The Bonding of Bricks

I had to visit Launceston, Tasmania (not the English town of the same name) today and the thought was with me – “Bricks” and the Cycle 365 challenge for May.

Years ago I did an Adult Ed course in bricklaying.  I recall the Instructor making sure we understood that the mortar is there to separate and support the bricks, not to glue them together.  To make a strong wall or building, the bricks have to bond together well – like a football team or army platoon.  The bond formed is what holds things together when the going gets tough!  Unless you are from an Office where Human Resources insists on sending staff on a “bonding exercise” when the slackers and achievers end up even further apart than they were at the start.  Oh the joy of retirement – no more nonsense!!!

Back to bricks.

For the technically minded, the long side of the brick is called the “Stretcher” and the short side the “Header”.  The flat top is called the “Bed”.  I have no idea what the flat bottom is called but I expect bricks have a pet name for it.

To start – the “Stretcher” bond.

A “Stretcher” or “Running” bond comprises bricks laid one on another, making sure the gaps in the next level are spaced half way along the stretchers in the previous row.  Bricks don’t bond very well if laid directly on top of each other – gap above gap.  Cracks quickly appear in their relationship – remember the mortar is not a glue in this marriage!  Even if laid in ‘Stretcher’ mode to promote a better bonding between bricks, troubles can still occur (as in the above picture).  This wall indicates that one of the lower level bricks really didn’t want to be in the group and it is trying to leave.


The above wall is built using what looks like the ‘Flemish Stretcher’ bond.  3 rows of Stretchers and one row of Headers.  Much stronger bonding here as the wall will be double brick, the header rows linking the two stretcher rows and every brick feeling supported in it’s individual task.

This wall has one layer of stretchers and one layer of headers.  English Bond.  Almost.  Some stretcher rows have a header as well.  Just can’t keep these bricks apart they are so bonded.

The above is odd.  Looks like a variant of Monks bond.  One row has two stretchers between headers while the next has three headers between two stretchers.  The thing is these bricks must have a strong bond – they form the lower brick layers for the Post Office Clock Tower and they have been together for nigh on 100 years.

English Bond again – reserved bricks, cool with stiff upper lip.

Examples of missing bricks.  I hope they explained carefully to the rejected bricks why they weren’t being included and what an important role they would play by not being there.  Just like it was explained to me when I was retrenched a few years back!

Above – top level of the old gas works. Gas was produced in this building by heating coal and extracting the gas given off.  The coal gas was then stored in gasometers.  Below – there are many of these windows in the same building but did they used to be openings to let clean air in?  Wikipedia didn’t say.

Finally.  A not-a-brick.  Don’t confuse them – they are interlocking concrete blocks.  Bricks would think that these bond together rather too closely for comfort.  Far too familiar they are.

It was nice to get on the Brompton again for a slow cycle around Lonny.  Must do to again soon.


A bloke cycling in (mainly) Tasmania

8 response to "The Bonding of Bricks"

  1. By: The Navigator Posted: May 15, 2019

    That was very informative – highly educational. Thanks! Who knew bricks could be so interesting!

  2. By: Lednar De Nalloh Posted: May 15, 2019

    I did the bricklaying course too. Done a few walls in the garden, won’t be building a house though.

    • By: Tony Cullimore Posted: May 15, 2019

      I built a fireplace for the wood heater. A professional brick layer was visiting and asked “Who build your fireplace?” When told it was me no further comment was made!!

  3. By: Rich-Illinois Posted: May 15, 2019

    Very interesting and informative.
    Thanks for the info and illustrations of the different patterns of laying brick.
    Im still not clear on the mortar not being a glue but being there to separate and support the bricks. And yet the bricks have to bond together. . . . .
    Im guessing most people think mortar is glue, which apparently it isnt, so how does that work exactly?
    Great to see the Brompton back out and rolling!

    • By: Tony Cullimore Posted: May 15, 2019

      If you have ever tried to remove mortar from bricks to reuse them the comment re “it is not a glue” seems wrong. Bloody hard to get off!

      BUT the purpose of the mortar is more to assist the laying of the bricks level with each other and level in all directions. A dollop of mortar goes on first and then the brick is levelled using eye and spirit level banging it with the trowel, then the excess mortar squished out is removed. Looks easy. For a novice like me it was hard.

  4. By: NancyG Posted: May 20, 2019

    WOW! I had no idea that bricks, and brick laying had so much to know about. I feel I need to take notes so the next time I am at a wall I can impress whomever is with me!! Thanks for this very educational post, I thoroughly enjoyed it and learned so much. We never know how much we don’t know!!

  5. By: gregblood Posted: May 20, 2019

    Amazing. The May brick challenge seems to have been designed just for you. Nobody else here has as much brick knowledge as you do. Great combo of words and pictures to back up your words.

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