Types of Walling Bricks

Today, we have multiple types of walling bricks to achieve the best results in our walling projects. World of Stones USA lets you dive deep in the world of walling bricks. Let’s have something thorough and useful info regarding bricks in walling.

In our earlier discussions about cobblestone pavers & block paving, we learned something about stone bricks used for paving purposes. Today, our prime focus is walling bricks. Fundamentally, it is a vast subject in itself, but we may try to concise it at our best efforts.

Similarly, we learned about different kinds of walling, such as retaining walls, garden walls, drywalling, and various wall design ideas in our previous blogs.

What Is Walling Brick?

Walling brick is a term referring to a rectangular building unit composed of similar materials and used to build walls. We know walls may be load-bearing or not. So, it influences the selection of brick types too.

Purposes & Benefits of Walling Bricks:

We know that walls can serve different purposes. Briefly,

Structural/load-bearing like core building walls, retaining walls, piers, columns, and stairs/steps. Bricks have hardness, durability, & (high bending moment) load-bearing capacities next to natural stones.
Non-load bearing, such as partition, facing or siding, fencing
Insulating.
- Weatherproof: Bricks offer protection against wind, water, heat, and frost/snow.
- Soundproof, as bricks have sound attenuation properties. For 4.5” brick thickness, it is 45 Db (decibel) & 9” thickness, and it is 50 Db.
- Wear & Tear Resistance: Bricks have wear & tear resistance next to natural stones.
Safety & security aspects like fireproof and disaster-proof. And can withstand earthquakes, storms, & other natural & human-made calamities.
Aesthetics appeal, including texture, colors, tones, and patterns.
Composite walls like brick veneers on RCC structure.

When we are going to categorize anything, we need base parameters for the same. So, we can categories walling bricks based on the following main parameters.

Types of Walling Bricks based on Functions

Structural & Non-structural Bricks:

Structural or load-bearing walls need bricks with required strength to stay with estimated live & dead loads, horizontally as well as vertically. Application areas are:

Masonry walls
Foundations
Columns & Piers

Non-structural bricks usually server other purposes than load-bearing, such as:

Facing
Veneers
Siding
Partition
Insulation

Types of Walling Bricks based on Materials Used in Manufacturing

Natural Stone Walling Bricks:

Natural stones are the most ancient material used in brick making in human civilization.
With the advent of technologies, we can cut stones in required shapes, sizes, and surface smoothness.
We can automate the process for speed & cost efficiency.
Locally available stone types can prove the ideal materials for stone bricks.
However, limestone and sandstone bricks are standard everywhere.
Natural stone bricks come with natural beauty, patterns, and styles.
So, it can improve the overall aesthetics of stone walls and offer amazing properties of natural stones.
Moreover, give many unique advantages, including durability, extended lifespan, weatherproof, versatility, eco-friendliness, and complete load-bearing capabilities.

Clay Walling Bricks:

According to Wikipedia’s article on bricks, humans began the use of clay or mud in the production of symmetrical bricks before 7,000 BC.

Sundried Clay Bricks – Required material molded in the shapes and left open under the heat of Sun for an extended period to get the required strength. In America, it was the Adobe making process that eventually leads to Sundried Brick manufacturing for mass production in a later stage.
Fired Clay Bricks – Neolithic China around 4,400 BC has used locally available fuels, wood & mineral coal to achieve 600 °C Kiln temperature that causes the clay to shimmer with the color of molten gold or silver. Kiln-master quenches the kiln with water to produce the surface glaze.

Shaping Methods for Fired Bricks:

Molded Bricks:

Raw clay mix with 25-30% sand to reduce shrinkage.
Water added in the mixture and grounded to obtain desired consistency.
Now clay presses into steel molds with a (hydraulic) pressure to give it a shape.
Finally, molded units burn at 900-1000 °C temperature to achieve the desired strength.

Dry-pressed Bricks:

It is almost similar to the soft-mud molded method.
However, it begins with a much thicker mass of clay mixture to get sharp-edged bricks.
It requires greater force to press and a longer heating period.
These all add costs in the manufacturing process but yield an accurate dimension in the products.

Extruded Bricks:

In the extrusion method, clay mixture forced through a die to shape a long cable of material in expected width and depth—the desired length achieved through cutting the cord of mixing using a wall of wires.
Stiff extrusion needs 10-15% water in a clay mixture
Soft extrusion demands 20-30% of the water in clay mixture.

Chemically Set Wall Bricks with Autoclave Method:

Sand-lime Bricks

It is also called as “Sand-Lime bricks or Calcium-Silicate bricks” because it has lime (Calcium) binding with sand (Silica) as the chief ingredients in [Lime to Sand = 1:10] proportion.
Apart from sand, it may have quartz, crushed siliceous rocks, or flint with colored minerals as other constituents.
The mixture left for complete hydration of lime.
Then, it pressed into molds.
It cured in an autoclave for three to four hours to accomplish chemical hardening.

Fly-ash Bricks

It is also called as “FaL-G bricks” because it has fly-ash, lime, & gypsum as primary materials.
It has to meet the criteria outlined in ASTM C73 – 10 Standard Specification.
Fly-ash is a byproduct of the natural coal-burning process in coal-based electric power-producing units to eliminate environmental hazards due to the dispersion of mineral coal ash.
Due to the presence of ash minerals, it remains lighter in weight and with grey to whitish shades.

Advantages:

In the absence of intense heating, its color remains grey.
You can get a smoother surface finish than other brick types. So, you can avoid plastering on it.
Its shape found completely uniform with straight and precise edges. It makes construction easy and consumes less mortar.
You can add minerals & pigments to obtain the required colors, texture, and appearance. It lets you use such bricks in ornamental or decorative purposes.

Concrete Masonry Wall Bricks:

A mixture of cement, sand, and concrete or stone aggregates/crushes in a set proportion used with water to form concrete masonry wall bricks.
Finished brick blocks/units cure using low-pressure steam.
The entire process is almost similar to create a pre-cast cement structure.
Standards BS 6073, EN 771-3, or ASTM C55 need to follow in concrete brick manufacturing.
Modern trends are favoring concrete masonry bricks a lot due to various advantages, including versatility and customization.
You can add required pigments, minerals, and chemical additives to make it as specialty bricks to serve the custom requirements.
It is eco-friendly material and processes against fired clay bricks.
Automation also establishes it as a cost-effective process.

Types of Walling Bricks on the Basis of Typical Use

Engineering Wall Bricks:

There are two types of bricks based on their typical use: Common Bricks & Engineering Bricks. We know much about standard bricks. Now, let’s learn about engineering bricks at a glance.

According to Wikipedia on Engineering Bricks, a kind of hard & dense fired bricks with some specific properties to meet particular requirements are called engineering bricks.

For instance, specific applications demand particular strength, porosity to gain water resistance, and chemical compositions to be acid-resistant.

According to § 6.4.51 of British Standard BS ISO 6707-1;2014, we can classify engineering bricks into the following classes.

Class-A Bricks

Those are sturdy and less porous bricks.
Engineering class-A bricks are blue in color due to relatively high kiln temperatures than standard fired bricks.
Those have a strength of 125 N/mm2 (18,100 lbf/sq. in).
And water absorption of less than 4.5%.

Class-B Bricks

Engineering class-B bricks are Red in color due to relatively low kiln temperature than class-A bricks.
Those have a strength of 75 N/mm2 (10,900 lbf/sq. in).
And water absorption of less than 7.0%.
Those have a semi-vitreous body.

Types of Walling Bricks on the Basis of Physical & Mechanical Properties

First Class Bricks:

These are top quality bricks with deep red, copper, or cherry colors.
They burnt thoroughly.
Neat & smooth surfaces & uniform texture.
Sharp edges, dense mass, and precise shape/size.
Scratch-resistant, anti-skid, and no water-soluble.
Metallic ringing sound when they struck against each other.
Hard to break, crack, and fracture.
No lumps of lime or salts on drying.
Water absorption – 12-15%.
The Crushing Strength – 10 N/mm2 or 105 Kg/sq. Cm.

Second Class Bricks:

Somewhat faint in colors and texture.
Small cracks and bump/pits apparent due to rough finishing.
Inferior in scratch resistance, breaks, and fractures.
May have rough edges.
Water absorption is about 16-20%
Crushing strength – 7.0 N/mm2 or 70 Kg/sq. cm.

Third Class Bricks:

Those are dull in colors and texture.
Produce dull sound when struck against each other
They are under burnt, so have rough finishing.
Inferior in scratch resistance, breaks, and fractures.
Water absorption is about 25%
Crushing strength below – 35 Kg/sq. Cm.

Fourth Class Bricks:

Overburnt.
It is severely distorted in shape & size.
Brittle in nature.
The ballast of these bricks used for filling ground, foundation, and preparation of road/path base.

Types of Walling Bricks on the Basis of Volume/Mass

Bricks are made with rectilinear dimensions or may have depressions on a side or both. It may have see-through holes in it.

Solid Bricks:

Solid bricks are made with rectilinear dimensions & have solid mass with density and weight.
No holes or frogs at all.
Solid bricks are Ideal for structural/load-bearing purposes.

Frog Bricks:

Have frogs up to 20% of the total brick mass.
Acceptable in structural & non-structural purposes.

Core Holes Bricks:

Have solid mass with holes up to 25% of the total brick mass.
Acceptable in structural & non-structural purposes.

Perforated Bricks:

Have honeybee like perforation by small but thorough holes.
Holes never exceed 25% total volume of the brick.
They were mainly used for non-structural purposes.

Cellular Bricks:

Have honeybee like holes closed at one end.
Holes never exceed 20% total volume of the brick.
They were mainly used for non-structural purposes.

Walling Brick Compositions:

Earlier, we have seen the composition of different brick types at a glance. However, the industry mostly uses fired clay bricks. So, our focus would be on listing compositions of fired bricks here given in Wikipedia.

Silica (sand) – 50% to 60% by weight
Alumina (clay) – 20% to 30% by weight
Lime – 2 to 5% by weight
Iron oxide – ≤ 7% by weight
Magnesia – less than 1% by weight

Walling Brick (Optimal) Dimensions:

Standard sizes of bricks are varying nation-to-nation. So, I have listed only the most significant countries here. Data picked from Wikipedia.

The USA has the smallest size while Australia uses the biggest one. Similarly, the UK has a smaller brick size than India.

Walling Brick Faces:

General Terms-

Beds: Top & bottom surfaces.

Headers: Ends or narrow surfaces.

Stretcher: Sides or Width giving surfaces.

The orientation of the Brick-

A brick has six sides. Based on the laying pattern of the brick corresponding to its different sides, we can give each side of a brick a unique name.

Horizontal Laying

Stretcher – A brick laid flat with its stretcher side open.

Header – A brick laid flat with its header side open.

Vertical Laying

Soldier – A brick laid vertically with a stretcher face open.

Sailor – A brick laid vertically with bed face open.

Side-Lying

Rowlock – A brick laid on the side with a stretcher face open.

Shiner – A brick laid on the side with a bed face open.

Walling Brick Laying Bonds:

Now, we know about different faces of bricks and their laying patterns during walling. If we use such faces alone or combinations of other faces, it gives us different bonds with different significance in load-bearing and, most importantly, in the appearance of the entire wall when left uncovered/open. Let’s know the most common brick bonds.

Stretcher Bond:

All rows have stretcher faced bricks. Most advisable in siding or facing walls.

Flemish Bond:

Header and stretcher face laid alternately in a row. All rows repeat the same pattern—the highly used and popular bonding pattern for structural walling.

English Bond:

Alternate rows of stretcher and header laid in a repeating sequence. It has significance in structural walling.

Monk Bond:

Two stretcher faces followed by one header face repeating in the same sequence. It rarely used but good in structural walling.

Which Brick Type Is ideal for You?

It is a crucial question, but if you have a budget and, most importantly, a foresight, I may recommend natural stone bricks for most of the projects. Natural stones have distinct advantages against the rest of the brick materials. Moreover, you can use veneers to get expected look-n-feel on your walling projects.

We offer free consulting services by our stone experts and engineers online to help you out from the selection dilemmas. Please, grab it and get the best out of your investment today.

Types of Walling Bricks – All You Need to Know