Help with paint Painting outdoors

Painting outdoor woodwork

Exterior timber is painted dry (under 15% moisture), in dry weather between 10 and 25 °C, after stripping what is flaking, sanding, filling and priming the bare wood: tinted undercoat, then two coats of Multi-Surface Eggshell, Satin or Gloss — three on south- and west-facing elevations. Done well, this work protects the wood for up to ten years, provided it gets light maintenance roughly every three years: a wash, touch-ups where it wears, one coat on the exposed face. This guide covers windows, shutters, gates, eaves and cladding.

Page updated September 2026 · by the Mylands France colour team

Glazing-barred window and hinged shutters painted in a deep satin blue-grey on a cool white rendered façade, stone sill, geraniums — Bond Street No.219 in Multi-Surface Satin: windows and shutters, three coats on the west side

Understanding

What paint does for exterior timber, and what it does not

Outdoors, paint is first a protection: it keeps water out of the wood and filters the UV that greys it. It protects sound wood; it does not repair rotten wood, which it hides for six months before blistering. Hence the first rule: probe before painting. The second: the wood must be dry — under 15% moisture, which timber reaches after two or three days of dry weather; painted damp, it throws the paint off in blisters at the first warm spell.

All the Mylands Multi-Surface finishes — Eggshell, Satin, Gloss — are formulated for interior and exterior use, over primer and undercoat. Their exterior data sheet is precise: apply at 8–10 °C at least, air and substrate, and 3 °C above the dew point; two coats, three on south- and west-facing elevations; not on decking or on a horizontal surface where water stands. Properly applied, they protect for up to ten years with a maintenance coat roughly every three years.

The method

Painting exterior timber in nine steps

01

Probe and decide

The tip of a screwdriver on the lower corners, the joints, the window sills: wood that gives is rotten. Small area: dig it out, treat with hardener, fill. Large area: replace the piece. Wood green with algae is treated with a fungicidal wash and rinsed.
02

Wash

Sugar soap with a sponge or a scrubbing brush, rinse with clean water, never a pressure washer on painted wood (it drives the water in). Two days' drying in dry weather.
03

Strip what is coming away

Triangular scraper on everything blistering or flaking, back to sound wood or to paint that holds; a heat gun for thick layers, without scorching the wood. Old paint that holds is kept and sanded.
04

Sand

80 grit on bared wood to smooth it, 120 everywhere to key the old paint and feather the edges of stripped areas, 180 on the mouldings. Dust off with a damp cloth.
05

Fill and seal

Exterior wood filler in cracks and holes; flexible sealant in the joints between wood and masonry, where water gets in. Sanded at 180 once dry.
06

Prime the bare wood

Multi-Surface Primer on every area of bare wood, two coats on the end grain (ends of boards, bottoms of stiles) and the knots. A night's drying. Over sound, sanded old paint, primer is not needed.
07

Tinted undercoat

One coat of tinted Primer & Undercoat over the whole: it unifies the stripped and the old areas, without which the finish shows the difference for months. 3 to 4 h drying, a light rub-down.
08

Two coats of finish, three facing south

By brush, along the grain, in thin coats: glazing bars and mouldings first, rails, then stiles. Recoatable in 3 to 4 h in dry weather; the next day is safer. On south- and west-facing elevations, a third coat.
09

The edge of the glass, and the upkeep

On a window, the paint laps 1 to 2 mm onto the glass: that is the seal that stops water getting under the putty. Then, every three years: a wash, touch-ups where worn, one coat on the most exposed face.

Close-up of a window stile under preparation: half stripped back to pale wood, the other half still in old flaking paint, triangular scraper and abrasive paper on the sill — Strip what is coming away, keep what holds, feather the edges by sanding

By element

Windows, shutters, gates, eaves, cladding: what changes

Element	Weak points	Recommended finish	Worth knowing
Windows	Bottom rail, sill, joint with the glass	Satin or Gloss	Lap 1 to 2 mm onto the glass; paint windows open, leave them ajar for a night
Hinged shutters	Bottoms of boards, end grain, hinges	Eggshell or Satin	Take them off and paint flat on trestles, all faces and edges; hinges in the same finish
Gate, wicket	Bottoms of posts, joints	Satin or Gloss	Take off the hinges if possible; buried parts or those touching the ground are beyond the reach of paint
Eaves, fascia boards	End grain, junction with the gutter	Eggshell or Satin	Scaffold or a stable ladder; do it at the same time as the gutter
Cladding, exterior boarding	Bottoms of boards, end grain, green north faces	Eggshell	Fungicidal wash on green areas; paint board by board along the length
Beams, half-timbering	Cracks, shrinkage	Eggshell	Do not fill shrinkage cracks with hard filler; structural timber breathes

A timber deck, a floor, a flat handrail: paint will not hold there, water stands. Oil or a saturating stain instead. Shutters and their colours: Colours for shutters.

The colours

Six exterior joinery colours, by façade

Outdoors, a colour looks lighter and cooler than indoors: these six shades are chosen one step deeper. The method in detail: Using exterior paint colours.

Deep blue-grey

The blue of townhouse joinery on a cool white render: crisp, elegant, it ages without showing it.

Joinery · Bond Street No.219 Façade · St Clement No.11

Village grey-green

On golden stone or a warm render, the grey-green of shutters that seem to have always been there.

Shutters · Long Acre No.102 Façade · Lots Road No.24

Warm white

The white windows of a brick house or a coloured façade: a warm off-white, never a pure white, which would turn blue.

Windows · Holland Park No.5 Façade · Cadogan Stone No.59

Deep green

The bottle green of country shutters and garden gates, with tile and Virginia creeper.

Shutters & gate · Sorrel Green No.207 Façade · Walbrook No.142

Brown-grey

The brown-grey of cladding or eaves that step back behind the garden; with a lighter door.

Cladding · Westmoreland No.160 Door · St Martins No.37

Grey-black

The very deep grey of modern windows: it draws the façade in line, on a pale render or brick.

Windows · Downing Street No.10 Façade · Charterhouse No.4

To avoid

What makes an exterior paint blister

Painting damp wood. After rain, two dry days; wood above 15% throws the paint off.
Painting in full sun or in the evening. Sun dries the surface before the body; dew marks a fresh coat. Mornings, in the shade.
Painting over flaking paint. It takes the new coat with it; strip what is coming away.
Forgetting the end grain. The bottoms of boards and stiles drink water through the fibres; two coats of primer there.
The pressure washer. It drives water into the wood and under the paint; sponge and scrubbing brush.
A dark colour facing south in two coats. It heats up and wears faster; three coats, and a mid shade if possible.

Hinged shutters taken off and laid flat on trestles in a garden, a hand painting the boards bottle green with a flat brush, tin of paint, soft light — Sorrel Green No.207: shutters flat on trestles, every face, every edge

Frequently asked questions

Your questions, our answers

Which season for painting outdoors?

Spring to autumn, outside heatwaves: between 10 and 25 °C, air and substrate, with no rain forecast for 48 h, and 3 °C above the dew point — which means not on misty mornings or cool evenings. May–June and September are the best months.

Eggshell, Satin or Gloss outdoors?

All three hold. Eggshell for a soft, discreet look (shutters, cladding), Satin for what gets handled (windows, gates), Gloss for the front door and classic joinery. The glossier the finish, the more careful the preparation has to be.

How long does it last?

Up to ten years on sound, well-prepared wood, with maintenance roughly every three years: a wash, touch-ups where worn, one coat on the most exposed face. A south face with no maintenance starts to chalk around the fourth year.

Can stained or oiled wood be painted?

Stained wood, yes, after careful sanding and Multi-Surface Primer throughout. Oiled or saturated wood, no: the oil stops adhesion; it has to weather grey for a season, or be degreased and sanded deeply.

What about an aluminium or uPVC window?

Degrease, very fine sanding, Multi-Surface Primer after an adhesion test on a hidden area, then two coats of Satin. On uPVC, light or mid shades only — a dark colour heats up and distorts the profiles.