What are suspended timber floors?
Suspended timber floors are not the same as floating floors or raised floors . This is a method of floor construction in which timber joists are supported by load bearing walls or foundations and typically covered with floorboards on the top. This creates a gap to accommodate ventilation and reduce the chance of damp accumulation.
What is the difference between solid and suspended flooring?
Floor structures are generally one of two types – solid or suspended. Suspended timber floors, which are typically found in older houses, are normally made from timber floorboards which are then attached to joists just above the foundations of a house.
What is a timber floor in construction?
Construction Studies Q1. Suspended Timber Ground Floors consist of the finished timber floorboards being attached to floor joists, which are suspended above the subfloor of the foundation. These floor joists are raised above the subfloor on small supporting walls called tassel walls (or sleeper walls).
What are the benefits of a suspended floor?
The big benefit for choosing a suspended floor (whether concrete or timber) is that the construction is simple. The materials can be more expensive than other flooring options, but there is very little needed in the way of ground preparation which makes the overall cost lower on the whole, particularly for the labour involved.
What is a suspended floor?
A suspended floor means you have a crawl space underneath your ground floor. Suspended timber floors are usually found in older houses, and are normally made from timber floorboards, which are attached to the joists just above the foundations of a house.
What is a concrete suspended floor?
A suspended concrete floor is a floor slab where its perimeter is, or at least two of its opposite edges are, supported on walls, beams or columns that carry its self weight and imposed loading. The floor spans between supports and will normally deflect under load to a dimension that is limited by the design used.
How do you make a suspended timber ground floor?
0:372:15Ground Floors - YouTubeYouTubeStart of suggested clipEnd of suggested clipThese could be built from brick or stone. And was sometimes honeycombed to help ventilation of theMoreThese could be built from brick or stone. And was sometimes honeycombed to help ventilation of the floor. Void. A strip of timber known as a wallplate provided a level surface.
How do you strengthen a suspended floor?
Fix bouncy floors by adding bridging, adding a layer of plywood or adding a wall or beam. We'll show you three ways to stiffen up your bouncy floor—by adding bridging, installing plywood along the joists and adding a wall or beam under the floor. Any one of the three can solve your problem, depending on your situation.
What is the difference between suspended and non suspended slab?
Suspended slabs are slabs that are not in direct contact with the ground. They form roofs or floors above ground level. Suspended slabs are grouped into two types: one way slabs which are supported on two sides.
How thick should a suspended concrete floor be?
The minimum thickness for concrete slabs should be 50 mm. Anything less than this will be a disaster.
Why do some houses have suspended floors?
Unlike standard ground floor construction, suspended floors are not sitting directly on the ground. This allows air flow and ventilation to prevent the mould and dry rot that would otherwise occur over damp ground. However this air flow can leave the problem of draughts and cold in the house if not insulated correctly.
What are three materials that may be used to support suspended floor framing?
This may be tongue-and-groove particle flooring board, fibre-cement sheet, load-bearing wood or bamboo floorboards (some thin boards are meant to be supported by other materials underneath) or even more unusual materials such as reinforced AAC (autoclaved aerated concrete), such as Hebel PowerFloor.
How do you insulate a suspended floor from below?
Insulating Suspended Floors by Working Underneath the Boards It is advisable that a batten be fixed to the side of the floor joist, flush with its underside, to support the insulation. Push the insulation in between the joists, again ensuring a snug fit.
Why does my floor shake when someone walks by?
Floor vibrations are generally related to human activity, vibrating machinery and external forces. Walking is the most common source of floor vibrations and more than anything is simply considered a nuisance.
How much heat is lost through a suspended floor?
While the two flooring types are very different, the general estimated heat loss for all flooring is around 10%. This figure is a lot lower than the loft or walls, but still plays a key role in the amount of heat that a property is losing.
Can sagging floors collapse?
Sagging floors are not only deformed and unappealing but they can be dangerous. They can collapse and cause injuries if they're not fixed quickly.
How thick is a suspended concrete slab?
Suspended Slab In a residential situation, the slab is around 200mm thick and is supported by external sub-floor walls of brick or concrete block etc. The slab is also supported by free-standing brick or concrete piers.
When were suspended concrete floors first used?
Early Timber Floors Most houses at the end of the Victorian period (1900) were built with suspended ground floors.
What is concrete floor?
A concrete floor is typically one in which a flat slab is formed of concrete, which is either poured in-situ or precast in a factory. Rebar, also known as reinforcement steel and reinforcing steel, is a steel bar or mesh of steel wires often used to reinforce concrete.
What are the classifications of concrete floor systems?
Four types of concrete floor systems are used in ICF home construction: concrete on steel joists, concrete on steel deck, concrete slab and joist, and precast concrete.
What is a suspended floor?
Floor structures are generally one of two types – solid or suspended. Suspended timber floors, which are typically found in older houses, are normally made from timber floorboards which are then attached to joists just above the foundations of a house.
What are the drawbacks of suspended timber floors?
Q: What are the drawbacks to suspended timber floors? They can tend to deteriorate more quickly as the timber can rot, so they need a little more maintenance than other flooring types. They can also feel a bit draughty which is why they need to be properly insulated.
Can you run wires under a timber floor?
It’s easier to run wires under the floorboards of a suspended timber floor, and because it doesn’t touch the ground, it will absorb less moisture from the earth so it limits structural damage from damp which is a benefit if your home is in an area with poor drainage.
What is suspended timber floor?
Suspended timber floors are sometimes referred to as hollow timber floors. Suspended timber floors are not the same as floating floors or raised floors . This is a method of floor construction in which timber joists are supported by load bearing walls or foundations and typically covered with floorboards on the top.
What are the issues with suspended wood floors?
In addition to damp, there are two common issues associated with suspended timber floors: drafts and noise .
How to prevent moisture from accumulating in the gap between the floor and the surface below?
To prevent moisture from accumulating in the gap between the floor and the surface below, ventilation is essential. This can be accomplished by fitting airbricks in external walls .
When was the level ground floor used?
This type of construction was commonly used during the Victorian era. It is still found in older buildings and is sometimes used to create a level ground floor when ground surfaces are uneven.
Why do suspended timber floors need to be ventilated?
Suspended timber floors need to have spaces underneath ventilated via air 'bricks' through the outer walls and gaps in any internal walls so that the air can move across the building underneath the floors to prevent the build up of moisture in the timber which could lead to fungal attack.
What is the insulation value for suspended floor?
Any timber suspended floor should have insulation between the joists, in England and Wales the 2014 requirement was a U value of 0.11W/m 2 K for new build, 0.25W/m 2 K for refurbishments.
How big is the space between a concrete base and a floor?
However, where the space between the concrete base and the floor is greater than 45cm, Fig 3 shows an alternative arrangement where the joists are supported in the inner wall, the size of joists is dependant on the span of the floor and there will be a limit on the span that can be accommodated but this is unlikely to cause an issue in a domestic property.
Do air bricks have to be under the floor?
In old properties (1910 to 1980 ish), air bricks were often fitted just in the outer brick skin with a brick left out in the inner skin, thus the air brick vented both under the floor and the wall cavity, but modern regulations require the air brick to bridge the cavity and just ventilate under the floor.
What is suspended timber floor?
A suspended timber floor is usually constructed using timber joists suspended from bearing walls, which are then covered with either floorboards or some other for of boarding material. The joists are typically laid across the shortest span .
What is floor in construction?
According to Approved Document C, a floor is the 'lower horizontal surface of any space in a building, including finishes that are laid as part of the permanent construction .'
What is floating floor?
A floating floor is a floor that is not fixed to the layer beneath it. Floating floors are particularly common in refurbishment works, and can be used to help improve the thermal or acoustic insulation of a floor construction . See: Floating floor for more information .
Which has greater span and load potential per unit weight?
Ribbed floors have greater span and load potential per unit weight than flat slab construction .
What is a raised floor?
A raised floor (sometimes referred to as an access floor or raised access floor) is a floor created above a solid floor slab, leaving an open void between the two. This void can be used to distribute building services. Raised floors are often found in offices, or in spaces that have a high demand for information and communications infrastructure such as data centres .
Why do we use sprung floors?
Sprung floors are used for activities such as dance, indoor sports, and multi-purpose halls where specific properties of shock absorption and energy return are desirable to reduce the occurrence of injuries that may result from repeated impact or falls. They can also help maximise performance .
How to vent a void between the floor and the ceiling?
Ventilation may be provided to the void between the floor and the ceiling below by placing air vents / air bricks within the exterior walls, allowing air to travel from one side of the building to the other. This can, however, cause a problem of draughts, which can be avoided by installing an airtight breather membrane which will help maintain an airtight seal.
Why choose suspended floor?
The big benefit for choosing a suspended floor (whether concrete or timber) is that the construction is simple. The materials can be more expensive than other flooring options, but there is very little needed in the way of ground preparation which makes the overall cost lower on the whole, particularly for the labour involved.
How to construct a suspended timber floor?
There are three key things that need to be considered when constructing or renovating a timber floor: The span: It is possible to create a suspended floor of any size using sleeper walls to bridge the span. The span that can be achieved is determined by the size of the timber joist used.
What is the span between a sleeper wall?
Sleeper walls are built on small foundations and hold up the joists at regular intervals; the distance between them is referred to as the span. The width of these spans depends on the size of the timber used for the floor joists and more can be seen about joist spans in our loadbearing walls project.
What is a hollow floor?
Hollow floors, also known as suspended or timber floors, are simply timber joists suspended across and supported by load bearing walls under the floor. The ends of these timber joists are built into, or suspended by joist hangers from the external walls of the property.
Why is ventilation necessary on hollow timber floors?
Ventilation: Ventilation beneath a hollow timber floor is really important as if any moisture that collects cannot be ventilated away can cause rot. Airbricks need to be fitted on external walls and ventilation through the sleeper walls is required, whether using airbricks or half brick gaps in the wall construction.
What is a sleeper wall?
Sleeper Walls for Suspended Timber Floors. The purpose of the sleeper wall is to allow the use of smaller (thinner) timbers for the joists and to ensure that the joists for the suspended floor can span the required distance without the risk of failure.
What is a load bearing wall?
The internal load bearing walls are called sleeper walls and are very often built with gaps in between the bricks to allow a free flow of air under the floor. This stops any build up of condensation and is assisted by building in airbricks through the external walls.
What is a beam and block floor?
The beam and block floor system is a popular form of domestic floor construction. It is an economical option due to off site manufacture of the beams and blocks, fast assembly and little requirement for specialist labour or equipment. The installation of a beam and block floor is not usually weather dependent and therefore specifying this form of construction can reduce site delays that other methods might encounter. Beam and block flooring demonstrates good noise reduction and fire resisting properties, and is also suitable to host underfloor heating systems.
What are the two types of concrete floors?
There are two types of concrete floor system commonly used in residential construction; ground bearing and suspended. In this article we will be focusing on the suspended concrete floor, particularly beam and block floors. The suspended floor does not rely on support from the ground below but instead is supported by the external walls, ...
What is grout insulation?
The grout also keeps insects and vermin out and assists with air tightness. Insulation is usually positioned on top of the beam and block floor, a concrete topping or screed is then laid onto the insulation. An upstand perimeter insulation is installed around the edge of the concrete topping or screed in order to prevent thermal bridging.
What is infill block?
Infill blocks are then positioned between the T-beams, these blocks are usually lightweight concrete. A sand cement grout is often brushed over the surface, filling any gaps providing a good load distribution and avoiding movement in the blocks. The grout also keeps insects and vermin out and assists with air tightness.
What is EPS block?
Expanded polystyrene (EPS) blocks are also used as infill between the beams. Not only do these blocks provide excellent thermal performance, they increase construction times as they are lightweight and easy to work with. The blocks are either designed to lap under the concrete T-beam in order to prevent cold bridging, or an additional insulation layer is positioned over the EPS infill blocks. More manufacturers are developing EPS block systems which have varying profiles and methods of construction. They are fast, efficient and would be likely to over take the concrete blocks in popularity over the years due to their enhanced benefits.
Can suspended concrete be cast?
Suspended concrete floors can be constructed using different methods. They can be cast in situ reinforced concrete slabs, precast concrete planks or slabs, or the focus of this article, beam and block floors.
Does a suspended floor have to be supported by the ground?
The suspended floor does not rely on support from the ground below but instead is supported by the external walls, and therefore the foundations below.
