Check closing fit and visible seals
With the door closed, note where cold air is noticeable and whether there is a visible gap. Torn weatherstripping and incomplete closing deserve separate checks. Do not cover sill drainage holes in an attempt to stop air movement.
Distinguish a draft from cold glass
Feeling cold near glazing does not always mean air is entering through a gap. Note actual air movement, visible seal damage and condensation separately. A professional assessment can distinguish panel fit, seals, glazing and frame conditions.
Describe moisture accurately
Surface condensation can relate to indoor humidity and cold surfaces. Fog between panes may point to the insulated glass unit. Photograph where moisture appears and when it occurs; new weatherstripping does not address every moisture problem.
The guidance here is general. Your door manufacturer’s instructions and an assessment of the actual system take precedence.
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