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MB Concrete Masonry Housing May09

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    Concrete and Masonry Housing

    AN OVERVIEW OF METHODS AND BENEFITS

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    Contents

    The benefits ofheavyweight construction 3

    Energy-efficient housing 5

    Heavyweight housing solutions 8

    Summary 11

    2 Concrete andMasonry Housing

    Introduction

    The UK shortage of housing underlines the need for fast and

    efficient construction. However, this speed must not be at the

    expense of quality and long-term performance. The new homes

    to be built must not only be structurally robust and affordable,

    they also need to provide comfortable living space that has the

    flexibility to adapt to future needs. A further priority will be toensure that these homes work with rather than against the

    environment and in so doing they should negate the need for air

    conditioning and reduce the need for heating, thereby helping to

    reduce energy consumption and fuel bills.

    The concrete industry can offer a range of construction methods

    from foundation methods to roof tiles, that are innovative and

    fast whilst offering the high performance and inherent benefits

    of heavyweight construction. These construction solutions offer

    the efficient delivery of long-term performance and best value

    and meet the highest level of the Code for Sustainable Homes.

    This is a combination that is welcomed by both social housing

    providers and their tenants, and by the private sector. Of course

    refurbishment and maintenance products are also available,

    however, these are outside of the scope of this guide.

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    3Concrete andMasonry Housing

    The benefits ofheavyweight constructionConcrete and masonry construction offers a wide range of performance benefits that are inherent to the

    materials and are, consequently, available free of charge.

    Long-term sustainability

    The environmental impact of heating, cooling and lighting our homes

    is considerable. It accounts for some 27 per cent of total UK CO2

    emissions. These operational emissions far outweigh the embodied

    CO2

    of the construction materials which are used to build our homes.

    Using the inherent thermal mass of heavyweight construction together

    with passive solar design features such as window size, orientation

    and shading can provide a real, long-term sustainable solution by

    significantly reducing the heating and cooling energy demands of a

    home over its lifetime. Indeed, using concretes thermal mass can reduce

    the energy consumption of buildings.

    Of the nine design categories in the Code for Sustainable Homes, energy

    and CO2

    accounts for 36 of the 100 available points. This reflects the

    importance placed on minimising operational CO2

    emissions relative

    to the other impacts included in the Code. Concrete and masonry

    construction solutions are fully able to meet the requirements of the

    Code for Sustainable Homes, including those for the highest code level

    5/6 (for more information downloadAchieving Code Level 5 with Concrete

    and Masonryfrom www.concretecentre.com/publications ).

    Locally sourced

    The UK can be self-sufficient in concrete. Unlike, timber and steel, the UK

    is able to produce almost all the concrete it needs domestically. This self-

    sufficiency enhances concretes sustainability by allowing it to be locally

    sourced rather than reliant on imports.

    Some 90 per cent of timber used for construction is imported, often

    from as far away as Canada. Structural steel relies on the importation

    of raw material notably from Brazil. This has serious environmental

    consequences. The aggregates for concrete are from UK quarries and UK

    manufactured reinforcement is made from 100 per cent recycled UK scrap

    metal. In addition, in the UK the average delivery distance from a ready-

    mixed concrete supplier is six miles and reinforcement fabricators are

    located throughout the UK making it easy to locally source all materials.

    Responsibly sourced

    Both ready-mixed and precast concrete can easily be sourced from

    suppliers operating in accordance with an environmental management

    scheme (typically ISO 14001) and their products will score points for

    responsible sourcing in the Code for Sustainable Homes. In additionto this, further points can now be sourced in BREEAM if the supplier

    is accredited under the new BES 6001 standard for the responsible

    sourcing of construction products.

    Built-in sound insulation

    Up to 4.7 million people suffer as a result of noise from traffic, industry

    or noisy neighbours according to statistics from the 1996 English House

    Condition Survey. The mass, which is inherent in heavyweight materials

    such as concrete and masonry, provides improved sound insulation

    compared with lightweight construction techniques - without the need

    for additional sound proofing and finishes.

    There is a wide range of heavyweight construction options available

    and all are fully able to meet the new standards for reduction of

    sound transmission as specified by the revised Part E of the Building

    Regulations. New separating/party wall minimum values for airborne

    sound insulation are 45dB for purpose-built dwellings and 40dB for

    relevant internal partitions within all house types, including detached

    properties. The robust standard details developed for concrete

    blockwork separating walls are designed to exceed these levels and

    so ensure compliance with Building Regulations and avoidance of the

    pre-completion testing of dwellings. A similar range of other concrete

    products and systems have robust details for separating floors for both

    airborne and impact sound requirements. Under Document E, over 60

    per cent of the approved systems or robust details for separating walls

    and floors use concrete and masonry.

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    Inherent flood resilience

    Climate change could not only mean hotter summers but also more

    extreme weather conditions. According to new research it could also

    mean more flash floods and severe storms. This will test the flood

    resilience and robustness of our built environment. Research, carried

    out by Newcastle University, found that by 2070 some parts of the UKcould see up to 8cm of rain in a day some 3cm more than is currently

    expected during a severe storm.

    The increased incidence of flooding and severe storms means that

    more homes will be at risk of flooding. Already in the UK some 570,000

    homes are estimated to be at a high flood risk. This compares to the

    202,000 predicted to be at risk in 2002. The figure looks set to rise due to

    the pressure to build on land liable to flood and due to the impacts of

    climate change.

    For house construction, the choice of building materials and finishes

    should maximise flood resilience by minimising damage and the time

    taken to refurbish. Masonry and concrete homes can be designed to be

    flood resilient to not absorb significant amounts of water or require any

    finishes, such as plasterboard, to be stripped off. In addition, concrete

    and masonry homes will not warp or rot following a flood and the

    damage caused by flooding is less likely to threaten the structural

    integrity of a modern heavyweight constructed home.

    Built-in fire resistance

    High-density housing raises concerns over the potential for the spread

    of fire. Concrete is a non-combustible material and has a slow rate of

    heat transfer which makes it an effective barrier to the spread of fire.

    Heavyweight homes exceed regulatory requirements because, unlike

    other construction materials, concrete has an inherent fire resistance ofup to four hours and does not produce smoke or toxic fumes. This means

    that heavyweight homes can offer a greater degree of protection from

    fires in neighbouring homes and longer times for people to escape. In

    addition, concrete homes are far more structurally sound after a fire and

    so can be quickly repaired rather than having to be demolished thus

    reducing the period required for alternative accommodation.

    Inherent robustness

    The predicted increase in severe storms could have a significant impact

    on our homes. Concretes inherent robustness enables buildings to

    better weather such high winds and rain.

    In addition, the robustness of heavyweight construction makes it a more

    secure and durable construction solution. For example, concrete and

    masonry party walls cannot be simply cut into for unauthorized entry.

    4 Concrete andMasonry Housing

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    5Concrete andMasonry Housing

    Energy-efficient housingHousing accounts for 27 per cent of all UK CO

    2emissions. Reducing this figure is a high priority and is being

    addressed with increased levels of insulation and airtightness in new build properties. The utilisation of thethermal mass in heavyweight construction can also help, and is provided in the form of concrete and masonry

    block walls and precast or in-situ concrete floors and wall panels.

    Embodied and operational CO2

    The use of concrete often raises questions regarding its embodied CO2, which can be slightly higher

    than that associated with some alternative materials, however, in reality the difference is relatively

    small when compared to lightweight systems. And, when you evaluate this in whole-life terms, the

    operational CO2

    savings provided by the heavyweight solution are much more significant.

    Case Description

    Lightweight External walls:timber framed wall with exterior brick and internal plasterboard finish

    Internal partitions: timber stud and plasterboardCeilings: timber with plasterboard/chipboard finish

    Ground floor: solid concrete/screedRoof: timber/tile

    Mediumweight As lightweight but with: External walls: mediumweight concrete blockcavity wall with exterior brick and internal plasterboard finish

    Medium-

    heavyweight

    As mediumweight but with:

    Ground floor ceiling: pre-cast concrete floor unitsGround floor partitions: mediumweight concrete block with

    plasterboard finish

    Heavyweight External walls: heavyweight concrete block cavity wall with exterior brickand fair-faced internal finishInternal partitions: heavyweight concrete block, fair-faced

    Ground and first floor ceilings: pre-cast concrete floor unitsGround floor solid floor construction and roof construction: as above.

    Figure 1: Cumulative CO2

    Emissions (Air-conditioned mode)

    To establish the facts of the embodied CO2

    versus operational CO2

    issue, The Concrete

    Centre commissioned research to examine

    performance of a simple semi-detached house

    built using a typical lightweight frame, with

    that of several heavyweight solutions with

    varying levels of thermal mass. The embodiedCO

    2for each option was calculated and thermal

    modelling was undertaken to see how each

    performed across the 21st century, taking

    account of the likely impacts of climate change.

    The results [1] showed that a typical concrete

    and masonry house with a medium level of

    thermal mass, has around four per cent more

    embodied CO2

    than an equivalent lightweight

    frame construction, but that this could be offset

    in as little as 11 years due to the energy savings

    provided by its thermal mass. Increasing the

    mass through additional concrete elements,

    such as precast upper floors, resulted in a longer

    offset period, but ultimately led to the lowest

    whole life CO2 emissions of all the options,with a saving in CO

    2over the 21st century

    approximately six times greater than the

    difference in its embodied CO2

    when compared

    to the lightweight

    frame solution.

    Due to the predicted increase in summer

    temperatures resulting from climate change,

    the lightweight home was found to need air-

    conditioning by 2021.This compared with 2041

    for the medium-weight home and 2061 for the

    medium-heavy and heavyweight homes. At

    the point that air conditioning was required its

    energy consumption was included in the overall

    energy use of the homes.

    The research highlights the inherent ability of

    masonry and concrete construction to provide

    a good long-term sustainable building option

    through energy efficient passive design and

    adaptability to the impacts of climate change.

    2000 2010 2020 2030 2040 2050 2060

    140

    120

    100

    60

    40

    20

    0

    80

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    6 Concrete andMasonry Housing

    Thermal mass and passive

    solar design

    The ability of thermal mass to avoid or reduce overheating problemsis being increasingly recognised. Perhaps less appreciated is its ability

    to save heating energy when used in passive solar design (PSD) which

    includes consideration of the buildings orientation, glazing provision

    and size plus appropriate shading.

    Using PSD enables concrete and masonry constructed dwellings to

    exploit their inherent thermal mass on a year-round basis. During the

    summer, heat is absorbed on hot days, helping to lower the internal

    temperature and prevent overheating problems. The stored heat is

    then removed by night-time ventilation. During the winter, the thermal

    mass will absorb solar gains through south facing windows, and slowly

    releases the heat at night. This process is effectively the same as that

    which occurs on summer nights, the only difference being that during

    the winter the stored heat is beneficial, so windows and openings are

    kept shut to minimise heat loss. Shutters and blinds can be used to

    prevent overheating in the summer and can also help reduce heat lossduring the winter.

    Part L of the Building Regulations and the Code for

    Sustainable Homes

    For dwellings the calculation methodology (known as SAP) used

    to evaluate Part L compliance assumes a fixed, comparatively low

    level of thermal mass for all types of construction. This assumption is

    currently being re-evaluated as part of the revision process that Part

    L is undergoing during 2009. The current consultation document

    suggests that thermal mass will be more accurately accounted for in the

    methodology. The benefits of optimisation of building form, fabric and

    orientation as a low cost design measure for reducing CO2

    emissions

    may therefore now be formally reflected in the revised edition of Part L1

    for dwellings, which will be introduced in 2010.

    Optimising the mass

    in floors

    Key concrete structural elements can be used to provide a mediumor high level of thermal mass, whilst also satisfying other design

    requirements such as acoustic performance, fire resistance and air

    tightness.

    Ground floors cast in situ slabs

    Ground floors can provide a good source of thermal mass in all types

    of dwelling providing the insulating layer is located below the slab. The

    Nu- Trench Floor System offers an effective way of achieving this, and

    uses expanded polystyrene for the insulating layer. To maximise heat

    exchange to and from the slab, the screed finish should be tiled rather

    than carpeted.

    An effective finish can be achieved by fixing materials such as high

    density concrete or terracotta tiles directly to the slab using a full bed

    mortar based adhesive. Alternatively, a vinyl floor covering will provide

    an intermediate level of admittance.

    Cast in situ floors work well with under floor heating, which are in

    turn ideally suited to high thermal mass dwellings. The pipe work for

    an under floor system is located within the screed, with the water

    distribution manifold located at low level in a cabinet or other discreet

    enclosure.

    Ground floors beam and block/precast hollowcore units

    To maximise the thermal mass, insulation must be located beneath the

    beams/units, not the usual location for this type of flooring. However,

    at least one proprietary hollowcore system is available where the

    insulation is already bonded to the underside of the unit. As with in-situ

    floors, the screed can be used to locate the pipe work for an under floorheating system. As the insulation is non-load bearing, a greater range of

    products can potentially be used. Recommendations for floor finishes

    are the same as for in-situ floors.

    Upper floors

    The benefit of installing a concrete upper floor was highlighted in a 2006

    study by Arup (see page 5) looking at the impact of climate change on

    comfort, which included a comparison of the additional passive cooling/

    heating effect provided by this approach as compared to a suspended

    timber flooring system. There are a range of solutions available; precast

    hollowcore units, solid precast units, precast soffit units with in-situ

    topping and in-situ flooring. The high quality fair-faced finish that can be

    specified for precast units makes them an ideal choice for high thermal

    mass dwellings as the soffit only requires painting, leaving the concrete

    fully exposed for good thermal linking.

    Installation of precast units can also be a fast and simple process. An

    alternative is to use modern formwork systems to provide shuttering

    for in-situ concrete. This too can provide high quality finishes and rapid

    construction.

    Benefits of designing with

    thermal mass

    Exploiting thermal mass on a year-round basis is not difficult,

    but does require consideration at the outset of the design

    process when requirements for the building form, fabric

    and orientation are being established. Providing this is done

    sympathetically, a more passive approach to design can realise

    benefits which include:

    Enhanced energy efficiency and carbon savings over the life

    of the building.

    Improved daylighting, ventilation and air quality.

    Optimal decrement delay (time lag) and decrement factor

    (heat flow) for reducing heat gains in summer.

    Good summertime comfort and a reduced risk of

    overheating.

    A measure of future proofing against the effects of a

    warming climate.

    Reduction in the need for more expensive low and zero

    carbon technologies to meet CO2

    targets.

    For more information on thermal mass download

    Thermal Mass Explainedfrom

    www.concretecentre.com/publications

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    7Concrete andMasonry Housing

    Case study: Barratts Green House, BRE,Watford

    The use of concrete in Barratts Green House prototype

    demonstrates how design quality and sustainability may be

    achieved in mainstream volume housebuilding of the future.

    Barratts new prototype house at the BRE Innovation Park

    in Watford is the first home built by a major housebuilder

    to achieve level 6, the highest level possible, using concrete

    under the Code for Sustainable Homes. The Code for

    Sustainable Homes sets out a grading system for new homes

    against nine categories: energy and CO2

    emissions; water;

    materials; surface water run-off; waste; pollution; health and

    wellbeing; management and ecology.

    For the Barratt Green House, the architect, Gaunt Francis,

    took the view that in-use energy over the lifetime of a typical

    UK house, 120 years, was much more significant than the

    initial embodied energy of the components which even for

    a standard blockwork house is just four per cent more than

    timber. Therefore, reducing future cooling requirementseasily offsets the small additional energy taken to produce

    the material. To exploit the benefits of concrete, including

    thermal mass, extensive use was made of it in the form of an

    in-situ ground-floor slab, precast concrete upper floors and a

    precast aerated concrete wall panel system.

    For more information on this case study, download

    Lessons Learned from the Barratt Green House from

    www.concretecentre.com/publications.

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    8 Concrete andMasonry Housing

    Heavyweight housing solutionsThe concrete industry offers a range of construction methods that are innovative and fast whilst offering

    traditional high performance and the inherent benefits of heavyweight construction. These constructionsolutions include blocks, precast and in-situ concrete. All are designed to deliver affordable and fast

    construction with long-term performance, to the higher code levels in the Code for Sustainable Homes.

    Masonry solutions

    The focus on efficiency and innovation has also been embraced by what

    is often viewed as the traditional method of house building: masonry.

    An example of the innovation in masonry construction is the use of

    aircrete blocks. This product is well placed to answer the requirement to

    reduce waste. Pulverised fuel ash, a by-product of coal-burning power

    stations, is used for their manufacture and the waste material generated

    during the production process is recycled back into the manufacturingprocess. The high compressive strength of aircrete means that only a

    single blockwork leaf for external walls is necessary. This enables fast

    construction times.

    Construction times are further accelerated by the use of thin-joint

    mortar. The 3mm mortar joints do not need to be trowel applied

    and it reaches full bond strength within two hours enabling more

    than one traditional lift in a day. Aircrete blocks are widely used for

    both load bearing and non-loading bearings walls and as infill units

    in beam and block floor systems. The use of aircrete provides an

    excellent combination of structural stability, acoustic insulation, energy

    conservation and fire resistance.

    Aircrete blocks

    A complete insulation solution is achievable using aircrete blocks. The

    inherent thermal qualities of these blocks provides a highly effective

    barrier against the penetration of moisture and frost. They can be used

    with full or partial fill insulation without necessarily increasing cavity

    widths, and if used below the ground can reduce heat loss by up to 25

    per cent. Whilst aircrete has a relatively low density (460-730 kg/m3), it

    still provides a useful amount of thermal mass.

    Large format blocks

    Large format blocks are produced from the same material as aircrete,

    and offer the same level of thermal performance. They are also suitable

    for the same applications as conventional sized aircrete blocks. Time and

    labour costs can be reduced when using large format blocks due to the

    speed of laying. They are suitable for use with conventional mortar or

    thin joint mortars.

    Full fill cavity wall: 100mm

    block and 100mm block

    with render

    Full fill cavity wall: brick and

    100mm block

    Insulating concrete formwork

    with brick slips

    Partial fill cavity wall: 100mm

    block and 100mm block

    with render

    Partial fill cavity wall: brick and

    100mm block

    Partial fill cavity wall: brick and

    100mm block

    Precast concrete

    sandwich panel

    Solid masonry wall: 215mm

    block, mineral fibre insulation

    and reinforced render

    Solid masonry wall: 215mm

    block, extruded

    polystyrene and reinforced

    external render

    Figure 2: External wall examples in concrete and masonry. For more information on these solutions, and their resulting U-values, download Energy and CO2: Achieving targets with

    concrete and masonryfrom www.concretecentre.com/publications

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    9Concrete andMasonry Housing

    The Nightingale Estate in Hackney is the largest residential tunnel form develop-

    ment in the UK. Residents in the new estate are already reporting how delighted

    they are living with robust concrete construction, mentioning sound insulationand reduced heating costs as major advantages.

    ICF consists of twin-walled expended polystyrene (EPS) panels or blocks that are

    built up to create walls.

    Insulating concrete

    formwork

    Fast construction is also a major benefit with insulating concrete

    formwork (ICF). The ICF provides permanent formwork for in-situ

    concrete structures and is left in place for the life of the building as

    thermal insulation. Used on the Continent and in North America for

    many years, in the UK ICF is increasingly being used by the self-build

    market and is attracting the attention of social housing providers and

    volume housebuilders.

    In essence, ICF consists of twin-walled expanded polystyrene (EPS)panels or blocks that are built up to create walls. This formwork is then

    filled with ready-mixed concrete to build a structure ready for the next

    floor or roof construction. The EPS remains in place to provide complete

    thermal insulation for the walls of the finished building and to provide a

    uniform surface ready for the direct application of most internal finishes

    and external cladding systems.

    For more information on ICF, download Insulating Concrete Formwork

    from www.concretecentre.com/publications.

    Tunnel form

    Tunnel form is a formwork system that allows the on-site casting of

    walls and slabs in one operation on a daily cycle. During the tunnel form

    process, a structural tunnel is created by pouring concrete into highquality formwork to make the floor and walls. The space formed can

    span from 2.4m to 6.6m and can be easily sub-divided to create smaller

    rooms. Where longer spans of up to 11m are required, the tunnel form is

    extended using a mid-span section. After 24 hours, the formwork is moved

    horizontally so that another identical tunnel can be formed. When the

    storey has been completed, the process is repeated on the next floor.

    The system creates an efficient load-bearing structure that is particularly

    well suited for repetitive cellular construction such as residential

    apartment blocks. The solid monolithic structure can be used for

    small blocks of six apartments or for residential towers of 40 or more

    storeys high and the accuracy of the system suits the installation of

    prefabricated elements such as cladding panels and bathroom pods.

    Tunnel form combines the speed, quality and accuracy of off-siteproduction with the flexibility of on-site cast construction.

    For more information on tunnel form, download High Performance

    Buildings using Tunnel Form Concrete Construction from

    www.concretecentre.com/publications.

    Aggregate blocks

    A wide range of aggregate blocks are available, with densities varying

    from around 1400kg/m3 for a lightweight block to around 2000kg/m3

    for a heavyweight block, which can provide a very high admittance of

    around 6W/m2K when used with a wet plaster finish. To ensure good

    thermal linking between the walls and internal space, a fair-faced or awet plaster finish is the most effective option. Although wet plaster is

    normally slower to apply than plasterboard, the introduction of sprayed

    or projection plaster has changed this. It is fast to apply and better than

    plasterboard at sealing walls, improving both air tightness and sound

    insulation (although allowance has to be made for drying out time).

    Thin-joint blockwork

    More commonly associated with aircrete/aerated concrete blockwork, the

    thin joint system permits a faster build time than standard 10mm joints.

    The recommended height of build per day for standard 100mm blocks

    with 10mm joints would be no more than seven courses (1.5metres). With

    the thin joint system special mortars are used which typically enable three

    metres (or one storey height) per day to be achieved.

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    10 Concrete andMasonry Housing

    In addition, basements can reduce the energy consumption of houses.

    Heat losses through basements floors and walls are less than those at

    ground and upper floor levels. Research carried out by the BRE found

    that given two houses of the same floor area and construction, the one

    with a basement would be 10 per cent more energy efficient. Basement

    living space also offers better sound insulation. This makes the lower

    ground floor an ideal location for a study, play or work room.

    For more information on concrete basements visit

    www.basements.org.uk

    Flood prevention

    using SUDS

    Sustainable Urban Drainage Systems (SUDS) is a design philosophy

    which uses a range of techniques to manage surface water by

    attenuation and filtration with the aim of replicating, as closely as

    possible, the natural drainage prior to a site being developed.

    A useful and versatile SUDS technique is Concrete Block Permeable

    Paving (CBPP). This provides important attenuation and pollution

    source control and in addition CBPP does not need additional land take

    unlike soft SUDS landscaping techniques which may require wetlands

    and ponds. CBPP works by allowing water to pass through the surface

    between each block and into the underlying permeable sub-base. Here,

    it is stored and released slowly either into the ground, to the next SUDS

    management stage or to a drainage system.

    An alternative concrete-based SUDS system is pervious concrete. This is

    a special ready-mixed concrete that has a single-sized coarse aggregate,

    a low fines content, and typically a 20 per cent voids content. A SUDS

    system using pervious concrete in the surface layer is designed in the

    same manner as a concrete block permeable pavement.

    For further information on SUDS visit www.paving.org.uk

    Crosswall

    A precast concrete cellular system is crosswall, which provides the

    benefits of speed and on-site productivity.

    The components - floors and load-bearing walls, with preformed

    window apertures - combine swiftly to form room shells. Concrete

    finishes to walls and soffits are of good quality as a result of their

    production in steel moulds and enable minimum plastering or finishing

    with directly applied coatings.

    Crosswall construction delivers buildings that are fast to erect, durable,

    have excellent inherent fire resistance and acoustic performance and are

    virtually maintenance free.

    For more information on crosswall, download Crosswall Construction

    from www.concretecentre.com/publications.

    TwinwallTwinwall construction is a hybrid combination of precast and in-situ

    concrete. It provides fast and efficient construction that capitalises on

    the benefits of both factory and on-site production.

    Each wall panel consists of two skins of precast reinforced concrete

    which are temporarily held in position by lattice girder reinforcement.

    The concrete skins are effectively permanent formwork, with the benefit

    that they are used structurally in the finished building. The weight of a

    twinwall panel the same size as a fully precast panel is reduced, which

    permits the use of larger panels or smaller cranes. The wall panels are

    placed into position using similar methods to the crosswall elements,

    For the floors, lattice girder slabs are used. These have a thin precast

    concrete soffit often called the biscuit, which includes the bottom

    reinforcement and acts as permanent formwork. Once the walls and

    floor units are positioned, reinforcement for the slab and to tie the walls

    and slabs together is fixed. In-situ concrete is then poured into the void

    in the twinwall panels and on top of the biscuit of the lattice girder slabs.

    Basements

    Limited land availability means that new homes will have to use space

    more efficiently.

    The provision of a basement can provide 50 per cent more living space

    for a two-storey house. This means more living space for a smaller foot

    print. In mainland Europe and throughout America, basements are

    seen as a way forward to maximise land-use for a small cost increase.

    Sloping sites are ideally suited to provision of semi-basements with

    one side below ground and the other at ground level. On brownfield

    sites, the poor ground conditions encountered can often require deep

    excavations and foundations and basements can easily be provided in

    this economically excavated space.

    Adding a basement could provide as much as 50 per cent more floor area for a

    typical two-storey dwelling and 100 per cent for a bungalow.

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    11Concrete andMasonry Housing

    Summary

    Concrete and masonry offer a wide range of affordable, sustainable and efficient construction solutions for

    social housing to the highest levels of the Code for Sustainable Homes, each of which come with the full

    range of inherent long-term performance benefits including energy efficiency, robustness, low maintenance,

    enhanced sound insulation and security, fire resistance and flood resilience.

    The whole life performance and wide range of benefits of heavyweight construction makes it particularly well

    suited for housing solutions. These solutions are long term and holistic due to their ability to meet economic,

    environmental, social and aspirational requirements.

    References and further reading

    1. Hacker J et al, Embodied and Operational Carbon dioxide Emissions from Housing: A Case Study on the Effects of Thermal Mass and Climate Change, Energy

    and Buildings 40 (2008) 375-384. For further information see www.concretecentre.com/greenhomes

    The Concrete Centre has published a number of titles that are relevant to social housing. These include:

    Concrete and the Code for Sustainable Homes,The Concrete Centre, 2009

    Energy and CO2: Achieving Targets with Concrete and Masonry, The Concrete Cent\re, 2008

    How to Build Flood Resilient Homes using Concrete and Masonry, The Concrete Centre, 2009

    Thermal Mass for Housing,The Concrete Centre, 2006Concrete and Fire Safety,The Concrete Centre, 2008

    Residential Cellular Buildings,The Concrete Centre, 2008

    Design and Construction using Insulating Concrete Formwork, The Concrete Centre, 2007

    Thermal Mass Explained,The Concrete Centre, 2009

    Concrete and the Green Guide, The Concrete Centre, 2009

    For more information on these titles and many more, visit www.concretecentre.com/publications

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    12/12

    www.concretecentre.com

    Printed onto 9Lives silk comprising 55% recycled fibre with 45% ECF virgin fibre. Certified by the Forest Stewardship Council.

    All advice or information from MPA -The Concrete Centre is intended only for use in the UK by those who will evaluate the significance and limitations of its contents and

    take responsibility for its use and application. No liability (including that for negligence) for any loss resulting from such advice or information is accepted by Mineral Prod-

    ucts Association or its subcontractors, suppliers or advisors. Readers should note that the publications from MPA - The Concrete Centre are subject to revision from time to

    time and should therefore ensure that they are in possession of the latest version.

    The Concrete Centre,

    Riverside House,

    4 Meadows Business Park,

    Station Approach, Blackwater,

    Camberley, Surrey GU17 9AB

    Ref. TCC/04/08

    ISBN 978-1-904818-77-9

    First published 2009 MPA - The Concrete Centre 2009

    The Concrete Centre is part of the Mineral

    Products Association, the trade association for the

    aggregates, asphalt, cement, concrete, lime, mortar

    and silica sand industries.

    www.mineralproducts.org


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