CONSTRUCTION AND THE BUILT ENVIRONMENT

Transcription

1 CONSTRUCTION AND THE BUILT ENVIRONMENT endorsed for

2 Brickwork and Blockwork Operations 17 1

3 UNIT 17 Brickwork and Blockwork Operations Introduction A bricklayer s skills are essential to the construction of high-quality buildings. Facing brickwork can make houses and other buildings attractive, while reliable blockwork is a fundamental part of the structure of a building. By practising the manual skills that are required, you will improve the quality of the brickwork and blockwork that you can produce. Brickwork needs to be clean and free from any mortar spots, and laid level with all the cross joints vertical. You need a great deal of skill to achieve this. Bricklayers often work in teams of two bricklayers and one bricklaying labourer. The labourer is responsible for loading bricks and blocks onto the working area, and for mixing the mortar. Teamwork is therefore essential to ensure safety, speed and quality. It is very rewarding to leave your mark on the world, and a bricklayer can achieve this in a building that will stand for hundreds of years. Assessment : This unit will be assessed through a series of practical assignments that will be set and marked by your teacher/tutor. Learning aims In this unit you will: A explore health and safety regulations and legislation requirements in brickwork and blockwork operations B demonstrate practical skills and safe techniques to construct brickwork walls C demonstrate practical skills and safe techniques to construct blockwork walls. I found this unit really inspiring, so I did two weeks work experience as a bricklayer after finishing my practical assignment. I enjoyed working outdoors on construction sites, and no two days were the same. Even in two weeks I could see that we were bringing a building out of the ground it s a really rewarding process! Aaron, 16-year-old aspiring bricklayer 2 BTEC First Construction and the Built Environment

4 UNIT 17 Brickwork and Blockwork Operations BTEC Assessment Zone This table shows what you must do in order to achieve a Pass, Merit or Distinction grade, and where you can find activities in this book to help you. Assessment criteria Level 1 Level 2 Pass Level 2 Merit Level 2 Distinction Learning aim A: Explore health and safety regulations and legislation requirements in brickwork and blockwork operations 1A.1 2A.P1 English Identify the requirements of a given health and safety regulation that applies to employees carrying out brickwork and blockwork tasks. Describe the health and safety requirements for employees, employers and contractors when performing a practical task in brickwork and blockwork. See Assessment activity 17.1, page 12 2A.M1 English Explain the health and safety requirements on employees, employers and contractors for a practical task in brickwork and blockwork. See Assessment activity 17.1, page 12 Learning aim B: Demonstrate practical skills and safe techniques to construct brickwork walls 1B.2 Maths 2B.P2 Maths Select the resources and jointing techniques required for a specified task in brickwork, to include: scheduling the resources. 1B.3 Maths 2B.P3 Maths Set out and construct one brick wall to given specifications with a minimum height of six courses (450 mm) with guidance: with the brickwork dimensionally accurate to a tolerance of ± 10 mm per m height and length complying with safe working practices, including the use of personal protective equipment. Select the resources and jointing techniques required for a specified task in brickwork, to include: calculating the resources required scheduling the resources. See Assessment activity 17.2, page 20 Set out and construct one brick wall to given specifications with a minimum area of 1 m² and a minimum height of nine courses (675 mm): with the brickwork dimensionally accurate to a tolerance of ± 10 mm per m height and length complying with safe working practices, including the use of appropriate personal protective equipment. See Assessment activity 17.2, page 20 2B.M2 E Maths Discuss the resources and jointing techniques required for a specified task in brickwork, to include: their advantages and disadvantages the resource calculation, including allowances for wastage scheduling the resources. See Assessment activity 17.2, page 20 2B.M3 Maths Set out and construct one brick wall to given specifications with a minimum area of 1 m² and a minimum height of nine courses (675 mm) with an appropriate joint to both faces: with brickwork plumb to a tolerance of ± 10 mm per m height with brickwork dimensionally accurate to a tolerance of ± 10 mm per m height and length with face plane deviation accurate to ± 10 mm complying with safe working practices, including the use of appropriate personal protective equipment. See Assessment activity 17.2, page 20 2A.D1 English English Justify the health and safety requirements in use for a practical task in brickwork and blockwork. See Assessment activity 17.1, page 12 2B.D2 Maths Set out and construct one brick wall to given specifications with a contrasting or recessed bricks central feature, a minimum area of 1 m² and a minimum height of nine courses (675 mm) with an appropriate joint to both faces: with brickwork plumb to a tolerance of ± 5 mm per m height with brickwork dimensionally accurate to a tolerance of ± 5 mm per m height and length with face plane deviation accurate to ± 5 mm complying with safe working practices, including the use of appropriate personal protective equipment. See Assessment activity 17.2, page 20 3

5 Assessment Zone UNIT 17 Assessment criteria Level 1 Level 2 Pass Level 2 Merit Level 2 Distinction Learning aim B: Demonstrate practical skills and safe techniques to construct brickwork walls 1B.4 Maths 2B.P4 Maths Undertake a specified dimensional quality control check on the completed brickwork, with guidance. Undertake and record dimensional quality control checks on the completed brickwork, to include: length (including error) height (including error) level plumb face plane deviation. See Assessment activity 17.2, page 20 Learning aim C: Demonstrate practical skills and safe techniques to construct blockwork walls 1C.5 Maths 2C.P5 Maths Select the resources and jointing techniques required for a specified task in blockwork, with guidance, to include: scheduling the resources. 1C.6 Maths 2C.P6 Maths Set out and construct blockwork walls to given specifications, with guidance: with a minimum height of three courses (675 mm) complying with safe working practices, including the use of personal protective equipment. Select the resources required for a specified task in blockwork to include: calculating the resources required scheduling the resources. See Assessment activity 17.3, page 23 Set out and construct blockwork walls to given specifications, to include corners and junctions, with a minimum height of four courses (900 mm): with the blockwork dimensionally accurate to a tolerance of ± 10 mm per m height and length complying with safe working practices, including the use of appropriate personal protective equipment. See Assessment activity 17.4, page 24 2C.M4 English Maths Discuss the resources required for a specified task in blockwork to include: their advantages and disadvantages the resource calculation, including allowances for wastage scheduling the resources. See Assessment activity 17.3, page 23 2C.M5 Maths Set out and construct blockwork walls to given specifications, to include corners and junctions, with a minimum height of four courses (900 mm): with blockwork plumb to a tolerance of ± 10 mm per m height with blockwork dimensionally accurate to a tolerance of ± 10 mm per m height and length with face plane deviation accurate to ± 10 mm complying with safe working practices, including the use of appropriate personal protective equipment. See Assessment activity 17.4, page 24 2C.D3 Maths Set out and construct blockwork walls to given specifications, to include corners and junctions, with a minimum height of four courses (900 mm): with blockwork plumb to a tolerance of ± 5 mm per m height with blockwork dimensionally accurate to a tolerance of ± 5 mm per m height and length with face plane deviation accurate to ± 5 mm complying with safe working practices, including the use of appropriate personal protective equipment. See Assessment activity 17.4, page 24 English Opportunity to practise English skills Maths Opportunity to practise mathematical skills 4 BTEC First Construction and the Built Environment

6 Assessment Zone UNIT 17 How you will be assessed This unit is internally assessed through one or two assignments set by your teacher/tutor. These assignments will contain a scenario to help you focus on what to include in any written evidence that you use in support of the grading criteria. A substantial part of the assessment will be on the production of some workshop models in brickwork and blockwork. These will be checked and graded on quality and dimensional checks. The assignments will give you an opportunity to work towards the Merit and Distinction levels for your final grade. These higher grades are awarded on the production of your brickwork and blockwork within the tolerances specified. These have been set to be similar to those you would have to produce in a working environment. 5

7 Learning aim A TOPIC A.1 Health and safety regulations and legislation for brickwork and blockwork Discussion How could you promote safe working practices on construction sites? What hazards might you face when working on ladders? Key terms Toolbox talk a talk given on a construction site by a competent person about a particular aspect of health and safety. Plant construction machinery and equipment that operatives use, for example, a rough terrain fork truck. Method statement an outline of how you will undertake a construction activity, listing the methods you will use, the labour, plant and materials. Introduction Bricklayers often have to work from scaffolding when constructing the external walls of a building. As this is classed as working at height, certain precautions have to be taken to prevent any accidents happening because of falls from height of people or materials. Everyone on site should have a site induction, where they are told about all the hazards they might find in their work area. Regular toolbox talks will also reinforce the safety message. Health and Safety at Work etc. Act (HASAWA) 1974 This is the main piece of important legislation produced by Parliament about health and safety. All of the current health and safety regulations have been developed from this Act. It covers many duties for a number of different people who are involved in a construction project, including: manufacturers and designers employers employees. Employer duties Table 17.1 shows the duties of an employer on a construction site and gives an example of how each duty could be met. Table 17.1 Duties of an employer under HASAWA Duty Ensure the health and safety of all employees. Provide and maintain plant and systems. Provide safe systems of work, including ensuring safety and the absence of risk in connection with the use, handling, storage and transport of substances. Give information, instruction, training and supervision. Produce a health and safety policy (when the employer has five or more employees). Compliance Carry out regular safety inspections and audits of the scaffolding that bricklayers are working on. Hire equipment, such as a forklift to lift bricks onto scaffolding. Carry out suitable risk assessments and method statements for work activities involved in bricklaying. Train all operatives for the work they are doing. Write a policy and make it available to the whole workforce. continued 6 BTEC First Construction and the Built Environment

8 Brickwork and Blockwork Operations UNIT 17 Table 17.1 continued Duty Compliance Provide free equipment required for safety. Provide facilities for employees welfare at work. Consult and cooperate with employees on health and safety. Provide all required personal protective equipment (PPE) for free and ensure that it is used. Provide site accommodation, toilets, washing and drying facilities. Elect a site safety representative. Remember Employee duties As an employee, you have certain legal responsibilities to follow under HASAWA. Table 17.2 lists these duties. You must make sure that you work responsibly and behave safely on a construction site. Never do anything you do not feel safe doing. You should always seek help and guidance if you have any concerns about the safety of a task. Table 17.2 Duties of an employee under HASAWA Duty Take reasonable care for the health and safety of yourself and others. Cooperate with the employer to enable the employer to perform or comply with their duties under the Act. Correctly use anything provided for health and safety. Do not misuse or damage anything provided for health and safety. Compliance Always look around to see who is next to you, below you and above you when working on a platform to ensure that your actions will not put their health and safety in danger. Undertake any training, instructions or inductions given by an employer on safety. Wear the PPE provided in accordance with instructions, such as footwear, gloves and a hard hat. Use equipment as trained and report any damage of safety equipment. Control of Substances Hazardous to Health (COSHH) Regulations 2002 The Control of Substances Hazardous to Health (COSHH) Regulations 2002 also contain duties for both the employer and the employee. There are many chemical substances that are used on construction sites. Two are used within bricklaying and blockwork operations. They are: cement this can cause burns when it comes into contact with the skin, as it reacts with moisture from sweating admixtures these chemicals are added to mortar to make it workable, which may cause skin irritation. Employer duties Table 17.3 on page 8 shows the duties of an employer on a construction site and gives an example of how each duty could be met. Did you know? Cement is safe when in a bag and when it is kept dry. Once it is mixed with water, a reaction takes place that can cause burns to exposed skin. Key term Admixture this is a product that you add to the sand and cement. It makes the mix of materials more workable for the bricklayer to use, so it is easier to spread and level. 7

9 TOPIC A.1 Take it further Find a cement safety data sheet online and download it. Use it to find out what precautions have to be taken. Table 17.3 Employer duties under the COSHH Regulations Duty Conduct COSHH risk assessments. Compliance Carry out risk assessments for the use of cement in mortar mixing. Provide control measures to prevent harm to health and maintain them in good working order. Make sure that the control measures are adopted and used. Give information, instruction and training for employees and others. Provide monitoring and health surveillance in appropriate cases. Plan for emergencies. Provide appropriate PPE and control measures as required, to lower the risk to an acceptable level. Monitor and check that all controls are in place. Train all employees on cement manufacturers recommendations for product use. Provide regular health checks by the company doctor. Provide an evacuation plan in case of spills. Employee duties The COSHH Regulations contain three duties that an employee must follow when handling substances that may cause harm. Table 17.4 lists these duties, along with suggestions on how you can comply with them. Table 17.4 Employee duties under the COSHH Regulations Duty Attend relevant training provided by the employer. Report hazards and risks. Use control measures. Compliance Attend training and achieve certification on the use of admixtures. Tell your supervisors about hazards and risks associated with bricklaying. Use PPE provided for personal protection. Did you know? Architects and designers have a legal duty under the CDM Regulations to make sure that their design is safe and that it can be safely constructed. Construction (Design and Management) Regulations 2007 (CDM) These Regulations were introduced to help reduce the accidents and injuries that happen during the design and construction of buildings. Contractor duties Under these Regulations the employers is called a contractor. This is because it is contractors that undertake the work on site. Table 17.5 lists their duties and examples of ways to meet these. 8 BTEC First Construction and the Built Environment

10 Brickwork and Blockwork Operations UNIT 17 Table 17.5 A contractor s duties under the CDM Regulations Duty Plan, manage and monitor own work and that of others. Check competence of all employees. Train employees and provide information. Make sure employees have adequate welfare facilities. Cooperate and coordinate work to ensure the health and safety of all. Compliance Produce a method statement covering the construction of the cavity walls and internal blockwalls. Check all qualifications of bricklayers. Audit training records and plan training for all bricklayers and labourers. Provide the required site facilities (for example, toilets and a canteen). Attend regular safety meetings with the workforce. Activity 17.1 The CDM Regulations cover a wide range of duties for other people involved in the design and construction of a building. Go to the Health and Safety Executive s website. Find out what these other duties are and to whom they apply. Employee duties An employee has certain duties under these regulations. These are listed in Table Table 17.6 An employee s duties under the CDM Regulations Duty Make sure you only carry out work that you are competent to do. Report hazards and risks. Cooperate with others and coordinate work to ensure your own health and safety and that of others who may be affected by the work. Follow site health and safety rules and procedures. Compliance Do not undertake any work outside of the bricklaying responsibilities, unless you are trained to do so. Advise the foreperson or site manager of any risks when constructing walls. Take part in the toolbox talks with the team. Obey the site rules to set an example as a competent bricklayer. 9

11 TOPIC A.1 Activity 17.2 Bricklayers are working on the first floor cavity wall of a domestic house. This involves working at height. Explain the health and safety requirements that the bricklayers have to fulfil when they are doing this task. The Work at Height Regulations 2005 Employer duties Table 17.7 lists the duties of an employer on a construction site and gives an example of how each duty can be met. Table 17.7 Employer duties under the Work at Height Regulations Duty Avoid work at height where possible. Make sure all work at height is properly planned and organised. Make sure all work at height takes account of weather conditions that could endanger health and safety. Provide work equipment or other measures to prevent falls when working at height cannot be avoided. Make sure those involved in work at height are trained and competent. Make sure the place where work at height is done is safe. Make sure equipment for work at height is appropriately inspected. Make sure the risks from fragile surfaces are properly controlled. Make sure the risks from falling objects are properly controlled. Compliance Do not work at height unless there is no other option. Organise suitable access to the workplace that is safe for brickwork operations. Do not lay bricks while working on scaffolding that is wet, slippery or covered in snow. Check the scaffolding before accessing it. Make sure that it has been inspected, and report any defects. Provide training on working at height for all bricklayers and labourers. Make sure guard rails are in place, and that bricks and blocks are not stacked too high. Check the scaffold inspection tag before accessing it to undertake brickwork operations. Do not climb off the brickwork scaffold onto the roof or unsupported floors. Make sure that bricks are not stacked above the brick guard mesh and handrails, and that there are no gaps in the guarding. Case study Key term Prohibition Notice a notice that is served by the Health and Safety Executive (HSE) to the contractor. It stops all work on site until the dangerous occurrence has been corrected. A bricklayer who ignored warnings to stop working on a hazardous scaffolding tower was taken to court by the Health and Safety Executive. The scaffolding had been erected on a busy street and had not been fitted with handrails or toe boards. The bricklayer had been issued with a Prohibition Notice. He had not obeyed it and so was taken to court. 1 Who might have been harmed as a result of the bricklayer s actions? 2 What could have been the consequences if he had carried on working? 10 BTEC First Construction and the Built Environment

12 Brickwork and Blockwork Operations UNIT 17 Employee duties These Regulations are very important for employees, as they are the people on a construction site who are most likely to work at height. Table 17.8 lists the duties under the Regulations and how a bricklayer can make sure that they comply with these. Table 17.8 Employee duties under the Work at Height Regulations Duty Report any safety hazards to your employer. Stop working if you think it is unsafe. Follow any training or instruction. Use any equipment properly, following any safety instruction, including safety devices, provided by the employer. Compliance Inform the brickwork supervisor if you find any hazards. Stop work and get off any scaffolding if it seems dangerous or unsafe. Attend working at height safety training. Use the ladders or stair access, platform lifts and scaffolding correctly. Manual Handling Operations Regulations 1992 Risk assessment Can manual handling be avoided? Things to consider before manual handling Can the load be moved by mechanical means? Can the size or weight of the load be reduced? Figure 17.1 The employer s duties under the Manual Handling Operations Regulations Employer duties Figure 17.1 illustrates the employer s duties under these Regulations. They are: to assess the risks involved in manual handling that cannot be avoided, and reduce the risk to avoid the requirement for manual handling or limiting loads where possible to provide mechanical means of handling where possible to reduce the risk of injury as much as is reasonably possible. 11

13 TOPIC A.1 Employee duties It is the employee who lifts the weight, so they must assess the load to be lifted. For example, blocks that have been left out uncovered in the rain will absorb water and become heavier. As an employee, the duties that you will have are: to cooperate with your employer on manual handling to make proper use of equipment provided for your safety during manual handling not to misuse or damage anything provided for manual handling to inform your employer if you spot hazardous handling activities to make sure that your activities do not put others at risk. Do you think this is the correct way to move a bag of cement? Just checking 1 What are your duties under the CDM Regulations? 2 What precautions should you take with manual handling? 3 What are your employer s duties under the Health and Safety at Work etc. Act 1974? Assessment activity 17.1 English You have been asked to build a gable wall. The site manager has provided two tower scaffolds with boards across. You do not feel safe using such a method to work from, and have complained. The site manager has stated that it is perfectly safe and in accordance with Regulations. You challenge this and decide to write out all the important parts of the Regulations that the site manager is breaking. Produce this document for the site manager. Tips Remember to include the requirements from two of the Regulations covered in this unit. Research a summary of each Regulation that you are going to include. To improve your response, your description should be in the form of a thorough explanation of the two Acts. You should apply your explanation to a brickwork or blockwork situation. When you are asked to justify, remember to make sure you explain why a specific Regulation is in place, and give reasons for its use. 12 BTEC First Construction and the Built Environment

14 Brickwork and Blockwork Operations UNIT 17 Learning aim B TOPICS B.1 B.2 Constructing brickwork walls Introduction In this topic, you will develop your manual skills in the production of a solid one-brick wall. These kinds of walls are used for property boundaries or garden walls. They consist of different bonds from those that you have previously encountered in cavity wall construction. The different bonds are used to produce very pleasing facing brickwork. This can add value to a property. Materials used to construct brickwork walls Facing bricks There are a number of different facing bricks you can use to give an attractive finish, or to make a modern building fit in with a conservation area. The following are typical bricks that you can use to produce good-quality facework. To reduce their weight, they may be perforated with circular holes. Machine-made facing bricks are mass produced, pressed clay bricks or wire cut to produce a different face on the side and end. These are an economical brick to produce. They are available in many different colours and textures. Hand-made facing bricks are expensive because of the amount of labour needed for their production. They are hand pressed into a mould, then levelled and burnt. Handmade bricks have a unique character that allows them to blend into a conservation area so that they match the surrounding built environment and blend in. Discussion You will need to use mathematics to construct a onebrick wall to the specification you have been given. What application of mathematics will you use? What calculations will you have to do before starting the task? Link For more on mathematics in construction, see Unit 3: Scientific and Mathematical Applications for Construction. Key terms Facework the brick face and its finish that you can see. Compressive strength the amount of strength in the material to resist crushing. Water absorption the amount of water a material can soak up through the pores or air pockets in its structure. Engineering bricks are hard, dense, heavy bricks that are used in very wet areas. They have two classifications: Class A are the better-quality bricks, with a higher compressive strength and water absorption figure. They tend to be more uniform in colour. Class B are cheaper than Class A, and are more commonly used in manholes and work below ground. Engineering bricks can be perforated with holes. This reduces the weight of the brick, but still maintains its strength and moisture resistance. Common bricks These bricks are cheap and readily available. They are often used where they cannot be seen in places where a cut brick is needed for example, under supporting lintels. Common bricks contain a frog within them. This is a recess that is formed on one bed face, and that reduces the weight of the brick. 13

15 TOPICS B.1 B.2 Concrete common bricks are, as you can tell from their name, bricks made from concrete. They are ideal for use as a course of bricks to make up levels on blockwork. They are strong and can be covered with plaster finishes. Concrete bricks tend to be solid bricks. Reject facing bricks are often used as common bricks. This is an economical use of a brick that would not usually be used for facing work. Common bricks Special bricks As their name suggests, these are special bricks that are made for different applications. They are often different shapes and used for different applications. They include: copings and cappings used on the top course of a wall to encourage water to run off the top of the wall and protect the rest of the brickwork below from excessive wetting and freezing, which can cause damage bullnose bricks these have rounded corners to form a bullnose feature to the top of a wall and remove the sharp corner angle and cant bricks instead of a bullnose, these bricks have an angle cut across the end, which adds a different design feature to a wall and allows angled changes of directions to be achieved in a wall length plinth bricks are used to form a plinth at the base of a wall. They allow the base to be thicker than the top section of the wall, and make a decorative feature. Surface finish Key terms Extruded pressed from a mould as a continuous strip; this is then cut into individual bricks. Abraded a finish formed by a mechanical process that roughens the surface finish. This is the texture on the face of the brick that can be formed using a variety of different processes. Texture adds variations into walls, which adds to the unique design of a building. These textures may be: smooth this is a hydraulic pressed brick that produces a smooth face dragwire a wire drags through the clay as it is extruded sand faced sand is applied to the face before firing, to give a decorative finish rustic a decorative face is pressed into the brick to give it a rustic, textured look tooled this is an abraded finish on a brick, but is more associated with stone work. 14 BTEC First Construction and the Built Environment

16 Brickwork and Blockwork Operations UNIT 17 Mortars Mortar bonds the bricks together to form a strong wall. It is made using four products: sand, cement, admixtures and water. Some of the different types of mortars that are used in bricklaying are: cement mortars these are covered in Unit 7: Exploring Brickwork and Blockwork Principles and Techniques sand lime mortars modern-day admixtures are replaced by lime. Lime acts as a coating to the sand and its grains can roll over each other, which makes bricklaying an easier task. coloured mortars modern technology allows coloured pigments to be added to the sand and used to form different-coloured mortar joints, in a decorative fashion ready-mixed retarded mortars these are produced in tubs and delivered to the site. They reduce any wastage, as no mixing occurs on site and all of the product can be used, as it does not set hard straight away. Did you know? Lime was used 4,000 years ago to form a plaster used in the construction of the Egyptian pyramids. Construction of solid walls in brickwork Brick sizes Bricks are made in a standard size in the UK. Figure 17.2 shows the metric sizes of a brick. All bricks in a pack should be within these dimensions. They should be rejected if bent or distorted or cracked. Frog mm Header face 65 mm 215 mm Stretcher face Arris Figure 17.2 Standard brick dimensions To calculate the number of bricks in one square metre of wall, you need to multiply the area measured by 60 bricks to give the total quantity of bricks that you will need to build a cavity wall leaf in stretcher bond. When one-brick walls are to be constructed, this is doubled to 120 bricks, as the wall is twice the thickness. 15

17 TOPICS B.1 B.2 Calculation of quantities To help you learn how to calculate quantities, Table 17.9 gives some examples. These will help to show you how to use the standard brick dimensions and the 10 mm for the mortar joint. Table 17.9 Examples of calculating quantities Length A wall is 2363 mm long. Brick length = 215 mm + 10 mm joint = 225 mm = 10.5 bricks in length A half-brick cut will be required within the wall. Height A wall is 2100 mm high. Brick height = 65 mm + 10 mm joint = 75 mm mm = 28 courses of brick height Quantity Multiplying the number of bricks in length by the number of courses will give the number of bricks to order: = 294 bricks Wastage When you have to cut a brick, it might not cut cleanly, so the other half may not be usable. Often some bricks will be rejected if they are damaged or misshapen. This is called wastage and normally an allowance is added to quantities. This is generally between 2.5% and 5%, depending on the quality of the bricks being used. Quantities of mortar The calculations involved in mortar quantities are complicated and extensive. There are many different methods that you can use to calculate the quantities of mortar, including: discussing it with a mortar supplier and giving them the total number of bricks you are laying looking at standard tables of mortar quantities per type of wall looking at manufacturers data sheets. Setting out the work Key term Course out use the standard heights of a brick plus the joints to establish heights. In Unit 7, you examined the use of corner profiles and gauge rods as pieces of brickwork equipment. Gauge rods are set at 75 mm, which allows you to check that a given height will course out correctly. This will mean that the brickwork will look correct and level. Similarly, corner profiles let you get on with infilling the centre of a wall, without having to build the external corners so you have something to attach a string line to. You can fix a corner profile to three courses of brickwork and stretch a string line between the corner profiles. You can then start the work. 16 BTEC First Construction and the Built Environment

18 Brickwork and Blockwork Operations UNIT 17 Types of brick bonding Stretcher bond is the most common bond used for the construction of houses with cavity walls (see Figure 17.3). It relies on a half lap of the bricks between courses. Along with the setting of the mortar, this gives a strong bond that can carry the building s load and withstand bad weather for example, keeping the rain out. Figure 17.3 Stretcher bond wall Figure 17.4 Flemish bond in a wall Figure 17.5 English bond in a wall Flemish bond is an unusual bond for one-brick walls. It uses a stretcher then a header along each course. If you look at Figure 17.4, you can see that this arrangement alternates on each course, and lines up with the header central to the stretcher above and below. English bond uses a different method, involving a row of headers then a row of stretchers. Figure 17.5 shows this technique for each course of bricks. Both Flemish and English bond are only suitable for one-brick walls, such as garden walls. They make an attractive and decorative feature, and enhance a building s appearance. Types and methods of jointing The flush joint is illustrated in Figure This joint, as its name suggests, finishes flush with the face of the brickwork or blockwork. This is achieved by a wiping action with the brick trowel across the face of the joint, removing any excess mortar. Key terms Stretcher the description of a brick along its length. Header the brick end laid sideways across a wall, with just the end exposed. Flush when the finish is at the same level as the surrounding brick or block faces. The tooled (bucket handle) joint is the most common joint (see Figure 17.7). It is created using a jointing tool. This is run along the joint to create a curved, compressed joint in the shape of a bucket handle. Figure 17.6 Flush joint Figure 17.7 Tooled joint 17

19 TOPICS B.1 B.2 The recessed joint is shown in Figure This joint has a certain depth removed or racked out as the mortar sets. This gives an attractive feature to the brick face. The weathered joint is the most durable. As you can see in Figure 17.9, it encourages the water to run down its slope, out of the joint and away. This gives excellent durability in places that have a lot of driving rain. Figure 17.8 Recessed joint Figure 17.9 Weathered joint Advantages and disadvantages of joints Table shows the advantages and disadvantages of different types of mortar joints that complete the bricklaying process. Table Advantages and disadvantages of joints Type of joint Advantages Disadvantages Flush Tooled/bucket handle Recessed Weathered Gives a uniform feature to the wall A quick and easy weatherproof joint to construct and form A very attractive joint is formed Disperses the water away from the joint Creates a shadow effect to the joint Not easy to keep the face of the brick clean of mortar The joint has not been tooled, so may allow water penetration into the joint Lacks any architectural merit The joint needs to be raked out and recessed using a specialist tool Recessing weakens the joint Difficult to form, and relies on the skills of the bricklayer for consistency 18 BTEC First Construction and the Built Environment

20 Brickwork and Blockwork Operations UNIT 17 Constructing brickwork walls Half-brick walling to corners in stretcher bond is shown in Figure The corner laps each course and the ends may require a cut brick to form the stopped end. Stopped end Figure Stretcher bond corner One-brick walling to corners and attached piers has the overall thickness of one brick across its width. Figures and show the alternate courses in two different types of bond Flemish and English which you can use with one-brick walls. Course 2 Course 2 Course 1 Queen closer Course 1 Figure Corners in English bond and Flemish bond 19

21 TOPICS B.1 B.2 Just checking 1 What are the advantages of using a weathered joint? 2 What does lime do when it is added to a mortar? 3 Give one advantage and one disadvantage of a recessed joint. Course 1 Course 2 Figure Attached piers in English bond and Flemish bond Quality control checks Key term Perpendicular when the vertical is at 90 to the horizontal. Remember Take care to be accurate with your calculations. Do not forget to include the 10 mm for the mortar joints and the calculations for wastage. The more accurate you are at every stage in the construction of your wall, the better the result will be. Once you have finished, carry out a dimensional quality control check upon your work. Get it signed off by a supervisor who can confirm your measurements. The following are typical checks on the quality of the work that you have produced. Face plane deviation this is measured by holding a straight edge onto the face of the work and checking to see how much deviation the constructed wall makes against the straight edge. Level and plumb to appropriate tolerances the horizontal level can be checked using a spirit level, and a plumb line can be used to check verticality. Vertical joints ( perpendicular joints or perps) in line this is a visual observation of the wall. When you stand back from it, the perps should all line up vertically. Selection and blending of bricks this is often undertaken on site to make sure that banding does not happen in the finished wall. This could be a band of slightly different-coloured bricks that have all been taken from one stack. Quality of jointing this relies on the skill of the bricklayer, especially with some of the more complex weathered jointing. The general cleanliness of the completed wall this depends on how careful you are with striking off the excess mortar from the joint, the quality of pointing and whether you clean down the face as you go. A dimensional check to appropriate tolerances this means checking that the length and height of the wall contains the correct number of calculated courses including the 10 mm mortar joint for each course. Assessment activity 17.2 Maths 1 You are going to build a one-brick garden wall in your local area. Choose a jointing technique that you could use and list its advantages and disadvantages. 2 Calculate the resources needed for your wall. It will be 5 m long. Tips Remember to give both the advantages and disadvantages of your chosen joint. Practise the different quality control checks as you build. 20 BTEC First Construction and the Built Environment

22 Brickwork and Blockwork Operations UNIT 17 Learning aims B and C TOPICS B.3 C.3 Safety equipment and safety measures The p ersonal protective equipment (PPE) required for brickwork and blockwork operations was covered in Unit 7 (page 176). The following additional items are included here, as they are often used for brickwork and blockwork operations. Overalls used to keep any mortar or dust away from the skin s surface, as these could act as irritants. Barrier cream applied to the hands and acts as a barrier between any chemical or substance until the hands are cleaned afterwards. Dust mask worn when cutting bricks or blocks with a rotating saw, to prevent inhalation of dust into the lungs. Learning aim C TOPIC C.1 Materials used to construct blockwork walls Introduction In this topic, you will be using a different material a block to produce blockwork walls. These are mainly used as internal partition walls and as inner skins of cavity walls. The blocks are much larger than bricks and are equal in size to six bricks in total. They can therefore be laid a lot faster than traditional brickwork. Blocks and mortar Table lists the different types of blocks used in modern construction. In the right-hand column is a description of the properties of the block and where it is commonly used. Discussion Find out how many different sizes, types and applications there are for blocks. Now discuss the following questions: What blocks can be used below a damp-proof course? What type of block can support load-bearing floors? Table Types and uses of blocks Type of block Trench Solid Description and use These are used within foundations below the damp-proof course, as they are ideal for this highmoisture location. These are heavy, dense blocks used in applications of high loading. Normal strengths are 7 N/mm 2 and 3.5 N/mm 2. continued 21

23 TOPIC C.1 Table continued Type of block Lightweight insulation Keyed Fair-faced Description and use These have an admixture introduced into their manufacturing process that forms tiny bubbles in the block. These trap air and therefore increase the insulation properties of the block, so they retain heat better. They are also called aerated concrete blocks. These have a keyed surface, which means that the face of the block is scored. This allows the plaster finishes to bond more easily to the block face. These have a better-quality face applied to one face or both. This produces a better-looking wall, which does not need to be plastered but which can be painted. The most commonly used size of block has a face size of 440 mm 215 mm. Blocks with this size of face can have widths of: 75 mm 90 mm 100 mm 140 mm 190 mm 215 mm. You will use the same mortars as covered in Topic B.1 (see page 15). TOPIC C.2 Construction of solid walls in blockwork Calculation of quantities To help you learn how to calculate quantities, Table gives some examples that will help to show you how to use the standard block dimensions and the 10 mm for the mortar joint. Table Examples of calculating quantities Length Height Quantity Wastage A wall is 2700 mm long. Block length = 440 mm + 10 mm joint = 450 mm = 6 blocks in length A wall is 1800 mm high. Block height = 215 mm + 10 mm joint = 225 mm mm = 8 courses of block height Multiplying the number of blocks in length by the number of courses will give the number of blocks to order: 6 8 = 48 blocks When a block needs to be cut, this is normally done with a petrol saw, which leaves a clean cut. The wastage factor can be lowered down to 1.5% because damaged blocks can still be used. They will be plastered over to complete wall finishes. 22 BTEC First Construction and the Built Environment

24 Brickwork and Blockwork Operations UNIT 17 Assessment activity 17.3 Set out a corner wall in blockwork, four blocks high and three blocks to one side and six blocks to the other. Build indents into the six-block wall, for a connecting partition wall. Construct a four-block high partition wall into the indents that are left. Tip Try using a blockwork plumb to keep yourself within a tolerance of ±10 mm per metre height and length. Types and methods of bonding Half bond is the only bond used with block walling. Figure demonstrates this bond, which is a half lap of each block against the next course of blocks. Figure Half bond blockwork Indents for junction walls are missing blocks that are left out of every other course. This creates a place to connect another wall into when it is put into place. Toothing is where you leave out connecting blocks so there are gaps between the blocks. This looks like a set of teeth, hence the name toothing (see Figure 17.14). The adjacent wall can then be built into these gaps and connected to the teeth. This creates a strong joint. d Half bond toothing Figure Half bond toothing 23

25 TOPIC C.2 Jointing fair-faced blockwork Blockwork has many uses, from internal walls in sports facilities, where it is painted, to internal walls ready for plastering inside a home. There are only a few jointing types that can be used, due to the nature and size of the blocks (see Table 17.3). Table Types of joint and their advantages and disadvantages Type of joint Advantages Disadvantages Flush Tooled/bucket handle Weathered Quick and easy joint Does not matter if mortar is dragged across the face Quick, easy and a fairly aesthetic (pleasing to look at) joint is formed When using external blocks as a feature, gives a weatherproof joint Not particularly attractive if a paint finish is required Not required if the wall is to be plastered Takes longer to construct, and a high skill level is required Quality control checks You will use the same quality control checks as used in Topic B.2 (page 20). Just checking 1 What are the standard dimensions for a block? 2 What does half lap mean in constructing blockwork? 3 What aspects of a constructed wall would you assess for quality? Assessment activity 17.4 Maths 1 You have been asked to construct a block wall 10 m long and 2.70 m high. Calculate the total number of blocks required. Complete a purchase order to schedule the delivery of these materials to the site. 2 Outline, in a discussion, the advantages and disadvantages of different blockwork resources for the different locations they would be used in. State what typical allowances you would add for wastage. Tips Look at the different blocks (such as trench or lightweight insulation), and outline the advantages and disadvantages of each type. You need to carry out some calculations. Make sure that these are accurate and that you apply the percentage for wastage when cutting. You should try to work within a tolerance of ±10 mm. This is quite a lot of deviation for building your model. To push yourself further, try to achieve a better tolerance than this. Keep checking each course or each block laid for level, gauge and plumb as you build. This will help you to get rid of any errors as you proceed. 24 BTEC First Construction and the Built Environment

26 Brickwork and Blockwork Operations UNIT 17 WorkSpace James Lin Bricklayer I really enjoy building houses. People will spend a lot of their lives in the homes that I helped to build, and that feels pretty special. The length of a house s life does mean that I have to concentrate on producing quality brickwork and blockwork, but seeing the results of all your care and attention tion always make it feel worthwhile. The outside of a house is a potential buyer s first impression of their new home and if the brickwork is attractive, then hopefully that impression will be a good one! When I was learning to lay bricks and blocks, I made sure to check that my work was clean and correct in every dimension. This has become such a habit that I barely have to think about doing it these days it just comes naturally. The other bricklayers and I also check each other s work regularly, just to make sure we re all working to the same standard. Sometimes bricklaying is a tough job, and the weather has an impact on us and on our work. For example, we can t lay bricks when it is too cold, and we have to cover up the day s work to prevent any frost damage in winter. But I love my job, particularly because of the variety of buildings that I get to work on. No two projects are the same, although the bricklaying tasks may be similar, and this means that I m always learning new things. Think about it 1 Do you think bricklaying is a rewarding occupation? 2 Would you be prepared to work in all weathers? 3 How would you ensure quality in your work? 25

27 Glossary A Admixture this is a product that you add to the sand and cement. It makes the mix of materials more workable for the bricklayer to use, so it is easier to spread and level. Abraded a finish formed by a mechanical process that roughens the surface finish. C Compressive strength the amount of strength in the material to resist crushing. Course out use the standard heights of a brick plus the joints to establish heights. E Extruded pressed from a mould as a continuous strip; this is then cut into individual bricks. M Method statement an outline of how you will undertake a construction activity, listing the methods you will use, the labour, plant and materials. P Perpendicular when the vertical is at 90 to the horizontal. Plant construction machinery and equipment that operatives use, for example, a rough terrain fork truck. Prohibition Notice a notice that is served by the Health and Safety Executive (HSE) to the contractor. It stops all work on site until the dangerous occurrence has been corrected. S Stretcher the description of a brick along its length. F Facework the brick face and its finish that you can see. Flush when the finish is at the same level as the surrounding brick or block faces. T Toolbox talk a talk given on a construction site by a competent person about a particular aspect of health and safety. H Header the brick end laid sideways across a wall, with just the end exposed. W Water absorption the amount of water a material can soak up through the pores or air pockets in its structure. 26 BTEC First Construction and the Built Environment

28 Index A access equipment 10, 11 admixtures 7, 8 aerated concrete blocks 22 angle bricks 14 assessment activities 12, 20, 23, 24 criteria 3-4 methods 2, 5 B banding 20 blocks size of 22 types and uses 21-2 wastage 22 blockwork 2 blockwork walls 21-4 bonding 23 calculating quantities 22 half bond blockwork 23 jointing 23-4 quality control checks 20, 24 toothing 23 bricklayers case study 25 team 2 bricks angle bricks 14 bullnose bricks 14 compressive strength 13 dimensions 15 engineering bricks 13 facing bricks 13 header face 15 plinth bricks 14 special 14 stretcher face 15 surface finishes 14 textured finishes 14 types of wastage 16 water absorption 13 brickwork 2 brickwork walls bonding 17 calculating quantities face plane deviation 20 half-brick walling 19 horizontal and vertical checks 20 jointing 17-18, 20 materials one-brick walling quality control checks 20 setting out 16 bullnose bricks 14 C cappings 14 cement: hazards 7 cement mortars 15 chemical hazards 7 common bricks concrete 14 compressive strength (bricks) 13 concrete common bricks 14 Construction (Design and Management) Regulations (2007) 8-9 contractor duties 8-9 employee duties 9 control measures, COSHH 8 copings 14 corner profiles 16 COSHH (Control of Substances Hazardous to Health) Regulations (2002) 7-8 duties under 7-8 risk assessments 8 course out 16 E engineering bricks 13 English bond 17, quarter toothing 23 equipment, safety 7 F facework 13 facing bricks 13 fair-faced blocks 22, 23 Flemish bond 17, flush joint 17, 18, 24 frog 13, 15 27