Types of bond
When laying bricks, the manner in which the bricks overlap is called the bond. A brick laid with the longest side exposed is called a stretcher brick, as opposed to a header, where only the smallest end of the brick is exposed to the weather. The length of one stretcher is the same as two header bricks, side-by-side, including the 10mm joint between.
The thickness of a brick wall is measured using a unit of length known as 'the brick'. This standard can be used consistently with the wide variety of brick sizes available ("modular", "Norman" brick, etc.). The length of the longest face for a particular size of brick equals "one brick", for the purposes of measuring a wall built from such bricks.
Stretcher bond
Stretcher bond (also known as running bond) is the most common bond in modern times, as it is easy to lay, with little waste. It is entirely composed of stretcher bricks, set in rows (or "courses") that are offset by half a brick.
Running bond uses no header bricks, allowing for a thin wall of one layer (half of a 'brick' unit). Two such walls may be built close together with a gap between. The two "skins" are usually tied together at regular intervals using wall ties. For this reason this bond is sometimes known as "cavity wallbond", although it is possible to give the appearance of other bonds in a half-brick cavity wall, either through extensive brick-cutting or the use of purpose-made half-bricks. In some climates the cavity may be filled with cavity wall insulation.
Stretcher bond may also be used to build a single-wythe(one-brick thick) wall without a deliberate cavity. In this case, wall ties are used to hold the two wythes together. The main advantage of this technique is that it allows walls with both faces visible, such as domestic dwarf walls (low-height walls where the part of the structure above is built of a lighter, framed material such as glass) to be built using low-cost bricks that have only two fair faces, called "face bricks". Laying any such brick as a header would reveal a poorly finished header face on one side of the wall. These walls are also used in situations where stronger load-bearing capacity is required than that given by a single stretcher bond wall with engaged piers.
English bond
This bond is made up of alternating courses of stretchers and headers. This produces a solid wall that is a full brick in depth. English bond is fairly easy to lay and is the strongest bond for a one-brick-thick wall. If only one face of an English bond wall is exposed, one quarter of the bricks are not visible, and hence may be of low visual quality.
Quarter bond
Quarter bond is formed by a part (or bat) brick known as a 'queen closer'. This is a brick cut in half lengthways, generally along the frog and laid in the course next to the corner brick or 'quoin header'. Whereas the stretcher or half bond is formed by successive courses being staggered by half a brick, the Flemish and English bonds are now staggered by a quarter, resulting in a stronger bond (the constructional self-weight being distributed over a greater area). This bond, as well as Flemish bond, does not necessarily have to be one brick thick, they can be built using 'snap headers' ie. headers cut to half their length, which give a full brick appearance. They are often used in cavity walls when matching existing solid wall patterns.
Header bond
Header bond (also known as Spanish bond) was a very common bond for bearing walls. It is composed of header bricks, set in rows that are offset half a brick, which produces a solid easy to lay bond which is useful when building circular work. It is the most used bond in historical Spanish brick constructions. Picture shows Header bond.
Flemish bond
Flemish bond, also known as Dutch bond, has historically always been considered the most decorative bond, and for this reason was used extensively for dwellings until the adoption of the cavity wall. It is created by alternately laying headers and stretchers in a single course. The next course is laid so that a header lies in the middle of the stretcher in the course below. Again, this bond is one brick thick. It is quite difficult to lay Flemish bond properly, since for best effect all the perpendiculars (vertical mortar joints) need to be vertically aligned. If only one face of a Flemish bond wall is exposed, one third of the bricks are not visible, and hence may be of low visual quality. This is a better ratio than for English bond, Flemish bond's main rival for load-bearing walls.
A common variation often found in early 18th century buildings is Glazed-headed Flemish Bond, in which the exposed headers are burned until they vitrify with a black glassy surface. Monk bond is a variant of Flemish bond, with two stretchers between the headers in each row, and the headers centred over the join between the two stretchers in the row below.
Garden wall bond
These bonds are variations on normal bonds. They use a high proportion of stretchers, and hence require fewer facing bricks than normal bonds. This makes them less sturdy, but cheaper to lay. As such they are most commonly used for garden- and other non-load-bearing walls.
Rat-trap bond, also known as Chinese bond, is a type of garden wall bond in which the stretchers and headers are laid on their sides, with the base of the stretcher facing outwards. This gives a wall with an internal cavity bridged by the headers, hence the name. The main advantage of this bond is economy in use of bricks, giving a wall of one brick thickness with fewer bricks than a solid bond. Rat-trap bond was in common usage in England for building houses of fewer than 3 stories up to the turn of the 20th century and is today still used in India as an economical bond, as well for the insulation properties offered by the air cavity. Also, many brick walls surrounding kitchen gardens were designed with cavities so hot air could circulate in the winter, warming fruit trees or other produce spread against the walls, causing them to bloom earlier and forcing early fruit production.
Herringbone bond
When bricks are laid on alternating angles, it is called a Herringbone. This is primarily a decorative style, more often used for paving or fireplace reflectors than for walls. It is generally considered unsuitable for load-bearing structures, but may be found as infill in traditional timber framedbuildings. This style is also sometimes called by its Latin name: Opus spicatum.
Basket bond
This decorative pattern imitates the weave of a basket. It's also sometimes called a basket weave bond, and there are many variations on the weave pattern, some very elaborate.
American bond
American common bond is made by laying the courses of headers where they are separated by approximately five to seven courses of stretchers. On occasion American common bond can be found with nine courses of stretchers between courses of headers. Scottish bond has one row of headers to five of stretchers.[1] The stretcher courses are most often an uneven number.
Brickwork Tools
Brick Trowel
brick trowels come in many shapes and sizes ranging between ten and fourteen inches. One side of the trowel in good quality trowels is hardened, you can get both left and right handed trowels but this is uncommon nowadays, the reason they are hardened is that they can beused for rough cutting, however this use is not advised for the beginner. The measurements of the actual blade size andthe width of trowel also varies and people new to the trade will often find that a narrower trowel is easier for them to use.
Pointing Trowel
this is a smaller version of the brick trowel but with both edges being straight, these are used for certain types of pointing or to add a finish to the brick work.
Spirit Level
Spirit Level This will be the most expensive part of the tool kit. It is used to check the brickwork as it is laid to check that the bricks are level (horizontal) and plumb (vertical). The Typical sizes for everyday work are 900 or 1200 millimeters long.
Boat Level
A Boat Level is Similar to the Spirit Level above, it has two bubbles, (one for levelling, the other for plumbing) but is smaller. It is used for mainly decorative panels and soldier brick courses.
Line and Pins
These are used as the wall is being built up to provide a guide for the bricks between the pins. The pins are tapered at the ends to allow them to be inserted into mortar joints. It is important that the line is kept free of knots and clean of mortar.The line is also used (without the pins) with the corner blocks (below) where a wall is being built up between two corners.
Corner Blocks
Corner Blocks are used in pairs as an easy method of holding the line up between the corners of the brickwork.
Tingle Plate
Tingle Plate's are used for holding the line up over long lengths of walling to remove any sagg. The plain end is held down with a brick on top of laid courses and the string line is threaded through the cut outs. you can get small plastic "throwaway" ones as apposed to the large metal ones.
Club/lump Hammer
Used with either a bolster or cold chisel. For cutting or removing bricks from existing brickwork.
Bolster
Used for cutting bricks. Eye protection must be used at all times it is used. The end of the handle should never be allowed to mushroom. The handle end should be kept free from mushrooms by a grinding wheel which can also be used to keep the cutting edge sharp.
Cold Chisel
Similar to a bolster but with a smaller blade, used more often for cutting into brickwork after it has been laid e.g. for letting in services. Again maintenance and safely procedures should be followed the same as for the bolster.
Gauge Rod
Inexpensive as you make it yourself. A length of timber with the vertical spacing of the bricks marked along one edge. Used when working from both ends of a wall to ensure that the courses are equal.
Brick Bat Gauge
Another inexpensive tool which is able to be made. Easy to use when a lot of cutting is required and maintains a regular size to the cuts. The one illustrated is made for the three most basic cuts used. Half bat, three quarter bat and closer.
Brick Hammer and Skuch
Brick and Skuch are two similar types of hammer, one with a fixed head, the other with detachable blades. When the teeth have worn down, the blades can be renewed. They can be used for a number of jobs:
- Tidying the edges of cuts to leave a clean edge.
- For what is known as chasing, i.e. letting cables into walls before plastering - although electric chasing tools are now more commonly used.
Jointing Tools
Used for putting a finish to the joints in brick work. A half-round joint is also known as a bucket handle finish.
Terminology
- Bat
- A brick cut in half or quarter along the short face.
- Closer
- A queen closer is brick cut in half down the long face. Used in corners of English or Flemish bond.
- Header
- Brick is laid in a wall, usually connecting two rows of a double wythe wall. The smallest end of the brick is horizontal, aligned with the surface of the wall and exposed to the weather.
- Quoin, "coin"
- (or "coin" - are groups of brick that project slightly from the face of a wall at the corner of a building. The pattern often alternates with several courses projecting bricks, and several courses that are aligned with the wall. The pattern of projecting quions often alternates with the brickwork on the other side of the corner.
- Rowlock or 'Brick on edge' (UK)
- A complete course of brick laid on its side, with the shortest end of the brick exposed and vertical. Commomly used on the top course as a coping for garden walls.
- Sailor
- Brick laid vertically on its end with the largest, broad face exposed.
- Shiner
- Brick laid on edge like a sailor, but the broad face is set horizontally.
- Soldier
- Often a complete course of brick laid on end vertically, with the narrow side exposed in the face of the wall.
- A "standing soldier" is the most common way of setting the soldier brick on end that is flush with the wall. A "walking soldier" is a soldier course laid so the bottom edge of the brick is sticking out to about an inch. Usually alternating every other brick with a standing soldier, but other variations have been seen.
- Stretcher
- Brick (or other masonry block) laid horizontally in the wall with the long, narrow side of the brick exposed. Commonly used for English bond and Flemish bond pattern, alternating with header bricks.
See also
References
External links
- DIYinfo.org's Brick Laying Wiki - Heaps of practical information on laying bricks
- Brick patterns for wall and pavement
- National Concrete Masonry Association
- Details on turning corners and adjoining walls by the use of bats and queen closers
- Brickwork Bonds and net quantities per m³ Diagrams of most types of bond
- Good photos and discussion of English brickwork and its history
This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)
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