Category: Finishes
Prepared by Eng. Ahmed Fathy, Projects Manager ·
Definition
Surface preparation is cleaning a surface and removing rust, oil and old coatings before painting, by sanding, abrasive blasting or solvents, to a cleanliness grade set in the specification.
Why it matters on a project
Most industrial coating failures start with preparation, not the paint. A poorly prepared surface voids the warranty.
Measurement and pricing
Measured in square metres, stating the required grade such as Sa 2.5.
Common mistake
Painting over light rust or damp to save time, so the coating peels within months.
Frequently asked questions
What does Sa 2.5 mean?
Near-white blast cleaning that removes rust and mill scale leaving only light staining; a common grade for industrial systems.
Is hand sanding enough for steel?
For some light maintenance, yes; industrial systems usually require abrasive blasting.
Related terms
- Dry film thickness (DFT)The thickness of a coating after drying, measured in microns and checked against the specification.
- Steel structureA structural frame of steel sections connected by welding or bolts, protected from corrosion by coating.
- Emulsion paintWater-based paint for internal walls and ceilings, in various sheen levels.
- Inspection request (IR)A formal request from the contractor to the consultant to inspect work before the next stage.
Does your project need interior design and finishing drawings? Send the drawings or a short description and we reply within one working day.
Service detailsRequest a quote