BRICKWORK IN THE GARDEN - BRICK
Laying bricks is a straightforward process for
any DIY enthusiast. Bricks can add maturity and a
warm effect to many gardens. Learn about brick
The brick walls
of a house have two primary physical functions.
One is to hold up a roof, and the other is to form
a framework around a set number of rooms (a) for
privacy and (b) to stop the wind from getting in.
They are also useful for hanging pictures; and of
course a doorway would not be a lot of use without
A garden wall on
the other hand does not need to have a physical
function. It can simply look nice - just by being
It can also have
functions as well; such as holding a greenhouse
up, retaining a soil bank, forming an edge or
division, housing a BBQ, raising a planting bed,
enclosing the wheely-bin or compost heap
(sometimes one and the same!), helping to provide
a level site for the patio, screening off
neighbours, creating rooms, or simply acting as a
boundary. They are also quite useful for hanging
gates on, and building arches in!
Most garden plans
include a wall, and of course the Victorians loved
their walled gardens and brick laying; or did they
love their gardens walled?
Garden walls have
one disadvantage. They can be expensive. One way
around this is to cut out the middleman - the
bricklayer. (Most of the good ones are busy
building houses again anyway). That means someone
else will have to do the bricklaying - build the
wall - You! (Yes you can).
Most garden walls
are less than a metre high - well within the scope
of any `handy' person. In this article we will be
dealing with the basics to get you up to this
height. In following articles we will be looking
at more substantial, ornate and stone walls.
you start brick laying
All garden walls
should be designed on a piece of paper - a plan.
It may well be that you only want a short straight
wall, and don't see the point of putting a
straight line on a piece of paper. So, let's give
it the `5W' test - What, why, where, when, who?
Why do you need a wall - instead of a fence,
trellis, shrub border or a few planted tubs? Where
is it going to go - will anything be in the way
(Services, tree roots, etc)? Who is going to build
it; order the materials; clean up after you etc?
What is it for - what bricks are you going to use;
there are many types - not all will be suitable.
When are you going to do it - how long will it
take; will you have the time?
On your `master
plan' you should plot the dimensions of your wall,
which will enable you to work out the measurements
for the foundations (footings). Then you can
estimate the quantities of materials you will
require. When designing your wall, aim for
measurements that are in multiples of the size of
bricks or walling blocks that you are going to
use. The sizes are usually quoted as being
`nominal'. This simply means that this is what
they should measure once they are laid with the
recommended 10mm width joint of mortar.
measure 215 x 102.5 x 65mm (8.5 x 4 x 2.5in) but
can vary from brick to brick. With the mortar
joints added, this normally means 4 bricks for
every 900mm (3ft) length of wall and 4 bricks for
each 300mm (1ft) height of wall. Allow 58 bricks
for each square metre surface area of wall (48 per
square yard). You should also allow an additional
5% for cutting and breakages. These quantities are
for a single width wall. For a double wall, you
simply double the quantities. Don't forget to
allow additional bricks for building the piers,
including for any additional height of the piers.
wall is to have an ornamental as well as
functional use, then it will be a good idea
to be aware of the orientation. For
instance, if your house and garden faces
south and you propose to build a wall across
the garden (i.e. from W to E), then the wall
face that you see will effectively face
north. It will get little or no sun, and
could be quite somber in appearance. It
could also `mature' quite quickly, with
algae and other growths.
On the other
hand, if the wall that you see faces East or West,
then a recessed mortar joint would enhance the
brickwork in the morning or evening sun
respectively. If the wall is exposed to the normal
Westerly rain, then a different type of joint is
called for - together with a modified mortar mix.
certain lengths and heights will need to be
strengthened at regular intervals with piers.
These piers will have to be provided for when
constructing the foundations. Even the smallest
single brick-width wall will benefit from piers at
any free standing end.
wall over 300mm (12 inches) height should have
piers at intervals not exceeding 3 metres (9ft
9in). Walls shorter than this will also benefit
from the inclusion of piers. The piers should be
no less than double the thickness of a single
brick wall. They can be simply constructed with
galvanized wall ties, but it is quite easy to bond
a pier into a single brick width wall. There are
several ways of doing this.
dimensions of the wall have been determined
together with the position of the piers, the
foundations can be designed. Everything to do with
`hard landscape' requires suitable foundations.
Walls are no exception, and I make no apologies
for repeating myself: I cannot over-state the
importance of proper foundations.
For most garden
walls, a `strip' footing is used. This is simply a
straight-sided trench filled with concrete.
The trench should
be dug out of firm soil. It should not be dug out
of ground that has been recently filled, such as
is often found on building sites. If your trench
starts to fill with water from surrounding ground,
then expert advice should be sought before
proceeding. This is not likely to be the case in
these days of low water tables.
bottom should be firm base soil. If it is not,
then you will need to dig deeper than the
recommendation and back fill with compacted
hardcore before filling with concrete.
The overall depth
of your trench should allow for the stated depth
of concrete, and also for two courses of bricks to
be laid below ground level. This will enable
planting to be carried out at the base of the
wall, or for paving to be laid right up to the
wall if that is to be the case.
Minimum depth of
concrete = 150mm (6 inches)
trench/footing = 300mm (12 inches)
(Where piers are
to be incorporated - normally double brick width -
then suitable footing (450x450mm) should be
allowed for, and accurately sited within the
wall... (213mm or 8.5 inches)
Minimum depth of
concrete = 225mm (9 inches)
trench/footing = 450mm (18 inches)
(If piers are to
be included, then the concrete pad for the pier
should extend at least 150mm on each side of the
pier. i.e. for a 325mm pier (One and half bricks)
the pad should be at least 625mm (25inches) wide
and for a 450mm pier (Two whole bricks) then the
pad should be at least 750mm wide.
stand-alone piers - pergola, gate supports etc -
the footing pad should be considerably wider than
above and will be covered in a following article.
If you aim to
have the first two courses of bricks below ground
level, then you will need to excavate a further
150mm, to allow for the two courses of bricks and
The concrete for
the footing should be mixed in the volume ratio of
1:6 (Cement to `all-in' ballast). Volumes should
be gauged accurately. The mix must not be sloppy
and wet, refers) but should have the least
amount of water added to the dry mix in order for
it to be workable. An overly wet mix will
considerably weaken the strength of the concrete
footing. A wet mix may be easier to spread,
consolidate, and float-finish to a level, but it
The concrete is
placed into the trench and well compacted with a
punner/rammer to ensure that there are no air
voids within the footing. If your mix has the
right water content, then you can leave a semi
rough surface by tamping with the edge of a board.
This will help to bond the first course of mortar
and bricks to the footing.
Allow three to
four days before starting your brickwork, and
during this time make sure that the concrete is
allowed to cure slowly. Place a sheet of plastic
along the surface and secure with bricks or
boards. The bags from your ballast can be used for
A problem can
occur if building your footings in extremely dry
conditions - seemingly unlikely as I write this.
The dry sides of the trench can draw off the water
from the concrete quite quickly. Concrete should
never be allowed to dry too quickly. Anything that
can be done to keep the surrounding soil moist
will help, though you will not want water lying in
the bottom of the trench. It will also help if you
can spray the setting concrete each day. Do not
On sloping ground
you will need to construct `stepped' footings.
Ensure that any timber shuttering is sturdy enough
to take the weight of the concrete and your
compaction. This also applies, if some of the
footing is above existing ground level. The timber
shuttering must be up to the task of holding the
concrete in place without any bulging or sagging.
LAYING THE BRICKS
You will be
confronted by a huge range of bricks. Not all are
suitable for exterior works, and some may only be
suitable for sheltered positions.
Bricks come in
many colours and textures, and various qualities.
`Facings' are usually suitable for most exterior
work for the `faced' edge is normally water and
frost resistant. `Commons' are for interior work
only. Ordinary quality bricks are suitable for
most exterior situations, but can suffer if
exposed to continual driving rain or severe
frosts. `Specials' or `Best' quality are suitable
for all exterior works including steps and
Before you even
start to mix up the cement mortar for your first
ever course of brick laying, lay out the first
course of bricks without mortar - just to make
sure that it all works out on the ground. Allow
for the mortar joint between each brick. (10mm is
ideal). If it is your first attempt at building a
wall, try a dry run with a few courses. Use your
spirit level in the vertical and horizontal
positions to get used to it. You could even lay a
few courses of a short wall onto a sheet of ply or
hardboard, using a mortar mix. In particular,
build a corner or end section to four courses
high. The mortar can be cleaned off the bricks
once it is semi-dry.
The Mortar Mix
The mortar mix
for laying bricks, should be of the ratio of 1
part cement and 5 parts soft builder's sand (1:5).
In very exposed situations, or for brickwork below
ground level, this mix should be modified to 1:4.
Do not add more cement, thinking that you will
have a stronger job - you will not; in fact it
will be weaker.
Add only enough
water to make the mix firm and pliable, but not
runny. If you bounce a dab on your trowel, it
should not sag and should remain on the trowel
when it is turned upside down. It may help to add
some liquid plasticiser. This will make the mix
easier to work. If you do so, then read the
instructions carefully. Incidentally, all the
mortar colourants that I have used have had a
plasticising effect on the mortar.
For most of my
work, I tend to leave the mortar mix in a
wheelbarrow, moving it to where it is required.
Spot boards are fine for the experienced
bricklayer laying a long row of bricks, but not
too efficient for the more time consuming
ornamental walls. In the wheelbarrow, you can
re-liven the mix from time to time with a shovel
or trowel, adding more water (sparingly) when
required. Do not mix more mortar than you can use
within half-hour and make sure that you have a
uniformly mixed mortar.
By David Hughes -