FLOORS

Question 1

What is the function of a floor?

Answer 1

The function of a floor is to:

Load distribution, provide structural stability, functional support, acoustic/thermal insulation and fire protection.

Question 1

What are the types of floor?

Answer 1

Solid floor, suspended floor, composite floor, raised access floor, floating floors, underfloor heating floor and green access floor.

Question 2

What are the types and properties of a Solid Floor?

Answer 2

Concrete Slab Floors:

Used primarily for ground floors.

Consists of a solid concrete slab placed directly onto a compacted hardcore base, often with a damp-proof membrane (DPM) and insulation.

Can be cast in situ or prefabricated.

Beam and Block Floors:

Made up of precast concrete beams laid across the foundation with concrete blocks infilled between them.

Provides a quick and efficient method for constructing solid ground floors with good thermal and acoustic properties.

Question 3

What are the types and properties of a Suspended Floor?

Answer 3

Timber Suspended Floors:

Traditional method for upper floors in residential buildings.

Consists of timber joists supported by load-bearing walls or beams, with a floorboard or chipboard deck.
Space between joists can be used for services and insulation.

Concrete Suspended Floors:

Often used in commercial and multi-story residential buildings.

Can be constructed using in situ concrete slabs or precast concrete elements like hollow-core slabs.

Offers high load-bearing capacity and fire resistance.

Question 4

What are the types and properties of a Composite Floor?

Answer 4

Steel-Concrete Composite Floors:

Combines steel beams with a concrete slab, creating a composite action that enhances load-bearing capacity and stiffness.

Steel decking is used as formwork and reinforcement for the concrete slab.

Common in high-rise buildings and large commercial structures.

Timber-Concrete Composite Floors:

Combines timber beams or joists with a concrete slab on top, connected by shear connectors.

Provides the aesthetic and sustainability benefits of timber with the strength and durability of concrete.

Question 5

What are the types and properties of a Raised Access Floor?

Answer 5

Used in commercial buildings, particularly offices and data centers.

Consists of a grid of adjustable pedestals supporting removable floor panels, creating a void for cabling, HVAC, and other services.

Allows for flexibility in layout and easy access to building services.

Question 6

What are the types and properties of an Underfloor Heating Floor?

Answer 6

Floors integrated with underfloor heating systems, which can be either hydronic (water-based) or electric.
Typically combined with solid or suspended floor systems.

Provides even heat distribution and energy efficiency.

Question 7

What are the types and properties of a Green Access Floor?

Answer 7

Used in sustainable and eco-friendly building designs.
Roof floors that support vegetation and soil layers, providing environmental benefits such as improved insulation, stormwater management, and biodiversity enhancement.

Requires a waterproof membrane and structural support to handle the additional load.

Question 8

What are the types and the properties of a Floating Floor?

Answer 8

Acoustic Floating Floors:

Designed to reduce sound transmission.
Typically consists of a floating layer of flooring material, such as chipboard or plywood, placed over acoustic insulation or resilient pads.

Common in multi-family housing and buildings requiring high levels of sound insulation.

Thermal Floating Floors:

Designed to improve thermal insulation.
Consists of a floor deck over rigid insulation boards, often used in conjunction with underfloor heating systems.

Question 9

What are the types of materials used in floors?

Answer 9

Concrete, Steel, Timber, Insulation Materials, Acoustic and Thermal Layers, Floor Finishes, Special Materials.

Question 10

What are the types and properties of Concrete in Flooring?

Answer 10

Reinforced Concrete:

Applications: Used in solid floors, suspended floors, and composite floors.

Components: Concrete mix (cement, sand, aggregate, water) with steel reinforcement bars (rebar) to enhance tensile strength.

Properties: High compressive strength, durability, fire resistance.

Precast Concrete:

Applications: Beam and block floors, hollow-core slabs, and other prefabricated elements.

Components: Concrete elements cast in a factory setting and transported to the site.

Properties: Speed of construction, quality control, and reduced on-site labor.

Question 11

What are the types and properties of Steel in Flooring?

Answer 11

Steel Beams and Girders:

Applications: Steel-concrete composite floors, industrial and commercial buildings.

Components: Structural steel sections such as I-beams and H-beams.

Properties: High tensile strength, flexibility, and speed of construction.

Steel Decking:

Applications: Composite floors, used as permanent formwork and reinforcement.

Components: Corrugated steel sheets.

Properties: Lightweight, high strength, and quick installation.

Question 12

What are the types and properties of Timber in Flooring?

Answer 12

Solid Timber Joists:

Applications: Timber suspended floors in residential buildings.

Components: Solid wood joists, often treated for durability and resistance to pests.

Properties: Renewable, easy to work with, and provides good thermal and acoustic properties.

Engineered Wood Products:

Applications: Floors requiring longer spans or higher load capacity.

Components: Laminated veneer lumber (LVL), glulam beams, and I-joists.

Properties: High strength-to-weight ratio, stability, and consistency.

Question 13

What are the types and properties of Insulation Materials in Flooring?

Answer 13

Rigid Foam Insulation:

Applications: Under solid concrete floors and in floating floors.

Components: Expanded polystyrene (EPS), extruded polystyrene (XPS), or polyurethane foam.

Properties: High thermal resistance, lightweight, moisture-resistant.

Mineral Wool:

Applications: Between joists in timber suspended floors for thermal and acoustic insulation.

Components: Fibers made from rock or recycled slag.

Properties: Fire-resistant, excellent sound absorption, and thermal insulation.

Question 14

What are the types and properties of Acoustic/Thermal Insulation in Flooring?

Answer 14

Acoustic Underlays:

Applications: Floors requiring sound insulation, such as in multi-story residential buildings.

Components: Rubber, foam, cork, or composite materials.

Properties: Reduces sound transmission, provides some thermal insulation.

Thermal Underlays:

Applications: Floors with underfloor heating systems.
Components: Reflective foil, foam, or felt.

Properties: Enhances heat distribution and energy efficiency.

Question 15

What are the types and properties of Floor Finishes in Flooring?

Answer 15

Concrete Finishes:

Applications: Exposed concrete floors in commercial and industrial buildings.

Components: Polished concrete, epoxy coatings, or stained concrete.

Properties: Durable, easy to clean, and aesthetically versatile.

Wood Flooring:

Applications: Residential and commercial buildings.
Components: Solid hardwood, engineered wood, or laminate.

Properties: Warm appearance, comfortable underfoot, and variety of styles.

Tile and Stone Flooring:

Applications: High-traffic areas, bathrooms, and kitchens.

Components: Ceramic tiles, porcelain tiles, natural stone (marble, granite).

Properties: Hardwearing, moisture-resistant, and easy to maintain.

Carpet and Vinyl:

Applications: Residential areas, offices, and schools.
Components: Woven or tufted carpet, vinyl sheets, or tiles.

Properties: Comfortable, sound-insulating, and variety of designs.

Question 16

What are the types and properties of Special Materials in Flooring?

Answer 16

Self-Leveling Compounds:

Applications: Creating a smooth, level surface over concrete or timber substrates.

Components: Cement-based or gypsum-based compounds.

Properties: Quick-setting, easy to apply, and provides a smooth finish.

Damp-Proof Membranes (DPM):

Applications: Solid floors to prevent moisture ingress.
Components: Polyethylene sheets or liquid-applied membranes.

Properties: Moisture barrier, enhances durability, and protects interior finishes.

Question 17

What is Dry Rot?

Answer 17

Dry-rot fungus is often thought of as a building cancer, rampaging through buildings and rapidly destroying any timber in path.

Question 18

What is Wet Rot?

Answer 18

Wet rot is basically the timber decaying naturally in the presence of high levels of moisture.

There is almost always a structural defect causing the problem, it may be that the wall adjacent to the timber is suffering from damp, or water collecting on the timber.

Question 19

What is a Waffle Slab?

Answer 19

Used as alternative to an on-site flat slab or a beam and slab suspended floor It requires less concrete, less reinforcement and can be used to reduce the number of beams and columns required with the resultant savings on foundations.

Molds are very strong, lightweight & capable
of supporting all the normal loads encountered in building works.

Question 20

What are the advantages/disadvantages of a waffle slab?

Answer 20

Waffle Slab Advantages:
* Savings on weight and materials (less steel)
* Medium - Long spans >10m
* Attractive soffit appearance if exposed
* Economical when reusable formwork pans used
* Vertical penetrations between ribs are easy.

Disadvantages:
* Depth of slab between the ribs may control the
fire rating
* Requires special or proprietary formwork
* Greater floor-to-floor height
* Large vertical penetrations are more difficult to
handle.
* Needs Skilled labour

Question 21

What is a One Way In-Situ suspended slab?

Answer 21

One-way in-situ solid slabs are the most basic form of slab. Deflection usually governs the design, and steel content is usually increased to reduce service stress and increase span capacity.

Usage: Office buildings – Low rise, Shopping malls, Warehouses

Economic span range: 4-7m

Economic slab thickness range: 150-250mm

Advantages:
Simple construction. Penetrations in the slabs are easily manageable.

Disadvantages:
Associated down-stand beams may require greater storey height.
Deter fast formwork cycles.
Compromise flexibility of partition location and horizontal service distribution.

Question 22

What are the ad/disad of using two way slabs?

Answer 22

Advantage:
Flat ceilings are available in this slab because
there is no beam in the middle of the cell.
The height of the room is more available.
Do not obstruct the reflection of light.
The beauty of the room increases.

Disadvantage:
This slab design method is more complex than
the one-way slab.
Skilled workers are needed.
The construction cost is relatively high.

Question 23

What is the function of floor finishes?

Answer 23

Floors affect room acoustics, contributing to noise or quietness based on materials.

They react differently to light: mirror-like reflections, diffuse reflections, or none.

Dark flooring absorbs light, creating darker rooms; light flooring reflects light, brightening interiors.

Primary wearing surfaces, requiring maintenance and designed for skid resistance, sanitation, and noise reduction.

Question 24

What are underfloor services?

Answer 24

Frequently used for electrical and communication wiring distribution, especially in wide areas with few partitions.

Old methods involve messy rewiring; modern solutions include proper floor boxes, trays, conduits, and trunking.

Alternative systems for flexibility: cellular raceways, poke-through systems, raised access flooring.

Question 25

What are cellular raceways in floors?

Answer 25

Sheet metal ducts for wiring in buildings with in-situ concrete slabs.

Access boxes allow electricians to add or remove wiring easily.

Question 26

What are poke through systems?

Answer 26

Wiring flexibility without raceways; requires working from the floor below.

Question 27

What is raised access flooring?

Answer 27

Ideal for frequent and unpredictable wiring changes.

Easy to adjust for future wiring needs and compatible with various building structures.

Question 28

What is underfloor heating?

Answer 28

Growing alternative to traditional radiators, with wet and dry system options.

Compatible flooring is crucial for effective heating.

Question 29

How is noise reduced through floors?

Answer 29

Impact Noise Reduction:

Multi-storey buildings, especially hotels and apartments, require minimising impact noise transmitted through floors.

Mechanisms for Reduction:

Padded carpeting, cushioned resilient flooring, and resilient underlay reduce impact noise.

Constructing airtight ceilings with heavy materials mounted on resilient clips absorbs sound energy.
Rating Systems:

Floor-ceiling assemblies are tested for Sound Transmission Class (STC) and Impact Insulation Class (IIC) to gauge acoustical performance.

Question 30

What are the traditional hard flooring systems?

Answer 30

Types of Materials:

Concrete, stone, terrazzo, brick, and tile are chosen for their durability and resistance to wear and moisture.

Acoustic Environment:

Hard flooring contributes to a live, noisy acoustic environment but offers aesthetic appeal and durability.

Concrete:

Textures and colors vary, with options for wood float or steel trowel finishes.

Low initial cost and durability but require skilled workmanship.

Stone:

Various building stones used for flooring, with installation involving mortar and grouting.

Coated with clear sealers or waxed for maintenance.

Brick and Brick Pavers:

Installed horizontally or on edge, offering decorative joint patterns.

Pavers preferred for reduced thickness and weight.

Question 31

What materials are used in soft flooring?

Answer 31

Resilient flooring like linoleum, asphalt tiles, and PVC offers durability, variety, and moderate cost.

Vinyl tiles and sheets are popular, easy to install, and come in various colors and patterns.

Carpets offer versatility but require proper installation and maintenance.

Question 32

What is flooring thickness?

Answer 32

Varies from thin resilient flooring to thick brick flooring.

Tapered edgings or thresholds resolve differences in thickness between flooring materials.

Question 33

How does light reflection affect floor finishes?

Answer 33

Various floor materials react differently to light:

Some offer mirror-like reflections.
Some provide diffuse reflections.
Some do not reflect light at all.

Question 34

What is light absorption on floors?

Answer 34

Dark flooring materials absorb most incident light, resulting in darker rooms.

Light flooring materials reflect most incident light, creating brighter interiors.

Question 35

What wears down surfaces in floor finishes?

Answer 35

Floors serve as the primary wearing surfaces of buildings, enduring foot traffic, furniture, water, grit, and dust.

Require regular cleaning and maintenance due to wear and tear.

Question 36

What are underfloor services?

Answer 36

Distribution of Services:

Floors often house electrical and communications wiring, especially in open areas with few partitions.
Conventional Methods:

Traditional methods involve embedding wiring in metal conduits within concrete floor slabs.

While economical, these methods are challenging for rewiring or repairs.

Flexible Solutions:

Commercial buildings demand flexible systems to accommodate wiring changes over time.

Alternative systems include cellular raceways, poke-through systems, and raised access flooring.
Cellular Raceways:

Sheet metal ducts cast into concrete slabs, providing flexibility for wiring modifications.

Access boxes on the surface allow electricians to add or remove wiring as needed.

Poke-through Systems:

Allow wiring flexibility without raceways, but require access from the floor below.

Raised Access Flooring:

Ideal for frequent wiring changes, offering easy access and adaptability.

Can also accommodate ductwork for air distribution, reducing the need for suspended ceilings.

Question 37

What are the primary functions of floors?

Answer 37

Acoustic Impact:

Floors contribute to the acoustic quality of a room, affecting noise levels based on the material used.

Hard floors vs. carpeting: hard floors create a noisy quality, while carpeting contributes to a hushed quality.

Light Reflection:

Various floor materials react differently to light:

Some offer mirror-like reflections.
Some provide diffuse reflections.
Some do not reflect light at all.

Light Absorption:

Dark flooring materials absorb most incident light, resulting in darker rooms.

Light flooring materials reflect most incident light, creating brighter interiors.

Wearing Surfaces:

Floors serve as the primary wearing surfaces of buildings, enduring foot traffic, furniture, water, grit, and dust.

Require regular cleaning and maintenance due to wear and tear.

Design Considerations:

Floors must address factors like skid resistance, sanitation, noise reduction, and electrical conductivity.

Selections should consider combustibility, fire resistance ratings, and structural loads.