Our Exterior Painting Process

Exterior coatings are affected by rain, temperature, sunlight, moisture movement, and the condition of the substrate. The six stages below explain the checks and preparation that may be required before a suitable coating system can be quoted.

Step 1: External Survey & Scaffolding Assessment

The first step is an external survey for paint failure, timber rot, cracked render, damp ingress, and biological growth such as algae or lichen. Access requirements and possible lead coatings on older properties also need to be considered. If scaffold or specialist remediation is required, the quote should identify who will arrange it and how it affects the cost.

Step 2: Pressure Washing & Surface Cleaning

All exterior surfaces are pressure washed using a professional Kärcher unit to blast away years of accumulated dirt, grime, moss, and loose material. For surfaces with persistent algae or green biological growth — a common problem on north-facing elevations across Hitchin and Stevenage — we apply a specialist anti-fungal biocidal wash and allow it to dwell before rinsing. This kills spores at the root, preventing regrowth beneath the new paint film. Surfaces are then left to dry thoroughly before any coatings are applied.

Step 3: Timber Repairs & Rot Treatment

Rotten or damaged timber — whether on window sills, fascia boards, barge boards, or door frames — is carefully assessed. Minor rot is treated with a liquid wood hardener to consolidate the fibres, then rebuilt using a two-part epoxy repair system such as Timbabuild Dry Flex. This is a durable, sandable compound that bonds permanently to the surrounding timber and can be painted over within hours. Where damage is too extensive for repair, we splice in new pressure-treated softwood or hardwood sections. For comprehensive sash window restoration, see our detailed guide: How to Restore Sash Windows.

Step 4: Masonry Crack Repair & Stabilisation

Cracks in rendered walls, pebbledash, or exposed brickwork are raked out and filled with appropriate repair mortars or flexible fillers. Loose or blown render is hacked off and patched with a sand-and-cement mix matched to the existing texture. For chalky, powdery, or friable masonry — where the surface crumbles when touched — we apply Sandtex Stabilising Solution, a penetrating liquid that soaks into the substrate and binds loose particles together, creating a solid foundation for paint. This level of thorough preparation is especially important for the older period properties we decorate in St Albans and Harpenden. Without this step, topcoats simply peel away within a season or two.

Step 5: Priming

Correct priming is the bridge between preparation and a lasting finish. On bare masonry, we use Dulux Weathershield Stabilising Primer to seal the surface and improve topcoat adhesion. On areas where old paint is flaking or the substrate varies between painted and bare patches, Zinsser Peel Stop is our go-to — a flexible, elastic primer that bridges hairline cracks and creates a uniform base. All bare timber and repaired woodwork receives a dedicated exterior wood primer before topcoating. We never skip this step, even when manufacturers claim their topcoats are "self-priming."

Step 6: Topcoats — Built to Last

The topcoat must be compatible with the substrate, primer, existing coating, exposure, and desired sheen. Masonry and exterior woodwork need different systems. The written quote should identify the proposed products, number of coats, coverage assumptions, and drying conditions, with application following the current manufacturer instructions.

Exterior Services:

• ✓Render & Pebbledash Painting
• ✓Sash Window Woodwork Restoration
• ✓Front Door High-Gloss Painting
• ✓Fascias, Soffits & Bargeboards
• ✓Guttering & Downpipes Painting
• ✓Fences, Gates & Garden Decking