Wall Height – Standard Bricks

The table shows the height of walls based on ‘Standard Bricks’ of 230mm x 110mm x 76mm with 10mm mortar joints.

Bricks Wall Height (mm) Comments
1 86
2 172
3 258
4 344
5 430
6 516
7 602
8 688
9 774
10 860  Good Height For Barby
11 946
12 1,032
13 1,118
14 1,204
15 1,290
16 1,376
17 1,462
18 1,548
19 1,634
20 1,720
21 1,806
22 1,892
23 1,978
24 2,064
25 2,150 Min Height Non-Habitable Room*
26 2,236
27 2,322
28 2,408 Min Height Habitable Room*
29 2,494
30 2,580
31 2,666
32 2,752 Typical Upgrade Room Height
33 2,838
34 2,924
35 3,010

*For More on ‘Habitable Rooms’ check this link: Habitable Room

For wall lengths see this link: Wall Lengths

 

Wall Length – Standard Bricks


If you are looking designing at a floor plan it can be useful to think about planning the walls based on brick size.

The table below is based on ‘Standard Bricks’ of 230mm x 110mm x 76mm with 10mm joints.

It provides both the wall lengths, and the opening sizes.

 

Bricks Wall Length (mm) Openings Width (mm)
1.5 350
2.0 470 490
2.5 590
3.0 710 730
3.5 830
4.0 950 970
4.5 1,070
5.0 1,190 1,210
5.5 1,310
6.0 1,430 1,450
6.5 1,550
7.0 1,670 1,690
7.5 1,790
8.0 1,910 1,930
8.5 2,030
9.0 2,150 2,170
9.5 2,270
10.0 2,390 2,410
10.5 2,510
11.0 2,630 2,650
11.5 2,750
12.0 2,870 2,890
12.5 2,990
13.0 3,110 3,130
13.5 3,230
14.0 3,350 3,370
14.5 3,470
15.0 3,590 3,610
15.5 3,710
16.0 3,830 3,850
16.5 3,950
17.0 4,070 4,090
17.5 4,190
18.0 4,310 4,330
18.5 4,430
19.0 4,550 4,570
19.5 4,670
20.0 4,790 4,810
20.5 4,910
21.0 5,030 5,050
21.5 5,150
22.0 5,270 5,290
22.5 5,390
23.0 5,510 5,530
23.5 5,630
24.0 5,750 5,770
24.5 5,870
25.0 5,990 6,010

NB. Maximum dimension between Articulation Joints is 6.00 (see this link: Articulation Joints)

For Wall Heights see this link: Wall Height

 

Ornamental Brickwork

In Australia most brickwork these days consists of large panels of stretcher bond brickwork.

Where there are openings it usually spanned by steel lintels giving a square opening.

I’ve just shown a few examples of a different approach from my recent trip to England.

I wonder how many current Australian Craftsmen would be able to do something like these examples?

Why Do Bricks Have Holes?

The holes are called ‘Core Holes’

Before ‘Core Holes’ were a thing most bricks has a large surface indentation called a ‘Frog’

So here are some reasons for the holes.

  • Better locking in with the mortar. As the bricklayer taps the brick down the mortar squeezes into the holes improving the hold between the set mortar and the brick.
  • Easier to Fire. When the brick is fired in a kiln the holes allow the heat to better penetrate the brick. . . . saves time and fuel.
  • Lighter bricks. Easier on the bricklayer, and trucks can carry more saving material costs.
  • Less material. More savings as it uses less clay

Front Fence Failure

Generally you don’t have to go far to find a front brick fence falling over like this one.

Normally they fall over in the direction of the street.

So why is this failure so common?

Reasons For Failure

  1. People think “It’s only a brick fence” so don’t put a good foundation in, and only make it a single brick thick.
  2. Simple brick construction is fairly brittle when any stress is placed at 90 degrees to the wall face.
  3. Frequently the soil is built up on the garden side of the wall making the wall a retaining structure. with the consequent stresses which can be significant.
  4. If the wall is built on reactive clay the street side of the wall is kept dry by the pavement while the garden side gets water seeping through and can be subject to soil heave.

What You Can Do

  • Construct a substantial foundation
  • Make the wall at least two bricks thick with steel reinforcement built into the wall.

or

  • Consider alternatives like panel fences or hedges

 

Patterned Brickwork

What do you think of patterned brickwork?

I think it can look well if its used with restraint and understanding.

Unfortunately I don’t think this example that I recently saw qualifies.

Those triple block features at the window are supposed to represent Quoins (stone blocks to reinforce corners) . . . .that and the over complex single pattern on the building corners are the opposite of what you would see on a genuine old patterned brick house.

A much better option would be to have the ‘Quoins’ on the corners and a plain brick window edge.

Do you agree? . . or do you think I’m just being picky?

 

Roman Bricks

Do you like the look of the brickwork in this photograph?

It’s known as Roman brickwork as it gives a similar look to the brickwork that was used in Roman Times.

The look also emphasises the horizontal lines in a structure.

A modern Australian Roman Brick is based on the standard brick dimensions (see this link: Brick Dimensions) but is only 50mm tall, rather than 75mm.

The ‘Working Dimensions’ are 230mm x 110mm x 50mm.

Additional Cost

Although the bricks are smaller don’t expect them to be cheaper; you will be paying premium brick prices.

The labour costs will also be between 150% and 200% of the cost of a standard brick wall.

 

Efflorecence

What’s that white powdery stuff that can appear on brickwork?

Well the technical name is Efflorecence

It can also appear on concrete!

What Is Efflorescence, & How Is It Caused?

Basically it is caused by water soluble salts contained in either the mortar, or the bricks.

When any water in the wall (that has dissolved the salts) comes to the surface of these building materials the water evaporates, leaving the salts on the surface.

Although the salts sometimes come from the bricks, more commonly they originate from the mortar.

Although some efflorescence may be as a result of the initial construction water; walls that are regularly wetted can have more persistent  issues, for instance:

  • Uncapped garden walls.
  • Retaining walls.
  • Walls exposed to driving rain.

Efflorescence is more prevalent on South and East facing walls as these are colder so the moisture gets to the face of the wall. North and West facing walls are generally warmer so the water evaporates before it reaches the surface leaving the salts inside the walls.

What Can Be Done To Prevent Efflorescence?

There are several things that can be done to minimise efflorescence including:

  • Overall design to keep water out of the wall structure.
  • Specifying Mortar Joints to keep water off the wall.
  • Protecting bricks from weather before they are laid
  • Specifying low alkali cement.
  • Specifying Washed Sand
  • Using a mortar admixture to minimise the water cement ratio.

Dealing With An Existing Problem

Probably the first step when dealing with an existing problem is ensuring the wall can be kept dry.

As long as there is a path for water to get to the surface it will be very hard to deal to achieve a permanent solution as water will continue to evaporate on the surface bring out fresh salts.

When removing the actual efflorescence its best to try a stiff brush first.

If this doesn’t work you can try hand washing again using a stiff brush. (Although it is tempting to wash the soluble salts off with a pressure washer the water can penetrate into the wall and then as the brickwork dries bring further salts to the service)

The final suggestion is to use a special chemical efflorescence removal chemical. (These tend to be acid based and need to be used exactly as the manufacturers recommend)

 

See Bricks for more posts

 

Brick Ties

Veneer galvanised brick tie

Brick ties, although small, have an important part to play in the structural strength of your new home.

  • In brick veneer construction, ties are used to pass all the sideways forces across the cavity (such as from wind) to the frame.
  • For double brick construction the ties share the forces between the leaves.
  • They prevent lateral movement at expansion and articulation joints.
  • Special ties also connect walls where bonding of masonry is not practical.

Effectiveness

Probably the biggest test of brick walls in Australia was the 1989 Newcastle (NSW) earthquake. . . . Generally brick walls survived well except where there were problems with the ties such as:

  • Rusted through galvanised ties;
  • Ties not properly connected;
  • Missing ties;
  • Incorrect ties used.

Types

Ties are available in a wide range of types and in various strengths such as heavy, medium and light duty. (Ancon Building Products have a very informative downloadable guide)

The tie illustrated above is a galvanised stamped steel plate tie, used to connect the brickwork to a frame. The tie is nailed to the frame (through the hole at the top) and the corrugated end is incorporated into the mortar joint of the brickwork. The section of tie which spans the cavity is shaped to shed water.

In the case of a double frame construction a wire tie with loops at each end, or a figure of 8 shape,are the common choices of ties.

Common Materials are:

  • Galvanised Steel – Most common type.
  • Stainless Steel – For high exposure locations or very long life. (Seem expensive but only a small component Thof overall building  cost)
  • Plastic – Mainly for acoustic applications.

Spacing

Check with your Structural Engineer but for a typical medium duty application:

  • Vertical Spacing 600mm  but 300mm around openings
  • Horizontal Spacing  600mm for Double Brick  OR every main stud for Brick Veneer (normally 450mm for external walls and 600mm for internal walls

More information can be found in the Australian Standard AS3700 .

 

See Bricks for more posts

 

Retaining Walls – Besser Blocks

If  you want a rendered surface on your retaining wall one of the best ways of achieving this is by using ‘Besser Blocks’.

These are hollow concrete blocks which are designed to incorporate steel reinforcement within the block.

A few  issues when building these walls are:

  • Don’t skimp on the foundation. Even a 600mm high wall will need a concrete foundation 600mm wide by 250mm deep.
  • Make sure that the cement grout is well packed around the steel reinforcement.
  • Buy some of the yellow safety caps you see here to put over  the reinforcement bars and ‘Keep Yourself Safe.
  • Don’t backfill behind the wall for at least a week


As well as free standing retaining walls Besser Blocks are also used as basement walls and to provide structural strength for external walls when building against a slope.

This photograph shows a typical example where the Besser Block wall will provide the external wall of a garage. ( You can also see the builders plastic which will form part of the ‘tanking’ to keep damp from passing through the wall)

 

See Retaining Walls for other  solutions to slopes