Brick Calculator for a Room
A 12 ft by 10 ft room, 10 ft high, with a 3×7 ft door and a 4×4 ft window, needs 3,640.72 bricks in 9-inch traditional brickwork. The order with 5 percent waste is 3,823. Cement is 11 bags of 50 kg. Sand is 74.59 CFT.
Last updated . Joint 10 mm. Mortar wastage 10 percent, then dry factor 1.33. Bags are 50 kg. No prices.
Count four walls, then subtract the door and windows. The brick starts as the traditional 9 × 4.5 × 3 in unit on two leaves. An India modular brick is on the menu. Mortar is the joint around the bricks, with a collar joint only between leaves. The size menu behind this count, including the face with no joint, is the brick sizes guide.
One wall is the brick calculator. The 9-inch and 4.5-inch CFT schedule is the Pakistan brick calculator. The pour in the floor is the concrete calculator.
Room brickwork
Cement 1440 kg/m³. Sand 1600 kg/m³. Bags are 50 kg. Openings are subtracted from the four-wall area. No price is applied.
Results
How the room is measured
Two walls use the length and two use the width, all at the same height. 2 × (12 + 10) × 10 = 440.00 square feet. The door is 21.00 square feet and the window is 16.00 square feet. Net area is 403.00 square feet. Bricks are that area divided by the face of one brick plus the joint, times the number of leaves.
On the traditional brick the face module is 238.6 mm by 86.2 mm. Two leaves make 3,640.72 bricks. Wet mortar is the 238.6 mm wall minus those solid bricks: 1.68 m³. Dry mortar is 1.68 × 1.10 × 1.33 = 2.46 m³. At 1:6, cement is one seventh of that dry volume.
Enter the outside length and width if the order should cover the corners: each wall is counted for its full length, so the corner bricks are in two walls and the result is slightly high, a safe overestimate that is larger on a 9-inch wall than on a 4.5-inch wall.
Worked example
Leave every field as it opens: 12 ft, 10 ft, and 10 ft, one 3 ft by 7 ft door, one 4 ft by 4 ft window, the traditional brick, two leaves, a 10 mm joint, 5 percent brick waste, 10 percent mortar wastage, and 1:6. Gross area reads 440.00 ft². Openings read 37.00 ft². Net area reads 403.00 ft². Bricks read 3,640.72. The order reads 3,823. Cement reads 0.51 t. Bags read 11. Sand reads 2.11 m³ · 74.59 CFT.
Frequently asked questions
How many bricks does this room need?
Leave the room at 12 ft by 10 ft, the walls 10 ft high, one door 3 ft by 7 ft, one window 4 ft by 4 ft, and the traditional 9 × 4.5 × 3 in brick on two leaves. Bricks read 3,640.72. Five percent waste makes the order 3,823. The net wall is 403.00 square feet.
How are the four walls and the openings counted?
Gross area is 2 × (length + width) × height. That is 2 × (12 + 10) × 10 = 440.00 square feet. The door is 3 × 7 = 21.00 square feet and the window is 4 × 4 = 16.00 square feet. Net area is 440.00 − 37.00 = 403.00 square feet. Openings are taken off the total, not off one wall only.
How much cement and sand is that?
At 1:6, with 10 percent mortar wastage and the 1.33 dry factor, cement is 0.51 tonnes and 11 bags of 50 kg. Sand is 2.11 m³, 74.59 CFT. Wet mortar is 1.68 m³ and dry mortar is 2.46 m³. Cement is 1,440 kg/m³ and sand is 1,600 kg/m³.
What changes on a 4.5-inch wall?
Switch to one leaf. Thickness becomes 114.3 mm, with no joint through the wall. Bricks read 1,820.36 and the order is 1,912. Cement is 0.20 tonnes and 4 bags. Sand is 0.82 m³, 29.01 CFT. The net area stays 403.00 square feet.
Is the 9-inch wall exactly 9 inches?
On the traditional brick, two leaves plus the 10 mm collar joint are 238.6 mm, 9.39 inches. A single leaf is 114.3 mm, 4.50 inches. The India modular option is a different brick: two leaves of that brick are 190 mm, which the thickness line shows. The 9-inch name applies to the 4.5 inch traditional brick.
Is this the same mortar as the brick calculator?
Yes. Wet mortar is wall volume minus the solid bricks. One leaf has no joint through the thickness. Two leaves add one collar joint. Mortar wastage is 10 percent and the dry factor is 1.33, separate from the 5 percent brick waste. The mortar calculator’s percentage of wall volume is a different method and is not used here.
How do I add another window?
Raise the window count. Two windows of 4 ft by 4 ft subtract 32.00 square feet instead of 16.00, and the net area becomes 387.00 square feet. A door or window larger than the whole room drives the net area to zero and the count stops. One straight wall, rather than a room, belongs on the brick calculator or the Pakistan page.
Should I enter inside or outside dimensions?
Enter the outside length and width when the order should cover the corners. The gross area is the full perimeter, 2 × (length + width) × height, so each corner is part of two walls and those bricks are counted twice. The 12 ft by 10 ft room still reads 3,640.72 bricks and an order of 3,823, which is slightly high, and the extra is larger on a 9-inch wall than on a 4.5-inch wall. Inside dimensions leave the corners out, and the calculator does not subtract the overlap.