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Sheet S-111
PPDPDD CE

Masonryconcept

Mortar joint profiles and weathering

One-line orientation

The shape of a tooled mortar joint controls how well a masonry wall sheds water. Concave and V joints resist rain well; properly tooled weathered joints can also perform well, while struck and raked joints are less resistant.

Key points

  • Tooled, compressed profiles shed water best:
    • Concave — curved inward with a jointer tool; sheds water; good for weathering and freeze-thaw. The standard exterior joint.
    • Vee — sharp “V”; also good for weathering and freeze-thaw; pronounced shadow line.
  • Sloped/runoff profiles (exterior-capable):
    • Weathered — properly tooled weathered joints can perform well against rain.
    • Struck is not a preferred exterior joint. Concave and V joints perform better against rain.
  • Poor or non-exterior profiles:
    • Flush — mortar even with the face. It may be used outside, but concave and V joints are the stronger high-yield answers for rain resistance.
    • Raked — mortar recessed for shadow/texture; leaves a ledge that holds water → poor for weather.
  • Pointing vs structural mortar: structural mortar carries load; pointing mortar (often Type O or N) is the visible joint material, chosen for flexibility/color. Repointing removes and replaces deteriorated joint mortar to block water and extend service life.

Mortar joint profiles, ranked by how well the face sheds water

Brick and mortar section stay constant down the sheet; only the exposed face changes, and that shape is what sets the rank.

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Scroll horizontally to explore

Six mortar joint profiles drawn as masonry cut sections and ranked in three tiers Six masonry cut sections, all drawn the same way — a thin hatched brick course above and below a deep mortar band, with the exposed mortar face as the only geometry that changes. They are grouped in three ranked tiers, each tier named in a left rail. Best: concave, curved inward by a jointer tool and the standard exterior joint, and vee, a sharp V with a pronounced shadow line; both are tooled and compressed, both carry a blue runoff arrow. Good: weathered, whose top edge is recessed and slopes outward to meet the face at the bottom, and struck, which is the inverse — full at the top and pressed in at the bottom — so although it too carries a runoff arrow, a small blue pool sits on the upward-facing shelf it leaves, showing why it sheds less effectively than weathered. Poor: flush, where the mortar is even with the face and simply not optimized to shed water, suited to interiors and flat surfaces; and raked, where the mortar is recessed to form a horizontal ledge with a blue pool standing on it, the worst profile for weather. BESTtooled + compressedConcavethe standard exterior jointVeepronounced shadow lineGOODsloped for runoffWeatheredtop slopes outwardStruckrunoff, but less than weatheredPOORnot optimized to shed waterFlushfair — interiors / flat surfacesRakedworst — ledge holds water
  • fine hatch = cut brick · dark edge = the mortar face
  • blue = water · arrow runs off, pool stays

Raked joints leave a ledge that holds water; avoid them for exposed freeze-thaw conditions.

Struck is drawn as FBC 349 shows it — weathered inverted: full at the top, pressed in at the bottom, leaving a small upward-facing shelf, which is why it sheds less effectively than weathered. The card's wording (“bottom protrudes”) describes the opposite profile; that conflict is open for the owner.

Confusions / comparison

JointProfileWeather performanceTypical use
ConcaveTooled, curved in (compressed)Best — sheds water, freeze-thawStandard exterior
VeeTooled “V” (compressed)Best — sheds water, freeze-thawExterior, decorative shadow
WeatheredSloped profileGood when properly tooledExterior-capable
StruckTop in, bottom outLess rain-resistantDo not use as the preferred exterior answer
FlushEven with faceReference- and detail-dependentInterior or exterior, as detailed
RakedRecessed, ledgeWorst — holds waterDecorative, interior

→ Mortar types (this module): M/S/N/O/K selection, pointing uses O/N · Brick types & grades (this module): weathering grades pair with joint choice · Brick construction (this module): coping + joints together shed water.

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