Index

26 August 2011

Home Maintenance


Front Cover of book
Home Maintenance Manual

by Simon James

Published by
Sphere Books Limited in 1983

ISBN 0 7221 0582 7

As the title implies, this is a general DIY book with examples from all the major trades
Items relating to brickwork are shown below

How to mix Concrete
Images and text from page 186-187

Mix the sand and aggregate in the correct proportions
Measure out the cement and add this to the heap


Image from page 187

Make a crater in the middle of the heap
and pour in water as required


Image from page 187
Mix well with a spade, turning constantly
until it is all completely wet


Image from page 187
The mix should be stiff enough to hold ridges
made with the edge of the spade

If more water is required, use a watering can
fitted with a rose


Image from page 187

Concrete consists of Cement mixed with Gravel and Sand, called Aggregates, and bound together with water

The gravel, or sometimes crushed stones, is known as a Coarse Aggregate and sand is a Fine Aggregate

Portland cement is used for most concretes, though there are fast-setting cements available which should be used if there is a risk of heavy frost before the cement has had time to harden

Frost is concrete’s worst enemy, it will cause it to disintegrate and so it is advisable not to carry out any concreting work during the winter months, unless absolutely necessary

When buying aggregate, ask for 'all-in' which has the sand and stones already mixed. For small jobs you can buy ready-mixed aggregate and cement, all you need to do is add the water

It is important that only clean, fresh water is used. Rainwater may contain impurities which will affect the setting. The amount of water is also important - too much will produce a weak concrete that will shrink and crack as it sets

The aggregate and cement should be mixed in proportions suitable for the work to be done. For heavy-duty work, such as a driveways, floors or fence posts, use 1 part of cement to 4 parts of all-in aggregate. Paths can be repaired with a mix of 1 part cement to 3 parts aggregate

It is the coarse aggregate that gives concrete, its body and strength, but this is not needed for filling cracks and holes and a mix of 1 part cement to 3 parts of coarse sand is sufficient for this work

When mixing concrete measure out the aggregate first, then add the cement. Try not to make more than is necessary for the job. It is better to make several mixes than to overestimate and have concrete left over

Add water in small amounts until you have a workable mix, with no dry aggregate. For the best results use a watering can fitted with a rose; this will ensure an even spread of water

Concrete made with Portland cement takes about four days to set in warm weather, but it should not be allowed to set too quickly. Cover it with damp sacking or polythene sheets or a layer of damp sand

Boards placed on bricks and laid across a concreted path or driveway will prevent dogs, cats and birds leaving their footprints

For mending cracks in a concrete path or drive, use 1 part cement, 3 part sand and add a PVA bonding agent that will give a good bond between the old and new concrete

How to mix Mortar
Images and text from page 188-189

First mix the ingredients, dry - sand, cement, and lime if required. Then make a crater in the top of the heap. Add water from a watering can and rose


Image from page 189
Mix thoroughly until all parts of the heap are consistently wet. The mix should be stiff enough to be sliced with a spade or trowel


Image from page 189
Mortar is used chiefly for bricklaying and repointing; that is, repairing crumbling joints in brickwork. It is also used for rendering outside walls

The ingredients for brickwork mortar are graded sand, Portland cement or lime, and water

Choosing the right ingredients is essential for making a good mortar. Sand, for example, should be well graded, which means that the grains vary in size from coarse to fine

Well graded sand gives a strong mortar mix, whereas uniform sand (where the grains are all of equal size) results in a weak, porous mix

A sand/cement mortar mix, though strong, tends to crack as it dries out. A sand/lime mix sets slowly and does not crack but it makes a weak joint. A compromise, therefore, is to use all three ingredients

Another ingredient, particularly useful for rendering, is masonry cement. It makes a highly workable mix with good plasticity

A mortar with good plasticity is smooth and therefore easy to mix and point. Plasticizers are available in powder or liquid form and break down surface tension. They can be added to cement/sand mixes

Another additive that can be used when pointing is a vegetable dye or ready-mixed coloured compound for picking out the joints against the colour of the brickwork

A golden rule for using mortar is that the mix should be no stronger than the materials with which it is to be used

For brickwork, laying and pointing, the usual mix is 1 part cement, 1 part hydrated lime and 6 parts of sand

When adding water, avoid too wet a mix as it will be difficult to pick up on the trowel and will slide off

Mix the cement, lime and sand thoroughly before adding water. Try to make the mix close to where it is to be used and avoid making more than you will need for each part of a job. The area should be clean - a large piece of chipboard or a square of timber makes an ideal mixing base - so that the mix is not contaminated with particles of soil or dust

Add water sparingly from a watering can fitted with a rose and keep turning the mixture until it is evenly wet. From time to time, stick a trowel into the mix to test it - when it is withdrawn the impression should stay; if the mortar crumbles it is too dry, if it disappears rapidly it is too wet

The table below shows the proportions of cement, sand and lime used for the different requirements

Use of MortarSuitable Mixes
External Brickwork1st White
2nd white
3rd
4th
5th
6th
7th
8th
Summer (no frost)
1 Cement
2 Hydrated Lime
9 Sand

Winter
1 Cement
1 Hydrated Lime
6 Sand
Garden Walls1st White
2nd white
2 Cement
1 Hydrated Lime
9 Sand
Rendering
1st White
1 Masonry Cement
5 Sand
Internal Walls
1st White
2nd white
1 Cement
2 Hydrated Lime
9 Sand
External Blockwork
1st White
2nd white
1 Cement
1 Hydrated Lime
6 Sand
Internal Blockwork
1st White
2nd white
1 Cement
1 Hydrated Lime
9 Sand

Bricklaying
Images and text from page 192-193





Bricklaying is a skill that comes with much practice and experience, and it would be a difficult task for the average handyman to take on a large job such as building a garage or a house extension. Nevertheless there are small jobs eg, bricking in a fireplace, which can reasonably be undertaken

All brickwork, whether a wall or filling in a fireplace, must be bonded. This means simply that the bricks are laid in such a way as to give the structure strength and stability. A wall built with bricks stacked one on top of the other would quickly fall down

For most small jobs requiring a single thickness of bricks, Stretcher Bond is adequate. Each row of bricks is called a course, and in each course the bricks overlap those in the course below.

Two other bonds, called English and Flemish, are used in large structures, but there is also the English Garden Wall bond used as the name implies. This bond is not as strong as English or Flemish but is attractive to look at. It consists of three courses of stretchers alternating with one course of headers. In a header course the bricks are laid across the wall

Another attractive garden wall is made by Open Bond. This consists of courses laid in Stretcher Bond but with spaces the width of a quarter of a brick, called a quarter-bat

A garden wall will need a foundation, which can be made by digging a trench about 1 ft deep and filling it with concrete (1 part cement; 4 parts mixed aggregate)

If the courses are to be laid to a height of about 2 ft (61 cm), you will need to check constantly for level and straightness with a spirit level. Getting the correct level depends largely on using the right amount of mortar between courses, and a little practice may be needed

After mixing the mortar, scoop up enough to load a trowel and make a bed about 10mm thick and lay the first brick flat side down. Butter the end of the next brick to the same thickness and lay it against the first brick. Continue along the course and check for level, tapping down any bricks above the level with the handle of the trowel

Lay the next course in the same way, trowelling mortar into the hollowed top, called the frog of each brick in the course below

At some point you may need to cut a brick, especially when bricking- in a confined space. This is done with a bolster chisel; measure off where the brick is to be cut and mark a pencil line. Hold the bolster at a slight angle along the line, leaning towards the waste section of the brick. Make the cut with a sharp, single blow with a club hammer












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