Unit 1 (A2 Properties of construction Materials) Flashcards
What are the different types of walls bricks can be used for?
Load Bearing
Non-load bearing
Insulation Wall
Covering wall
What are properties of common bricks
- Cheap
- These are ordinary bricks, which are not designed to provide good finishes appearance or high strength.
- Used for backing courses of solid or cavity walls
What are properties of Facing Bricks
- Give attractive appearance (1) Hence they are free from imperfections such as cracks
- Available in a variety of closures and textures
- Primarily used for external walls of domestic and commercial properties
What are properties of Engineering bricks
- Strong and durable
- Have high compressive strength
- Low water absorption
- They are usually of high density
- Cheap / economical
Used or retaining walls, ground works and in marine environments
Characteristics of Bricks
- Appearance and colour
- Hard
- Durability
- Fire resistance
- Strength
What are the components of concrete
- Cement,
- Fine aggregate crushed stone,
- Add mixtures
- water
wet concrete is also know as green concrete
Benefits of Admixtures
- reduces water requirement in cement
- control the setting behaviour
- Improves workability, durability and strength
Normal Concrete Mix
Fixed cement - aggregate ration which ensures adequate strength
Standard concrete mix
Fixed cement - aggregate ration vary widely
Vary in compressive strength
Design Concrete Mix
Performance of concrete is specified by the designer but the mix proportions are determined by the concrete producer
Cement content can be laid down
Different types of concrete blocks
Solid
Hollow
Cellular
Advantages of using concrete blocks
Less Mortar Less dead weight less time required less cost Thermal acoustic Environmentally friendly
Properties of Aerated Concrete Blocks
- Light in weight (1) making them easy to handle (1)
- Easy to cut and shape (1) reducing the time needed to size blocks (1)
- Accepts nails (1) allowing fixtures to be directly attached (1)
- Good Fire resistance (1) as the material does not burn or give off toxic fumes/fire protection for long period (1)
- High Level of sound insulation (1) reducing noise from other rooms (1)
- Durable material (1) will withstand everyday wear and tear and damage(1)
- Appropriated flat surface (1) which will accept an internal finish (1)
Properties of high density concrete blocks
Durable
High thermal mass
high strength
Insulated concrete blocks
Includes renewable / recycled materials
very good insulating properties
Mortar Mixes
Made from fine aggregate and a binding agent mixed with water.
Cements bricks together to provide stability, whist holding them apart to spread loads evenly
Aesthetically pleasing
Seals gaps to resist wind and rain penetration
Lime is added to improve workability and enables the mortar to cope with thermal and moisture movement
Hydration
What are the requirements of Mortar
Long life requirements
Adequate compressive strength
Durability to resist the elements
joint sealant
Workability
What are he 3 main types of sand ?
Builders Sand: pure, clean sand. Has had all impurities washed out. (Mainly used for mortar mixes)
Sharpe Sand: Used in the production of concrete works
Silver Sand: Used for brushing into joints on block paving
What are the requirements of plaster board
Fire Resistance
Sound Absorbent
Water Resistance
Impact Resistance
Glass
Glass Plays an essential role in the facade (external face of a building)
Transparency
Glass is commonly used in modern architecture to open up a building
What is the purpose of insulation?
To retard/ stop the flow of heat, electricity and sound
What is the purpose of a thermal insulator
To act as a partial or total barrier in the passage of heat
What properties should a thermal insulator posses
- Low thermal conductivity
- A high thermal resistance point
- Stale to thermal shock (i.e should not break on repeated heating and cooling)
- Moisture Resistant
- Able to withstand vibration and have good strength
Fiberglass
- Common insulation used in modern times
- Made by weaving fine strands of glass into an insulation material
- Minimises heat transfer
- Non-flammable insulation material
Drawback
1. Dangerous to handle as it can cause damaged to the eyes, lungs and eyes if the correct PPE isn’t worn
What are the properties of Cellulose insulation
- Eco-friendly. Made from recycled cardboard, paper ect
- Minimises fire damage as contains next to no oxygen within it
- One of the most fire resistant forms of insulation
- Cost effective and cheaper than fiberglass
Mineral Wool
- Used in fiberglass, rock wool and slag wool
- Not fire resistant. However, it is not combustible
- when used in conjunction with more fire resistant forms of insulation, mineral wool can be an effective way of insulating large areas
Polyurethane Foams. Expanded and Extruded
- Can be sprayed into areas that have no insulation
- Fire Resistant
- Good sound and thermal insulation material
- Highly flammable and needs to be coated in a fireproofing chemical
What the three types of roof
Flat roof - used where rainfall is low and climate is moderate
Pitched/sloping roof - used where rainfall is low
Curved roof - used to cover large column free areas e.g factories
Slate roof tiles
Advantages
1. Long life span
Disadvantages
1. Heavy and requires a strong roof
Clay roof tiles
Advantages
- Low maintenance
- Fire, mould and insect resistant
Disadvantages
1. Fragile and expensive
Concrete roof
A solid slab of concrete capping the top of the house. Concrete roof protects building against storm winds
Felt
First layer is nailed to the roof deck and other layers glued in place with bitumen adhesive
The final layer often has chippings on and is thicker higher grade
Advantages of steel
- Recyclable
- Cost effective
- High strength
- Will not rot, split, crack of creep
Disadvantages of steel
- Losses strength at high temperatures
- Prone to corrosion in humid or marine environments
- must be painted periodically
What is a property of stainless steel
Prevents corrosion
Polyethylene Damp Proof Course
- It is designed to prevent the passage of moisture in brick and block work from external sources.
- Cost Effective
- Durable
- Improves Mortar adhesion
Used in cavity walls
Damp Proof Membranes
- Used Below solid concrete floors
- prevents dampness from occurring
- Can withstand rough handling and has a high puncture resistance
UPVC (Unplasticized Polyvinyl Chloride)
- Conventional material used for window frames, soffits, guttering, fascia, bargeboards ect
- Easy to mould into different shapes
- Good thermal performance
- Low maintenance
- Cost effective
- Available in many different colours and finishes
Timber
- Standing Timber - Part of a living tree
- Rough Timber - When it has been felt
- Converted timber - Sawn to various markets. e.g joists and floor boards
Soft Wood
- Timber from tress that do not loose their leaves
- Grow much quicker than hardwood
- Cheap
- More available
- Used for houses, furniture and fencing
Hardwood
- Timber that comes from trees that loose there leaves in winter
- Used for strong framed construction, flooring and expensive furniture
Examples of softwood
- Pine Wood
- Redwood
- Larch
- Cedar
Examples of Hardwood
- Oak
- Ash
- Walnut
- Maple
- Beech
Ply Wood
- Widely available
- Finishes can vary
- Made by bonding veneers of soft / hard wood or both
Chipboard
Comes in different densities.
Normal density - soft and flaky
High density - solid and hard
MDF
- Dense
- Flat
- Stiff
- Free from knots
- Easily manufactured
- No voids and better edges then ply or chipboards
Particle board
- Age usually no more than 5 years
- very sensitive to water an even moisture
- Light weight
- Eco friendly - made from wood waste
What are properties of obscured glass
- Allows light to pass through (1) while providing a level of privacy for individual rooms
- Provides decorative effects (1) because it is available in a wide range of styles (1)
- Can have ‘one way’ properties allowing people to look out but not into rooms
What are the properties of float glass
- Float glass is transparent (1) allows goods to be easily viewed (1)
- Float glass is very flat (1) so does not distort the view through the window
- Large panes of glass are possible (1) allowing for single windows to span full shop width
- Can be formed into curved shapes (1) meaning there is more flexibility with shop front designs (1)
What are properties of toughened glass
- Fragments of toughened glass have no cutting edges
- Can accommodate high tensile force
- Toughened glass withstands a dead load more than four times that of ordinary glass.
What are properties of smart glass
- can be used for windows, shelves large size doors and table tops
- Window glass that can tint on demand
What are properties of laminated glass
- Holds together when shattered which is done by interlaying sheets of glass
What are properties of patterned glass
- Has patterns or textures impressed on one or both sides in the process of rolling