Identify the previous coating where possible and show peeling, glossy or stained areas. Different finishes affect the preparation method. Unknown or suspect hazardous coatings are excluded; a sanding enquiry does not authorise stripping every old surface regardless of its composition.
The final preparation should suit the selected oil or compatible coating. Decide that finish before the sanding scope is confirmed. Sanding, oiling and deck painting are separate tasks; list the required stages so exposed prepared timber has an agreed follow-on plan.
Sanding removes timber as well as surface material. Heavily worn, thin or damaged boards may not be suitable. The task concerns sound boards, and surface preparation must not be used to conceal rot or substitute for a separate deck repair assessment.
Prepare and sand accepted sound boards with appropriate abrasive stages and dust control, within the agreed accessible area. Scope limits: Sound ordinary accessible boards only. No structural restoration, rot concealment, hazardous coating removal, asbestos or specialist dust remediation.