Garage planning begins long before the foundation is laid, and the most critical step is the exact calculation of materials. To make an error in the number of wall blocks means either to face downtime of the brigade due to a lack of cubes, or to overpay for the delivery and storage of extra pallets, which can deteriorate under the influence of moisture. Proper calculation of blocks for the garage allows you to optimize the budget and purchase building material in one batch, which guarantees the same shade and density of products throughout the masonry.
Unlike brickwork, where the error of 5-10% is not as critical, working with large-format elements requires high accuracy, since each block has a significant weight and dimensions. Modern projects often use aerated concrete, foam concrete or ceramzytoconcrete, each of which has its own nuances when counting. In this article, we will analyze proven techniques that allow you to find out the required amount of material with an accuracy of a piece.
The choice of material and its impact on calculations
Before picking up a roulette, you need to decide on the type of block, since the size and number of pieces in a cubic meter directly depend on this. The market offers many options: from easy gas-concrete solidly ceramsite. The key difference lies in the geometry and method of laying, which makes adjustments to the final figures.
The most popular solution for garages is aerated concrete block with a size of 600×300×200 mm. This format is convenient because it allows you to quickly build walls 20 or 30 cm thick. However, if you plan to use more massive elements, such as 400×200×200 mm, the number of rows and pieces will change dramatically. It is important to bear in mind that material-density D400, D500, D600 affects the load-bearing capacity of the walls, but does not change the geometric parameters for the calculation.
And don't forget the solution. If for brick seam is 10-12 mm, then for aerated concrete on adhesive mixture it can be only 2-3 mm, which practically does not affect the volume, but significantly saves material. In the case of using cement-sand solution, the seams will be thicker, and this should be taken into account when ordering.
- 📦 Aerobic concrete: Ideal for warm garages, easy to cut, but requires accurate calculation due to the fragility of transportation.
- 🧱 Porcelain concrete: More durable and moisture resistant, often used for basement garage floors, has a standard size of 390×190×188 mm.
- 🏗️ Foamblock: Cheaper than analogues, but has worse geometry, which requires an increase in the thickness of the seam and the stock of material for trimming.
⚠️ Warning: Never mix blocks from different manufacturers in the same masonry without prior calibration. The difference in geometry even in 3-5 mm will lead to glue overuse and violation of thermal insulation.
When ordering blocks, check with the supplier the exact dimensions, as the "standard" 600 mm in practice can vary from 595 to 605 mm depending on the production technology.
Basic formula for calculating the number of blocks
There are two main ways of calculating: by wall area and by volume. Professional surveyors often use the volumetric method, since it takes into account the thickness of the walls and eliminates errors in the translation of units of measurement. First, you will need accurate data: length, width and height of the future structure.
The formula is as follows: first, the perimeter of the garage is calculated, then it is multiplied by the height of the walls, obtaining the total area. The area is then multiplied by the thickness of the block, giving the total volume of masonry in cubic meters. The resulting number is divided by the volume of one block. To avoid confusion, you can use a simplified algorithm: V total = (Length + Width) × 2 × Height × Thickness walls.
Consider an example: garage 6 by 4 meters, height 2.5 meters, block 600×300×200 mm. The perimeter will be 20 meters. Wall volume: 20 × 2.5 × 0.3 = 15 cubic meters. Knowing that one cube contains about 27.7 blocks of this size, we get: 15 × 27.7 ≈ 416 pieces. This is a “clean” volume without taking into account openings.
Why is it better to count in cubes rather than in pieces?
Suppliers often sell blocks multiples of a cubic meter or pallet. If you count only pieces, when accepting the material on the object, discrepancies may occur, since the pallet may not be exactly 100 pieces, but, for example, 96 or 104, depending on the density.
In the standard formula, the volume of the seam is usually already included in the stock ratio, which we will consider below.
Accounting for window and door openings
The most common mistake of beginners is ignoring the deduction of the area of openings. Gates, gates and windows can make up to 20-30% of the total area of walls, and buying blocks on them is a waste of money. The calculation should be made after determining all the holes in the walls.
The process looks like this: the area of each opening is calculated (width × height), then all the areas are summed up. The amount is deducted from the total area of the walls. The remaining value is multiplied by the thickness of the wall to get a "pure" volume of masonry. For the garage, the standard sizes of the gates are 2.5×2.5 m, and the wickets are 1×2.1 m.
If the project provides for installation sectional-gate or roller shutters, it is necessary to take into account the thickness of the guides and jumpers. Sometimes a concrete jumper is installed above the opening, the volume of which should also be deducted from the total number of blocks, if it is not included in the cost of a separate order.
Don't forget about the calculation. armopository. If the project involves pouring a concrete belt under the mauerlat for the roof, its volume (height × perimeter × width) is also subtracted from the total number of blocks. This is especially true for garages made of aerated concrete, where the armopod belt is mandatory.
Stock ratio and delivery combat
No calculation is complete without taking into account the inevitable losses. Blocks are fragile material, and combat during unloading, carrying and trimming is inevitable. Experienced builders always add a certain percentage of stock to the calculated amount.
The standard stock ratio is 5% for aerated concrete and foam blocks, as they are easily chipped. For a stronger one. ceramsite or cinderblock That's 3%. If you have a complex project with many angles, bay windows or non-standard opening sizes, the stock should be increased to 7-10%.
Why do you need a stock? First, a number of blocks will be taken to trim, and a full block will not be made from the half. Secondly, there is always the risk of detecting a defect in the batch or breaking the block when installing the jumpers. Buying one unit separately later is a double shipping charge, which negates all the savings.
- 🚛 Transport: When unloading the manipulator, the battle is minimal, but when hand-carrying from the pallets, it increases.
- ✂️ Undercut: The extra blocks at the end of the row are often too small and go into retreat.
- 💧 Humidity: Aerated concrete when wet can become heavier and brittle, increasing the percentage of marriage at work.
⚠️ Note: Do not store the blocks on the ground. Be sure to cover them with plastic or leave them in factory packaging to avoid saturation with moisture, which will lead to the destruction of the structure when freezing.
Calculation of fittings and jumpers
The walls of the garage are under considerable strain, especially if you plan to install heavy gates or storage on the second tier. Therefore, the calculation of blocks is inextricably linked with the calculation of reinforcement. Usually, the fittings are placed in each 3rd or 4th row of masonry.
For aerated concrete, a special fitting with a diameter of 8 mm is used, which is laid in the rods. The jumpers above the windows and gates can be purchased (gas-concrete U-blocks with rebar inside) or poured with concrete in place. If you use U-blocks, you need to count them separately, as they cost more than normal ones.
The number of fittings is calculated by the length of the walls, taking into account the overlap in the corners (usually 30-50 cm). Also do not forget about the grid for masonry of the first row, which prevents the appearance of cracks due to different shrinkage of the foundation and walls.
☑️ Pre-purchase verification
If you are building a garage with reinforced-concreteTheir volume must be subtracted from the masonry. The standard length of the jumper is equal to the width of the opening plus 50 cm on the support on each side. This is an important point that is often missed when buying extra blocks.
Summary table for the calculation of materials
For convenience, we will bring all the data into a single table. It will help structure information and not forget anything when going to a construction store or ordering a machine with material.
| Parameter | Meaning/Formula | Note |
|---|---|---|
| Perimeter of walls | (Length + Width) × 2 | Without taking into account the thickness of the corner blocks |
| Wall area (rough) | Perimeter × Height | Including openings |
| Area of openings | Sum (Big width × Height) | Gates, doors, windows. |
| Net masonry volume | (Wall area - Opening area) × Thickness | In cubic metres |
| Total number of blocks | (Net volume × 1 m3 quantity + 5%) | With the stock for the fight. |
Using this table, you can easily substitute your values and get the final figure. Don't forget that weld thickness of 2-3 mm with adhesive technology, it practically does not affect the volume, but when using cement mortar, the volume of masonry can increase by 10-15% due to seams, which requires a decrease in the number of ordered blocks.
Frequently Asked Questions (FAQ)
How many blocks are in one pallet?
The amount depends on the size of the block and the load capacity of the pallet. For standard aerated concrete 600×300×200 mm on the pallet usually placed 2.16 m3 (about 60 pieces) or 2.88 m3 (about 80 pieces). Always check with the supplier for the exact information, as the equipment may differ.
Should the thickness of the angles be taken into account when calculating the perimeter?
For accurate calculation of the masonry volume, it is better to use the inner or middle line of walls. However, for an approximate calculation of the number of blocks, it is enough to take the external dimensions along the axes, since the error will be minimal and will be overlaid by the reserve.
Can I use the blocks left over from the cut?
Yes, aerated concrete and foam block trimmings are great for filling irresponsible areas, creating jumpers over narrow openings or using as non-removable formwork. The main thing is not to use too small fragments in corners or under load.
How to calculate the amount of glue for blocks?
The consumption of glue depends on the thickness of the seam and the geometry of the block. On average, 1 bag (25 kg) of dry mixture with a seam of 2-3 mm is taken per 1 m3 of masonry. If the geometry of the blocks is poor and the seam is thicker, the flow rate can rise to 1.5 bags per cube.
Which is cheaper: build a garage of blocks or bricks?
A block garage will be cheaper and faster in construction due to the size of the elements and the speed of laying. Brick requires more time, mortar and qualification of the mason, which significantly increases the final estimate, despite the similar cost of material per cube.