Building envelope

What should I record before requesting service for condensation & fogging?

Record the exact symptom, timing, affected areas, model or component identity, recent changes, safe observations, photos, and any displayed code.

Urgency: low

What this means

Condensation & fogging covers interior moisture, between-pane fogging, frost, and humidity. Relevant observations include Condensation forms inside, Fog is trapped between panes, Ice forms on the inside, Only one room has wet windows, Window trim shows mould-like spots. The correct response depends on age, design, climate, usage, installation, recent work, and the exact manufacturer instructions; these observations narrow next steps but do not prove a failed part.

Safe checks

  • Write the symptom in plain language and when it starts, stops, or repeats.
  • Record related observations such as Condensation forms inside, Fog is trapped between panes, Ice forms on the inside, Only one room has wet windows, Window trim shows mould-like spots.
  • Collect model, age, warranty, prior invoice, photo, code, and recent-work details without opening equipment.

Stop and get help if

  • Leave or isolate the area for fire, gas, carbon monoxide, electrical exposure, collapse, sewage, or rapidly spreading water.
  • Get qualified assessment when a hidden, growing, recurring, or structural condition is suspected.

Which professional to call

Use a qualified building-envelope specialist when the condition exceeds safe user access or the visible checks do not explain it.

Find the relevant trade

Source and method

This answer combines HomeSOS's structured triage with safety boundaries supported by a public source. It does not replace inspection.

Health Canada: Home safetyReviewed August 12, 2026