BRICKLAYING the basics

There’s a lot in bricklaying that you only really pick up with practice. But there are some rules which can guide you every step of the way. Understanding bricks themselves, the right way to mix mortar and how to use the trowel correctly will help you achieve a result to be proud of.

Rickwork is made up of two things: the bricks, and the mortar which forms the joints. Building a wall that’s going to last needs careful attention to both, and the first thing is to choose the right bricks for the job.

Know your bricks

There are three groups of clay bricks: 1 Common bricks have no special finish because they are made to be used where they will not be seen or be subjected to major stress or load. They are mostly used in situations where they will be covered by paint, plaster, cladding, rendering etc. They are a relatively inexpensive brick and are usually a rather patchy pink in colour. 2 Facing bricks come in a variety of colours and textures for they are made to be displayed indoors and out. Also called they are capable of bearing heavy loads. If classed as it means they can be used for most projects, but in very exposed conditions outdoors will need to be protected by a damp proof course at ground level (either a course of engineering bricks, see below, or a layer of bituminous felt) or with a coping above to prevent the bricks becoming saturated with rain. Without this protection they are liable to be affected by frost which would cause disintegration. Facing bricks are suitable for use in exposed places or where great strength is needed, eg, for paving, retaining walls, garden walls and steps. 3 Engineering bricks are smooth and dense, designed to be used where strength and low water absorption is essential – for example in foundation courses (thus providing a damp proof course for a wall or planter) and load bearing walls.

Another type of bricks completely are the These are flint/lime bricks which are whitish when steam-hardened in an autoclave (they aren’t fired like clay), but these are available in many colours because they take pigment well. They absorb moisture easily, so must never be laid with a mortar that doesn’t contain a plasticiser. They can be used in just the same way as clay bricks. Like engineering bricks, they are also more regular in shape and vary less in size than ordinary bricks.

Brick types

Bricks also vary in their character as well as their composition: they may be solid, perforated or hollow, but most fall into the solid category. Even bricks with small or large holes in them (these are also known as cellular) are classed as solid so long as the perforations do not exceed 25% of the total volume. The same is true of bricks with a shallow or deep indentation known as a As well as making the bricks lighter, perforations and frogs give bricks a better key( ie.the mortar is better able to bond them together). Bricks are measured in two ways: when they come from the works the actual size is 215mm long, 102.5mm wide and 65mm deep; the format size, however, is the one used for calculating the number of bricks you need. This needs an allowance of about 10mm added to each of these dimensions for the mortar joints – ie, 225mm long, 113mm wide and 75mm deep. Bricks are also made in special shapes and sizes for particular uses (copings, bullnose and angles are some examples).

Storing bricks

As all bricks (except engineering bricks) are porous, they should be stacked on a level area away from damp, otherwise long after you’ve used them the mineral salts inside the clay will stain the surface with an unsightly powdery white deposit (known as In the garden, put bricks on planks or a metal sheet and cover them with plastic sheeting. Apart from anything else, bricks which are saturated with water are hard to lay and will prevent a satisfactory bond between bricks and mortar.

Mortar for bricklaying

Cement and sand made into mortar with water will set quickly, but is liable to create a crack between the mortar and the brick if it shrinks during drying. The ideal mortar, in fact, doesn’t set too quickly, doesn’t shrink much and can take up settling movements without cracking. There are two ways of making a mortar like this:.

– The first way is by adding hydrated lime to the mix. This makes the mortar more workable and smooth (or ‘buttery’ as the experts say).

– The second is by adding a plasticiser – a proprietary liquid or powder. Air bubbles are formed which provide spaces for the water to expand into, thus preventing cracks.

– Basic to mortar is cement. This acts as the adhesive, binding the particles of sand together. Ordinary portland cement is the one most commonly used.

• Fine sand is used for mortar to give it its correct strength. Use clean builder’s sand (also known as ‘soft’ sand) which does not contain clay, earth or soluble salts (these can lead to efflorescence).

Buying the materials

Cement is usually sold in 50kg (112lb) bags, although you may also find smaller sizes. Sand is sold by the cu metre (1V3 cu yd) and in parts of a cu metre. To give you a sense of scale, a cu metre of sand weighs about 1,500kg (IV2 tons) — a very large heap. Both are usually bought from builders merchants, where you can also buy lime or proprietary plasticisers. Alternatively you can buy special masonry cement which has a plasticiser already in it and only needs to be mixed with sand and water.

Proprietary plasticisers are available in 5kg containers and you will have more than you need if you’re only doing a small job.

– only a capful or two for each bucket of cement. But always follow manufacturer’s instructions for use. Hydrated lime is a powder bought in 25kg bags.

Dry ready-mix mortars are also available with all the necessary ingredients ready mixed.

– so you just add water. Although more expensive than buying the sand and cement separately, it’s a convenient way of buying for small projects. Bags usually come in 10kg, 25kg, 40kg and 50kg sizes. Alternatively, you can buy bags in which the cement is packaged separately from the sand.

Remember that it’s always better to have a little more than you need — so be generous in estimating , tap it frequently to disperse any trapped air.

– Mortar that has begun to set is no use. Any not used within 2 hours of the wetting of the cement should be discarded – if used it would dry too quickly and would not give the required strength to the brickwork.

– The sand and cement have to be thoroughly mixed before any water is added. Turn mixture over and over with the shovel until the pile is a consistent colour all through. The same rule applies to dry-mix mortar.

– When mixing in water, make crater on top of the pile, add some water and bring dry materials from sides to centre. Turn over whole pile several times, make another crater and repeat until mixture has a consistency which will hold the impression of the fingers when squeezed, or the impression of the trowel point.

– As builders’ sand is rarely dry it is not possible to know how much water will be needed to achieve the right consistency. Using a small container such as an empty tin will give you more control than using a bucket – and add water bit by bit.

The vital bricklaying tool

The trowel is the tool which makes the job, and no other tool can be substituted for it. A bricklayer’s trowel is heavier and less flexible than any other trowel, and can be used to pick up and smooth down a required amount of mortar. Brick trowels can be bought in various blades sizes (from 225 to 350mm, or 9in to 14in) but the easiest to handle is the 250mm/10inone.

Brick trowels are roughly diamond shaped with a sharp point at the end opposite to the handle. The left side has a straight edge for scooping up mortar; the right side has a slight curve used for cleaning up the edges of bricks and for tapping the brick down into the mortar to level it. These are reversed in left-handed trowels.

Professional bricklayers use the curved edge of the trowel to cut bricks, but a more accurate and cleaner cut can be made with a brick hammer and bolster chisel. The trowel has a wooden handle raised slightly above the diamond, and at an angle to it to prevent you brushing your knuckles on the bricks as you are working. Getting the feel of the trowel and handling it properly is the key to good brickwork.

The trowel must be manipulated so that the mortar is scooped up in what’s called a ‘pear’ or ‘sausage’ shape and placed on the bricks. This action is one that needs a lot of practice, for mortar that isn’t compact is hard to manoeuvre and won’t go. Where you want it to.

Practice routines

Make up a small amount of mortar (or 1 part of lime to 6 of sand, plus water to make it pliable) and practise combining it with bricks before you undertake a bricklaying project. The bricks can be scraped off within 2 hours (before the mortar sets). You have longer with lime mortar. The ‘sausage’ or ‘pear’ is the basic shape of mortar lifted onto the trowel. The following sequence is worth practising over and over until it becomes easy to do. Chop down into the mortar and draw a slice of it towards the edge of the board. Move the trowel to and fro, along the length of the slice, pressing the body of the trowel on to the mortar till you have shaped the back of the slice into a curve – the mortar should be smooth and have no cracks.

Now sweep the trowel underneath the curved slice and load it on to the trowel, it will either look like a sausage or a pear, hence the name. Put it back on the spot board, shape it again, then sweep it up ready for placing. This amount of mortar should give you a 10mm thick bed for two stretchers. Hold the trowel parallel to the course, then, as you draw it back towards you, lift and jerk it slightly so the mortar rolls off gradually in a smooth elongated sausage. Press the mortar along the middle with the point of the trowel so a furrow is made in the mortar. When you place a brick on it a small amount of mortar should ooze out.

HOW MANY BRICKS?

For a straight run of walling, remember.

– One brick length + one joint = 225mm.

– One brick height + one joint = 75mm So for each metre of wall length you need 4.5 bricks; for each metre of wall height you need 13.3 bricks.

Example: a wall 4 m long and 2 m high needs 4 x 4.5 = 18 bricks in each horizontal course, and a total of 2 x 13.3 = 27 courses (to the nearest whole number). 18X27 = 486 bricks in total.

On more complex structures, dry-lay the first course of bricks and count how many are required. Then multiply this number by 13.3 for each metre of height required.

HOW MUCH MORTAR?

For small jobs: buy dry ready-mixed mortar, available in 10kg, 25kg and 50kg bags. A 50kg bag makes enough mortar to lay 50-60 bricks.

For larger jobs: it’s more economical to buy materials separately and mix them up yourself. Here’s how they are sold:.

– Cement — usually in 50kg bags.

– Lime — usually in 25kg bags.

– Sand — by the or whole cu m.

– Plasticisers — usually in 5kg containers

MORTAR MIX

Measure ingredients by volume, using a stout bucket or similar container. For general brickwork above ground level, mix: 1 bucket ordinary Portland cement 1 bucket hydrated lime 6 buckets soft sand

– Replace lime with proprietary liquid plasticiser, added according to manufacturers instructions, if preferred.

– One 50kg bag of cement mixed in the above proportions will give enough mortar to lay about 450 bricks.

TIPS: MORTAR MIXING

The amount of water you add to give the right consistency depends on how damp the sand is. As a rough guide allow 1 bucket of water for each bucket of cement. Remember:.

– always add water gradually, never all at once, mixing after each addition

– always use mortar within 2 hours of mixing; it cannot be reconstituted once it has begun to set.

Joints in brickwork

Bricks are laid with both horizontal and vertical joints to keep the bricks apart. After the excess mortar has been removed from the face of the bricks (and behind), the joints can be finished in various ways – for an attractive effect as well as for protection against the weather. Coloured mortar is a specially prepared dry mix to which only water needs to be added. Pigment can be bought to colour your own mix of mortar but it can be difficult to obtain the same colour for each batch.

Making a cross joint

Sometimes ‘buttering’ is used to describe the technique of coating the end of a brick with mortar to form the vertical joint. Sweep up enough mortar to cover about a third of the trowel. Now sharply flick the trowel so the mortar lifts up, then falls back onto the trowel, (this squashes out air and makes the mortar ‘sticky’). Hold the brick at a slight angle, then scrape the trowel against the bottom edge. Use the trowel point to flatten and level the mortar on the header – it should be 10mm thick.

Cleaning off

The other important trowel action is removing excess mortar from the side of the bricks as you lay them. Cut the mortar off cleanly by firmly lifting the trowel upwards (if you do it horizontally it will smudge the bricks). This leaves a flush joint.

Tricks or bad habits?

Bricklayers will often add a few squirts of washing-up liquid to the water when mixing mortar. This on-site plasticiser. Used instead of lime or a proprietary plasticiser, is not added in any precise manner. Although it might make the mortar more pliable it could also weaken it. And how much is a squirt anyway? If you want a pliable mix, buy a proprietary plasticiser additive, or ready-mix with it already added.

– The shovel is frequently used as a measuring stick when mixing mortar, and there’s no doubt it’s an easy way of propor-tioning the ingredients. It can, however, give wildly inaccurate results. A mound of powdery cement won’t sit on a shovel in the same way as sand will. So measurement should always be by volume. A bucket is ideal for most quantities – although if you’re only making a very small amount use a small metal container instead.

– The curved edge of the bricklayer’s trowel will effectively cut bricks when wielded by a professional. Apart from doing a great deal of damage to the trowel (the edge of which is needed for the upward sweep required to remove mortar from brickwork), it is easier to cut bricks on a sandy or soft ground with a bolster chisel and a hammer.

Protecting brickwork from damage

As soon as you have finished bricklaying, and you’ve cleaned off and finished all the joints, it’s worth taking a few simple precautions to protect your work until the mortar has set and it is able to take care of itself.

The biggest enemy is rain. A heavy downpour could wash mortar out of freshly-pointed joints – which you would then have to re-point – and stain the face of the brickwork. Such stains are particularly difficult to remove except by hosing and scrubbing. Furthermore, if your brickwork is set on a hard surround – a patio, for example, or alongside a path – rain could splash up from the surface onto your brickwork, again causing staining and erosion of mortar joints at or near ground level.

So on small projects it’s a good idea to cover your work, at least for 24 hours or so, until the mortar has had time to set to something like its final hardness. Drape polythene or similar water-proof sheeting over the brickwork, anchoring it on top with several loose bricks, and drawing the sides of the sheeting away from the face of the brickwork before anchoring them at ground level a foot or so away from the wall. In windy weather, lay a continuous line of bricks, or use lengths of timber, to prevent the wind from whipping underneath the sheeting.

Remember that until the mortar has hardened any knocks will displace bricks and break mortar joints. Corners are particularly prone to knocks and accidental collisions. So it’s well worth erecting some kind of simple barricade in front of the new work for a day or two.

Building a brick planter

You can build a brick planter almost anywhere. It only needs to be about 6 or 8 courses high, so foundations are not a great problem. An existing concrete patio. Level crazy-paving or even paving stones wil usually be perfectly adequate. The only important thing is that the base is firm and level – if it isn’t you have to make adjustments with your first course of bricks.

The planter illustrated here is exactly 7 bricks long, two bricks deep and 6 courses high. In total 96 bricks were used and approximately 80 kg of mortar (bought as dry ready mix). The bricks are facing bricks, chosen for their colour and slightly rough texture. The bonding (the way each course overlaps the one underneath) was an ordinary stretcher bond. At the corners, a single brick length divides the two long walls. So the principles of building are exactly those of building any simple wall – the only difference being that 3 vertical joints in the first course were opened up to act as drain holes.

MATERIALS

Bricks: you’ll need 100 bricks, choose faced or facing bricks or even special quality to harmonise with existing brickwork.

Mortar: buy two 40 or 50kg bags of dry ready-mix which includes its own plasticiser. Or 100kg of builders sand, plus 20kg of ordinary portland cement and plasticiser (available in small containers in many builders merchants) or an additional 20kg of hydrated lime. Mix up in the proportions of 6 parts sand to 1 part cement plus plasticiser or 1 part hydrated lime.

Leaks in domestic plumbing systems have a nasty habit of happening at the most inconvenient of times, often when it isn’t possible to carry out a proper permanent repair. What you need is a plumbing emergency first aid kit, and there are now several proprietary products available that will at least enable you to make a temporary repair and get the water flowing again.

With any leak, the vital first step is to stop the flow of water. Even a small leak can create a surprisingly large pool of water in no time. Stopping the flow in any pipe is relatively easy provided that you know the locations of the various stop-taps or valves that isolate parts of your water system, or cut it off completely from the mains supply.

Water comes into the house through a pipe known as the rising main, and because

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