How this calculation works
Use the brick-plus-joint face module to estimate equivalent bricks across the net wall face. Subtract their envelope volume from the one-leaf wall volume before applying entered mortar procurement assumptions.
Wet mortar = net face area × brick width − equivalent brick count × brick envelope volumeA worked example
Nine net square metres with 190 × 90 mm brick faces and 10 mm joints contain 450 equivalent bricks. At 90 mm wall depth, the 0.81 m³ envelope contains 0.69255 m³ brick envelopes and 0.11745 m³ wet joints.
Good to know
One-leaf average geometry only. No structural mix, bond layout, water quantity, filled brick perforations, waste or strength prediction. Dry factor and density are entered assumptions.
Reference: OpenStax: rectangular volume geometry (opens in a new tab) ↗
Count joints in the face module
A repeating face occupies brick length plus one vertical joint by brick height plus one bed joint. That module is larger than the bare brick face, so dividing by bare brick area would overstate the brick envelope volume.
The reported count is an equivalent average, not an integer cutting schedule. Corners, bond offsets, wall boundaries and individual opening edges need a separate construction layout.
The two coat plaster material calculator adds estimate base and finish coat quantities separately, deduct openings per face and combine cement only at the final whole-bag purchase step.
Keep brick holes out of the joint budget
Brick envelope volume includes the external rectangular envelope, even if a brick contains perforations. The model does not assume those internal holes are filled with mortar.
Wall depth is explicitly the one-leaf brick width. A multi-leaf or cavity wall cannot be modeled merely by increasing this width without reconsidering the bond and mortar geometry.
Convert wet joints to loose procurement quantities
A dry-volume factor converts the wet joint estimate into an entered loose material total. Cement and sand are allocated by the selected volume ratio; cement bulk density then converts its share to mass.
These are procurement assumptions rather than a design mix. Round the combined cement mass to bags at the end; do not infer a verified yield, approved mortar strength or site-specific material allowance.
Use the result with the next measurement
The tile grout quantity calculator with joint depth also separates solid faces from joints, but a tile surface uses a different grid and filled-depth model from this one-leaf brick wall.
One-leaf average geometry only. No structural mix, bond layout, water quantity, filled brick perforations, waste or strength prediction. Dry factor and density are entered assumptions.
A few questions, answered
Is the equivalent brick count an order quantity?
No, it is a fractional repeating-module count.
Are brick holes filled in the model?
No, their envelope is excluded from wet mortar.
Does this specify a safe mortar mix?
No, ratios and densities are entered assumptions.