before seeking repair pricing.
Technical sources / checked September 10, 2026