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Coatings and interior systems

Paints & Decorative Coatings

A coating is the thinnest material in a building and the one most often blamed for a failure that began underneath it. Adhesion, opacity and durability depend on what the coating is applied to, how that background was prepared, and the conditions on the day, far more than on the tin itself.

These entries describe what each coating family is and what its behaviour depends on. They contain no application instructions — no coat counts, coverage figures, drying or curing times, dilution ratios or temperatures — and they state no emissions class. Those belong to the manufacturer's documentation for the specific product and to the people doing the work.

22 reference entries · educational materials reference · suitability always depends on the complete assembly and qualified professional review

Scope

What this category covers

Where the boundary of this part of the library sits, including what it deliberately leaves to qualified professionals.

  • Traditional and modern paints for internal and external surfaces
  • Protective and functional coatings applied to masonry, metal and floors
  • Penetrating and film-forming finishes for timber
  • Not covered: application methods, coverage, emissions classes, or fire and corrosion performance

Start here

Frequently referenced entries

A starting point, not a ranking — these are simply the entries most people arrive looking for.

All entries

Every paints & coatings entry

The complete set for this category, in reference order.

LimewashLimewash is slaked lime in water that carbonates into masonry and lime plaster, giving a vapour open mineral finish that weathers back rather than peeling in sheets.DistemperSoft distemper is whiting bound with animal glue size, a reversible interior paint that is not washable and can be removed with water, which is why conservation work still uses it.Clay PaintClay paint is a thin brushed or rolled interior coating of fine clays, mineral fillers and pigments, sitting between limewash and emulsion in binder chemistry and in appearance.Linseed Oil PaintLinseed oil paint uses drying oil alone as its binder, with no alkyd resin, so it penetrates timber, forms a thin film and is maintained by recoating rather than stripping.Alkyd PaintAlkyd paint cures by oxidation of a resin carried in solvent, flowing out to a harder, more level film than water borne emulsion and used mainly on joinery, trim and metal.Masonry PaintExterior masonry paint is a water borne coating formulated for alkaline, weather exposed walls, with coarser fillers and greater film build than the interior emulsion it resembles.Silicone Resin PaintA facade coating bound with silicone resin, which lines the pores of a wall so liquid water is shed while vapour still passes, without needing a mineral substrate to bond into.Elastomeric CoatingA high build, extensible facade coating applied to span fine cracking in render and masonry, at the cost of a far less vapour open film than mineral or silicone routes.Water RepellentA penetrating silane or siloxane treatment that lines the pores of masonry rather than forming a film, leaving appearance largely unchanged while the wall continues to breathe.Metal PrimerA reference on primers formulated for ferrous metal, covering barrier, sacrificial and inhibitive mechanisms, surface preparation, and why the coats are chosen as one system.Intumescent CoatingA claim-free reference on the intumescent coating category: a reactive product family that swells into an insulating char when heated, described with no performance stated.Anti Graffiti CoatingA clear surface treatment applied over masonry, render, metal or signage so that paint and marker attack can be removed without stripping the surface beneath.Bitumen PaintA thin black bitumen-based coating brushed onto metalwork, gutters, tanks and buried concrete as a barrier layer, notorious for bleeding through paints applied over it.Wood StainA colouring product that soaks into timber to change its tone without building a protective film, normally requiring a separate sealing or finishing coat over the top.Wood PreservativeA brush or spray applied timber treatment that wets the surface and cut ends of wood in place, quite distinct from timber that has had preservative driven in industrially.Exterior Wood OilA penetrating finish for exterior timber such as decking and cladding that soaks into the wood rather than forming a film, so it fades and is recoated rather than flaking.Hardwax OilAn interior timber finish combining penetrating oils with hard waxes, leaving a thin surface layer that can be repaired in patches instead of being sanded back wholesale.Clear VarnishA film-forming clear finish that builds a transparent layer over timber and takes wear as a skin, so failure means abrading back rather than simply recoating in place.Shellac and KnottingA resin-in-alcohol barrier coat used to seal knots, bleeding stains and odours that would otherwise come through a water-borne or alkyd primer and spoil the finished decoration.Line Marking PaintA coating applied as narrow lines and symbols to a set layout on floors, courts and paved areas, specified around its renewal cycle rather than whole-area appearance.Writable CoatingA coating that turns a wall or panel into a writing surface for dry markers or chalk, depending far more on substrate flatness and cure than on the colour chosen.Zinc Rich CoatingA coating loaded with metallic zinc that protects steel electrochemically rather than by barrier action alone, used on site welds, damaged galvanising and prepared steelwork.

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The same entries, clustered by what they typically do in an assembly. A material can appear in more than one cluster because it genuinely plays more than one role.

Where they appear

Parts of a building this category touches

An orientation aid only — it does not imply that any entry is suitable for that part of a particular building.

  • Foundations and groundworks · 1
  • Structural frame · 3
  • External walls · 16
  • Roofs · 2
  • Internal walls and ceilings · 13
  • Floors · 4
  • External works and landscape · 8

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Materials & Systems Encyclopedia

Reference entries for building materials, product formats and system components — what they are, what their behaviour depends on and what to ask about them.

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