Hallway Brick Wall in Sandbank, Mineral Paint and Three Coats

Bare brick in a hallway acts like a sponge with a colour problem: it pulls water out of paint in seconds and any soluble salts in the brick get carried to the surface. Sandbank at LRV 49 in a mineral matte, applied over a dampened wall in three coats, is the combination that stays even.

Coats

3

Sheen

Matte · 2u

Substrate

Brick

Touch dry

2 hours

Recoat after

6 hours

VOC

26 g/L

Full cure

28 days

Why brick is not plasterboard

Three properties of brick change the whole method. Brick is highly absorbent, it moves with moisture, and it usually contains soluble salts. Paint applied to dry brick has its water pulled into the substrate within seconds, which means the film never forms properly and the first coat looks like a wash rather than a coat.

The salts matter more than the absorption. Soluble salts in the brick dissolve into the water in the paint, migrate to the drying surface, and crystallise there. The result is efflorescence — a white powdery bloom that pushes the paint off in patches, usually within the first heating season.

Dampening before every coat

This is the single technique that separates a brick wall that lasts from one that fails. The wall should be damp, not wet: spray it with a garden sprayer, wait until the surface sheen disappears and the brick looks matt again — usually 5-10 minutes in a warm hallway — and then paint.

Wall state	Result
Bone dry	Paint water is absorbed instantly; coat 1 is patchy and dusty
Damp, matt surface	Even absorption, full film build, good adhesion
Wet to the touch	Paint dilutes on contact and runs; wait longer

Three coats, not two

Brick needs a third coat because the first one is absorbed rather than film-forming, and the second one still has mortar joints pulling colour away. The mortar is usually the last part to even out, because lime mortar is more absorbent than the brick it sits between.

• Coat 1: thinned 10% with clean water, applied with a 100 mm masonry brush, worked into the joints. Expect it to look weak.
• Coat 2: neat, 9 in roller with a 20 mm masonry sleeve, 6 hours after coat 1 at 20 C.
• Coat 3: neat, same roller, cutting in first with the brush. This is the coat that gives the wall its final colour.

Sandbank (#C9B79A, LRV 49) is a mid-depth warm neutral that flatters the texture of brick instead of fighting it. Pale colours on brick show every mortar joint as a lighter stripe and every darker brick as a blotch; an LRV 49 tone absorbs those variations and lets the texture read as texture. Trim and the surrounding plaster walls in Chalk Wash at LRV 85 give a 36-point split.

Repointing, and the cement mistake

If the mortar is crumbling, repoint before painting with a lime-based mortar matched in strength to the brick. Cement mortar is harder than most old brick: it does not flex, so moisture is forced through the brick face instead, and the brick spalls. This is the single most expensive mistake in old brickwork, and painting over crumbling mortar hides the symptom for a year or two at most.

Cure is 28 days for a mineral matte on masonry. During that time avoid hanging anything that presses flat against the wall, and do not wash it — mineral paints continue to carbonate, and moisture during the first month weakens the surface.

What matters here

• Damp the brick before every coat, then paint when the surface has gone matt again.
• Plan three coats: the first is absorbed, the second evens out the mortar joints.
• Repoint with lime mortar, never cement, before painting old brick.
• LRV 45-55 flatters brick texture; pale colours expose every joint.

Elsewhere on this wall

• Hallway in Sage Grey, Two Coats Over Plasterboard
• Sandbank in the palette
• Warm neutrals