1
Application of AircreteApplication of AircreteBlocksBlocks
2
ObjectiveObjective
To provide theTo provide the specifier specifier with a with agreater understanding of aircretegreater understanding of aircreteblocks:blocks:
•PropertiesProperties•CapabilitiesCapabilities•ApplicationsApplications•BenefitsBenefits
3
History of AircreteHistory of Aircrete
•Developed in Sweden in 1924Developed in Sweden in 1924
•Floor and roof screed in 1949Floor and roof screed in 1949
•Aircrete blocks first used in late 1950’sAircrete blocks first used in late 1950’s
•Over 225 manufacturing plantsOver 225 manufacturing plants
worldwide: Europe, Asia, Middle East,worldwide: Europe, Asia, Middle East,
Africa, America and AustraliaAfrica, America and Australia
•These plants produce over 30 million mThese plants produce over 30 million m33
of material per yearof material per year
Overview: A brief explanation of the technicaldevelopment of Aircrete
History of how Aircrete was developed as blocks.- developed as an alternative to building with timber
Figures show the success of Aircrete blocks throughoutthe World. 30 million cube = 30 bn 100mm blocks
4
UK MarketUK Market
•Used by major housebuilders throughoutUsed by major housebuilders throughout
the countrythe country
•Aircrete block sales areAircrete block sales are approx approx. 2.9. 2.9
million mmillion m33 per annum per annum
•Aircrete accounts forAircrete accounts for approx approx.1/3 of all.1/3 of all
concrete blocks used in the UKconcrete blocks used in the UK
Emphasize the success of aircrete blocks in the UKmarket.
5
Production ProcessProduction Process
PFAslurry
Rising andinitial set
Firstwire cut
Secondwire cut
High pressure steam curing
Storage DispatchPackaging
Mixing
MouldsPouring
Mould sidesremoved
AluminiumLime
Cement
Brief explanation of the production process I.e. Ingredients, mixing,cooking, cutting process and packaging.
•Mix Pulverised fuel ash (PFA) and/or sand* with water to form a slurry.(*Sand is ground at Westbury)
•Slurry is heated and mixed with Cement & lime.
•Add a small quantity of aluminium powder.
•Pour into moulds and is left to set for 30-40 minutes
•Quality check.
•Hydrogen causes the mix to bubble up to full density.
•Quality check
•Tip slab from the mould*(temp is about 600c. Slab is also self supporting)*Boro Green only (sides of mould removed in Pollington & Westbury)
•Cut slab into block size and remove top and sides
•Into autoclave for approx 9-12 hours at 2000C and 200 psi
•Quality check and trim off the bottom of the slab.
•Wrap and strap. Note the batch number on the wrapper.
LEAVE STANDING 24Hrs BEFOR USE.
6
Physical attributes of AircretePhysical attributes of Aircrete
•Thermally efficientThermally efficient•StrongStrong•Lightweight - one person lift in most casesLightweight - one person lift in most cases•Acoustic propertiesAcoustic properties•Resistant to the passage of moistureResistant to the passage of moisture•Fire resistantFire resistant•WorkabilityWorkability•Frost resistantFrost resistant•Resistant to sulfate attack (up to Class 4)Resistant to sulfate attack (up to Class 4)
Generic benefits of Aircrete. These features are true forall products in the range
Highlight the good performance of the blocks in each ofthese points
Many product features are due to composition of producteg. cellular structure
Emphasis on:Lightweight - The cellular structure of the materialensures a lightweight construction. Duringinstallation, most aircrete blocks can be lifted withone hand providing significant productivityadvantages.
Workability - I.e. cutting & chasing using hand tools
NB, Resistant to sulfate attack up to and including Class4 soil conditions
7
Properties of Aircrete BlocksProperties of Aircrete Blocks
* Equivalent to 10N/mm2 (Exclusive to Celcon)
LowLowDensityDensity
MediumMediumDensityDensity
HighHighDensityDensity
HighHighDensityDensity
ThicknessThickness (mm)(mm) 100 -100 - 265 265
75 –75 – 355 355
90 –90 – 355 355
90 –90 – 355 355
CompressiveCompressiveStrengthStrength (N/mm(N/mm22))
2.82.83.5#3.5# 4.04.0 7.07.0 8.4*8.4*
DensityDensity(kg/m(kg/m33)) 460460 620620 750750 750750
ThermalThermalConductivityConductivity (W/(W/mK)mK) 0.110.11 0.150.15 0.190.19 0.190.19
3.5N Dense block: Thermal Conductivity 0.47
7.0N Dense block: Thermal Conductivity 1.06
# Made to order product only
Chart to show the comparison between types of aircreteblock
Table shows that the higher the compressive strength, theless thermally efficient the blocks are.
The figures below the chart show the thermalperformance of dense blocks. The poor performancecompared to aircrete needs to be highlighted (with thegreater need for thicker insulation to meet Regs).
Emphasize the Made to order only of Solar 3.5N blocks
and that the 8.4 is an exclusive product to Celcon
8
IdentificationIdentification
NormalV-Key
BoroughGreenV-key
NormalV-Key
BoroughGreenV-key
SOLARSOLARThe V-key coversapprox. 2/3 of theblock face.
STANDARDSTANDARD The V-key covers theblock face completely
Each manufacturer has it’s own way of identifying theirblocks, this shows how we identify ours.
9
IdentificationIdentification
NormalV-Key
BoroughGreenV-key
NormalV-Key
BoroughGreenV-key
HI-SEVENHI-SEVENV-key covers blockface completely,plus a black stripeto one end
HI-HI-TENTEN ee
V-key covers blockface completely,plus a red stripe toone end
Each manufacturer has it’s own way of identifying theirblocks, this shows how we identify ours.
10
Relevant Design CriteriaRelevant Design Criteria
•StrengthStrength
•Thermal EfficiencyThermal Efficiency
•PricePrice
•DurabilityDurability
•BuildabilityBuildability
•FixingFixing
•Manual HandlingManual Handling
Highlighting the key factors that may effect the choice ofproduct/construction method.
NB, Strength: Could also mention the load bearingcapabilities of the base.
Thermal Efficiency: Well insulated walls leads to greaterenergy efficiency within the building eg reduction in fuelcosts, smaller boiler can be specified.
Price: Not just material costs, but also laid costs
Manual Handling: Majority of blocks fall below 20kgrecommendation for repetitive lift.
11
ApplicationsApplications•Below GroundBelow Ground
•FloorsFloors
• Inner Leaf of Cavity WallInner Leaf of Cavity Wall
•External Leaf of Cavity WallExternal Leaf of Cavity Wall
•Solid WallsSolid Walls
•Party WallsParty Walls
• Internal PartitionsInternal Partitions
Brief explanation of the general applications of aircreteblocks, these are covered in greater detail later on in thepresentation
NB: Other possible use of blocks are as a protectivecladding from fire for other forms of construction egsteel frames.
12
Chandlers Building Supplies
Architect, Graham Middle Associates specified aircrete 7Nblocks to provide extra strength for Chnadlers Building Supplies’new HQ in Ringmer, East Sussex
7N blocks were specified as the first floor is incorporated withinthe the roof space, therefore increasing the load at the top of theconstruction. As a result large first floor spans reinforced withsteel were needed to support the floor structure and aircrete 7Nprovided external wall strength at areas of load-bearing tosupport both the floor and the roof.
Standard aircrete blocks were also specified for the external andpartition walls, as they provide good acoustic performance - animportant consideration when designing office workspace.
The thermal efficiency of the blocks means the HQ has anaverage wall U-value well within the Building Reg requirements.
13
Medium Density (Standard)Medium Density (Standard)Nominal DensityNominal Density 620 kg/m³620 kg/m³Compressive StrengthCompressive Strength 4.0 N/4.0 N/mm²mm²K or K or λ ValueValue 0.15 W/0.15 W/mKmKBBA Certificate BBA Certificate 86/168986/1689SizeSize 440x215mm440x215mmThicknessesThicknesses 75 - 355mm75 - 355mmAlso available as:Also available as:Flooring Block - 440 x 560 x 100mmFlooring Block - 440 x 560 x 100mmJumbo Units: 440 x 430mm (100 - 125mmJumbo Units: 440 x 430mm (100 - 125mmthick)thick)
Explanation of product features for Standard 4N/mm2
blocks:
Strength figures
Thermal Performance figures
BBA certificate number
Highlight the additional product ranges available withthis strength. These are again covered in greater detaillater on (including BBA certificate number)
Foundation blocks are covered latter in the presentation
14
Applications for 4N/mmApplications for 4N/mm22 Aircrete Blocks Aircrete Blocks
•HousingHousing•Commercial & Industrial BuildingsCommercial & Industrial Buildings
–PartitionsPartitions–Infill for framesInfill for frames–Simple finishesSimple finishes
InternalInternal External External leaf ofleaf of leaf ofleaf of
Cavity Cavity CavityCavity SolidSolid Separating/Separating/ Multi-Multi- SuspendedSuspended
WallsWalls WallsWalls WallsWalls Party WallsParty Walls PartitionsPartitions StoreyStorey FoundationsFoundations FloorFloor
** ** ** ** ** ** ** **
Table to show all the applications of 4N/mm2 aircreteblocks
Plus highlighting the advantages of use in commercial &industrial buildings (especially Jumbo Units which areideal due to increased productivity)
Finishes: Areas where aesthetics are not importantaircrete blocks can be painted, or left unfinished.
Foundations: Point out that regular aircrete blocks can beused in cavity foundation construction, with lean mixinfill. Solid Foundation blocks are dealt with later.
15
Low DensityLow Density
Solar 2.8 & 3.5*Solar 2.8 & 3.5*Nominal DensityNominal Density 460 kg/m³460 kg/m³Compressive StrengthCompressive Strength 2.8 or 3.5* N/2.8 or 3.5* N/mm²mm²K or K or λλ ValueValue 0.11 W/m K0.11 W/m K
BBA Certificate 95/3096 BBA Certificate 95/3096SizeSize 440 x 215mm440 x 215mmThicknessesThicknesses 100 - 355mm100 - 355mm
Also available as Jumbo Units 440 x 430mmAlso available as Jumbo Units 440 x 430mm(100 - 140mm thick)(100 - 140mm thick)
* Special Order* Special Order
Explanation of product features for Solar range 2.8 or3.5N/mm2 blocks:
Strength figures
Thermal Performance figures
BBA certificate numbers
Highlight that Jumbo Units (discussed in greater detaillatter on) are available as Solar
16
Applications for Aircrete 2.8N/mmApplications for Aircrete 2.8N/mm2 2 BlocksBlocks
•HousingHousing
•CommercialCommercial
•Clear Cavity?Clear Cavity?
InternalInternal External External
leaf ofleaf of leaf ofleaf of
Cavity Cavity CavityCavity SolidSolid Separating/Separating/ Multi-Multi- SuspendedSuspended
WallsWalls WallsWalls WallsWalls Party WallsParty Walls PartitionsPartitions StoreyStorey FoundationsFoundations FloorFloor
** ** **
Table to show all applications for 2.8N/mm2 aircreteblocks
Clear Cavity?: Discussing whether you need additionalinsulation when using Solar blocks
Refer to Book of Blocks for possible cavity solutions
Other possible use: Multi-Storey construction which isnon-loadbearing I.e. in steel framework.
Cavity Foundations: Solar blocks can only be used forthe inner leaf of a foundation.
17
Hi-DensityHi-DensityNominal DensityNominal Density 750 kg/m³750 kg/m³K or K or λ ValueValue 0.19 W/0.19 W/mKmKBBA Certificate 90/2462BBA Certificate 90/2462SizeSize 440 x 215mm440 x 215mmThicknessesThicknesses 100 - 355mm100 - 355mmAlso available as Jumbo Units 440 x 430 x 100mmAlso available as Jumbo Units 440 x 430 x 100mmHi-SevenHi-SevenCompressive StrengthCompressive Strength 7.0 N/7.0 N/mm²mm²
Hi-Hi-TenTenee
Compressive StrengthCompressive Strength 8.4 N/8.4 N/mm²mm²10 N/10 N/mm²mm² can be achieved in can be achieved incertain design situations.certain design situations.Unique to CelconUnique to Celcon
Explanation of product features for Hi-Strength 7.0 &8.4N/mm2 blocks:
Strength figures
Thermal Performance figures
Highlight Jumbo Units
Plus explanation on Hi-Tene blocks (explaining the lastparagraph on design situations)
Foundation blocks are covered latter on in thispresentation.
18
Applications for Aircrete 7 & 10N/mmApplications for Aircrete 7 & 10N/mm22
BlocksBlocks
•Developed for buildings 3+Developed for buildings 3+ storeys storeys high, high,industrial, commercial and housingindustrial, commercial and housing
•Compatible with lower strength blocksCompatible with lower strength blockselsewhere on the project, maintainingelsewhere on the project, maintainingcontinuitycontinuity
InternalInternal External External leaf ofleaf of leaf ofleaf of
Cavity Cavity CavityCavity SolidSolid Separating/Separating/ Multi-Multi- SuspendedSuspended
WallsWalls WallsWalls WallsWalls Party WallsParty Walls PartitionsPartitions StoreyStorey FoundationsFoundations FloorFloor
** ** ** ** ** ** ** **
Table to show all the applications of 7 & 10N/mm2
aircrete blocks
First bullet point is self explanatory
Second bullet point explains that these blocks can beused in conjunction with other types of Celcon block onsite.
Foundations: Again mention cavity construction.
19
Hi-Strength for Tonbridge & Malling Housing Association
Aircrete 10N, 7N and standard blocks were specified for thisresidential development in Tonbridge, Kent.
The development consists of a four-storey block of 21 units, anda three-storey block of 14 units.
To provide load-bearing strength, Hi-Ten were used in thefoundations and through to first floor level. Aircrete standardand 7N blocks were incorporated throughout the upper levels.The partially filled cavity walls provided a U-value of0.39W/mK2.
Each storey is equipped with a lift, the lift shaft being constructedfrom 7N aircrete blocks to provide the required structuralintegrity.
20
Foundation BlocksFoundation Blocks
•Sizes 250 up to 355mm thickSizes 250 up to 355mm thick
•Foundation 4 N/mmFoundation 4 N/mm22 ( (BBA 86/1689)BBA 86/1689)
•Foundation 7 or 10Foundation 7 or 10e. e. N/mmN/mm2 2 (BBA 90/2462)(BBA 90/2462)
•Less than half the weight of equivalentLess than half the weight of equivalent
aggregate blocksaggregate blocks
•Supports cavity or solid wallsSupports cavity or solid walls•Faster laying rateFaster laying rate
• Improves floor U-ValueImproves floor U-Value•Saves cost of:- cavity ties, lean mix cavity fillSaves cost of:- cavity ties, lean mix cavity fill
Foundation Blocks - Size of blocks
- Strength of blocks
- BBA cert number
- Weight advantages (compared size like for like)
- Cost savings
- Improved thermal performance, especially when used with Aircrete Flooring blocks (up to 25% better)
Laying Rate:
Foundation blocks are roughly three times quickerto lay and one man can do the job.
21
Laying Rates for Foundations*Laying Rates for Foundations*
Brick (2 leaves)Brick (2 leaves) 2.95m2.95m22/hr/hr
Dense block (2 leaves)Dense block (2 leaves) 6.75m6.75m22/hr/hr
Foundation blockFoundation block 11.6m11.6m22/hr/hr
**Based on 450mm deep foundationBased on 450mm deep foundation
Not just rates of laying, but additional costs saved:
1) Mortar for brick and dense block
2) Lean mix for cavity fill
3) Cavity Ties
22
Foundation BlocksFoundation Blocks
•Sulfates (up to &Sulfates (up to &including Class 4including Class 4soil conditions)soil conditions)
•Frost ResistantFrost Resistant
•MortarsMortars
Product features that show why aircrete Foundationblocks can be used below DPC level
Plus advice on the type(s) of mortar that should be usedbelow ground level, linking to a chart to show mortarstrengths
23
Flooring BlocksFlooring Blocks
•440 x 560mm 4N/mm440 x 560mm 4N/mm22 Compressive CompressiveStrengthStrength (BBA(BBA 90/2467) 90/2467)
•Developed for use within pre-castDeveloped for use within pre-castconcrete suspended floor beamsconcrete suspended floor beams
•Using Aircrete in beam &Using Aircrete in beam & block flooring can help block flooring can help improve U-value improve U-value
•Fewer beams requiredFewer beams required
Properties and benefits of aircrete Flooring blocks
Emphasis on the thermal performance benefitscompared to solid concrete floors - “U-value” is a linkto a graph comparing U-values for Beam & aircreteblock infill and Solid concrete floors.
Fewer beams required when flooring blocks are laidalong the 560mm width. Resulting in cost savings
24
Floor U-valuesFloor U-values
0
0.1
0.2
0 .3
0 .4
0 .5
0 .6
0 .7
0 .8
0 .9
1
0 0.1 0.2 0 .3 0 .4 0 .5 0 .6 0 .7 0 .8 0 .9 1 .0
P / A
U-v
alu
e
Beam & Ce l con b l ock f l oo r ,
o n 250mm t h i c k C e l c o n
Foundat ion b locks ,
4 5 0 m m b e l o w g r o u n d
So l id F loo r Beam & Ce lcon b lock i n f i l l
0.5 P/A is typical for housing
[NB, Exposed Perimeter length (P) / Floor Area (A)]
Not just benefits of having a thermal block but also theimproved performance of Beam & Block with thermalbuffer zone under floor void
25
FloorsFloors
Additional benefits of using aircrete Additional benefits of using aircreteblocks as beam infill are :-blocks as beam infill are :-
•Faster layingFaster laying
•Cost savingsCost savings
•Lower dead weightLower dead weight
•Easily cutEasily cut
Note:- Regular size blocks (440x215)Note:- Regular size blocks (440x215) can also be used as infill can also be used as infill
Faster Laying: Larger size flooring blocks result in lessblocks to be laid. Still a one man lift
This leads to cost savings, as well as the point on theprevious slide about less beams required
Lower dead weight, allows for longer beam spans, orlighter beam sections can be used.
Highlight the fact that standard size blocks can be used,but more productivity benefits are gained by using theFlooring blocks.
26
Carkeek Developments - Plymouth
Carkeek Developments needed an aircrete solution that wouldachieve a SAP rating of over 75 for its Western ChallengeHousing project in Plymouth.
All dwellings feature aircrete 275mm Foundation blocks, andthese combined with 100mm infill blocks for the beam & blockfloor, helped to achieve a floor U-value of 0.35W/mK2
The properties’ clear cavity walls are constructed using aircrete125mm low density (solar) blocks for the inner leaf and 100mmstandard blocks for the outer leaf - achieving a high level ofinsulation without the need for any additional insulation.
27
Thin-Joint SystemThin-Joint System•440 x 430mm Jumbo Units or standard size440 x 430mm Jumbo Units or standard sizeblocksblocks
•2-3mm mortar joint(Celfix Mortar)2-3mm mortar joint(Celfix Mortar)
•Productivity is increasedProductivity is increased
compared to conventional block layingcompared to conventional block laying
•Up to 10% enhancement in wall U-valueUp to 10% enhancement in wall U-value
•Fast & cost effective way of buildingFast & cost effective way of building
•Approved by BRE & BBAApproved by BRE & BBA
•Separate CPD Seminar available on Thin-JointSeparate CPD Seminar available on Thin-Joint
Bullets to list components of system & main advantages
Productivity: larger blocks-faster laying rate, greaterbond strength, build higher in a day
U-value: Thinner mortar joint, greater area of blockwhich is better insulant than conventional mortar
Build Quality: Inner leaf can be built up first, eliminatingproblem of mortar snots on wall ties, cleaner cavities.
Refer them to our CPD Seminar (available soon) on
thin-joint for further information
28
Cavity WallsCavity Walls
•Aircrete blocks are used extensively inAircrete blocks are used extensively inconstruction for :-construction for :-–Structural supportStructural support–Thermal insulationThermal insulation
•Low Density (Solar) blocks are ideal forLow Density (Solar) blocks are ideal for
clear cavity solutionsclear cavity solutions
•Medium Density (Standard) is used inMedium Density (Standard) is used in
partial or fully filled constructions.partial or fully filled constructions.
•See technical literature for solutionsSee technical literature for solutions
Solar - Ideal for clear cavity solutions because ofthermal properties of blocks. This is further enhanced ifSolar is used in both leaves of the wall.
E.g. Brick Outer-50mm cavity-115mm Solar-27mmThermalboard plus = 0.45W/mK2
or
16mm render-115 Solar-50mm cavity-115mm Solar-9.5Plasterboard on dabs = 0.43W/mK2
Standard - Thickness of insulation can be reduced whenusing Standard compared to dense aggregate blocks.NB: Clear cavity is possible with Standard if thermalboard lining is used
U-values are contained in the Celcon “Book of Blocks”see pages 39 - 43
29
External Solid WallsExternal Solid Walls
•265mm Low Density blocks (Solar)265mm Low Density blocks (Solar)commonly usedcommonly used
•Meets the thermal requirements of theMeets the thermal requirements of theBuilding Regulations without addedBuilding Regulations without addedinsulationinsulation
•Variety of finishesVariety of finishes–RenderingRendering–Timber claddingTimber cladding–Tile hangingTile hanging
Using 265mm Solar in a solid wall is the simplest way tomeet the building regs without using additionalinsulation.
The finishes used both internally and externally willaffect the U-value. With the exception of render &sand/cement plaster used in conjunction, they all fallbelow 0.45W/mK.
30
Internal partition wallsInternal partition walls
•100mm Medium Density (Standard)100mm Medium Density (Standard)
generally usedgenerally used
• Improved sound insulationImproved sound insulation
•Very light weight compared to denseVery light weight compared to dense
block wallsblock walls
•Greater benefitsGreater benefits
using Thin-Jointusing Thin-Joint
Structure of blocks i.e air bubbles, mean that soundinsulation is much better when compared to timberstud/plasterboard (as per example on next slide)
Lightweight means that blocks are laid quicker (blocksare easy to handle)
Thin-Joint: greater productivity, further improvements insound insulation, & build time meaning that the wall canbe finished more quickly.
31
Food Sciences Building University of Nottingham
Standard aircrete was specified to help create the futuristic designof the new Food Sciences Building at the University ofNottingham. The £2.2million contract was undertaken byThomas Fish Construction.
All partition walls were formed using standard aircrete blocks toreduce sound transmission from room to room. (39dB comparedto 33dB for plasterboard on studwork option).
The blocks’ light weight was also a factor in their specificationbecause of loadbearing restrictions on the steel frame.
32
Sound Insulation Equation:Sound Insulation Equation:
Careful DesignCareful Design++
Separating Wall ConstructionSeparating Wall Construction++
Associated structureAssociated structure++
Proper site practiceProper site practice==
GOOD SOUND INSULATIONGOOD SOUND INSULATION
The sound performance of the wall will be dependant onthe above equation irrespective of materials.
Careful Design - location of sockets, joists built in or not.
Separating Wall Const. - Cavity walls will generally perform better than solid.
Associated Structure - floor construction, flanking wall construction
Proper Site Practice - Good workmanship etc..I.e. mortarjoints fully filled
33
Party WallsParty Walls
•Typically Standard or 7N blocks usedTypically Standard or 7N blocks used•Cavity and Solid wall constructionCavity and Solid wall construction•Covered by BBA Certificate for meetingCovered by BBA Certificate for meetingBuildingBuilding Regs Regs. requirements. requirements
•Plaster (or plasterboard finish for cavityPlaster (or plasterboard finish for cavitywall)wall)
•Check with TechnicalCheck with Technical Hotline for precise Hotline for preciserequirementsrequirements
Emphasize that only wet plaster can be used on solidwall construction.
34
Fire ResistanceFire Resistance
Class O spread of flameClass O spread of flame
100mm Standard block:100mm Standard block:–Loadbearing wall = 1 hourLoadbearing wall = 1 hour–Non-loadbearingNon-loadbearing = up to 4= up to 4wallwall hours hours
Aircrete blocks have excellent resistance to fire.
Can be used as fire-break walls
Also can be used as a protective cladding for other formsof construction eg steel frames
Figures above taken from the BRE report
35
Movement JointsMovement Joints
•Aircrete block Walls in excess of 6mAircrete block Walls in excess of 6mshould be designed as a series of panels,should be designed as a series of panels,separated by movement joints at max.separated by movement joints at max.6m6m centres centres (if (if un un-reinforced) and 3m-reinforced) and 3mfrom a bonded return.from a bonded return.
BJR used up to max of: 6m un-reinforced
approx. 9m if reinforced every 3rd course
approx.11m if reinforced every other course
approx. 13m if reinforced every course
36
Bed-joint ReinforcementBed-joint Reinforcement
•Used in:Used in:–Areas of high stress e.g. openingsAreas of high stress e.g. openings–First two courses of a wall supported by aFirst two courses of a wall supported by a
floor which is subject to deflectionfloor which is subject to deflection
•Adequate length toAdequate length to distribute stresses distribute stresses•Use masonry gradeUse masonry gradereinforcementreinforcement
•Dissimilar materialsDissimilar materials
Adequate length to distribute stresses to nearbymovement joints. Or into adjacent areas of blockwork,extending 600mm each side of the opening.
Masonry grade reinforcement should be used in all cases,plastering grade types are NOT suitable (eg Expamet).
If dissimilar materials bear onto Celcon blocks (floorunits, precast concrete beams, lintels), a slip plane shouldbe provided at the bearing eg DPC material
37
Wall TiesWall Ties•Flexible wall ties with max. spacing: Flexible wall ties with max. spacing:
900mm horizontally900mm horizontally450mm vertically450mm vertically
NB.For the Thin-Joint System Helical ties should beNB.For the Thin-Joint System Helical ties should be used used
Ties should be evenly distributed over the wall area,normally in a staggered pattern
Additional ties should be provided at:•Within 225mm of the vertical edge of all window & door openings
•At vertical unreturned edges, including movement joints
•At sloping unreturned edges, such as at the roof verge
38
Internal FinishingInternal Finishing
Types:Types:–PlasterPlaster–DryliningDrylining–TilesTiles
•PreparationPreparation•SpecificationSpecification•ApplicationApplication
This slide really used as an overview for the followingone.
Preparation: Block surfaces should be clean of dust,loose particles or contamination before application offinish
39
Finishes - InternalFinishes - Internal• Plasterboard on dabs Plasterboard on dabs• Lightweight plaster - min 13mm thick Lightweight plaster - min 13mm thick
– Joints should be recessed Joints should be recessed• Dense plaster - min 13mm thick Dense plaster - min 13mm thick
– Mix to be 1:1:6 (C:L:S) Mix to be 1:1:6 (C:L:S)– Blockwork may need to be wetted to balance Blockwork may need to be wetted to balance
the initial suctionthe initial suction– Joints should be recessed Joints should be recessed
•Thin coat spray plaster can be applied toThin coat spray plaster can be applied toThin-Joint wallsThin-Joint walls
•TilingTiling– Direct to wall if blockwork plumb Direct to wall if blockwork plumb
• Painted Painted
Plasterboard: Standard and laminated thermal boards can bebonded directly to the blockwork.
Standard boards can be fixed using plaster dabs
Thermal boards should be fixed using an appropriate gap-fillingadhesive, secondary nailing is also required (in case of fire)
13mm plaster achieved in two coats (10mm + 3mm finish)
Because of the wall accuracy in Thin-Joint, a spray plaster (3-4mm) can be used, this can reduce the time taken.
Blockwork wetting:Relatively small areas at a time
Although traditionally tiling is applied to a wall which has got aplaster finish, they can be laid straight onto the blockwork, if thewall is plumb (Thin-Joint adv)
For areas of low aesthetic importance the blocks can be painted
40
External FinishesExternal Finishes
Types:Types:–RenderRender–TilesTiles–WeatherboardWeatherboard
•PreparationPreparation•SpecificationSpecification•ApplicationApplication
Again this slide really used as an overview for thefollowing one.
Preparation: Block surfaces should be clean of dust,loose particles or contamination before application offinish
41
Finishes - ExternalFinishes - External• Tile hanging or weather boardingTile hanging or weather boarding
– Vapour Vapour-permeable membrane should be used-permeable membrane should be used• RenderRender
– Mix to be 1:1:6 or 1:2:9 (C:L:S) Mix to be 1:1:6 or 1:2:9 (C:L:S)– Two coat render Two coat render
• base coat 10-12mm thickbase coat 10-12mm thick• finish coat 6-8mm thickfinish coat 6-8mm thick
– Joints should be recessed Joints should be recessed– Blockwork should be cleaned Blockwork should be cleaned– Blockwork may need to be wetted to balance Blockwork may need to be wetted to balance
the initial suction.the initial suction.–Thin coat spray render can be used forThin coat spray render can be used for
Thin-Joint wallsThin-Joint walls
Tile Hanging - Tiles should be hung on horizontalbattens, with membrane behind
Weatherboarding - Hung on vertical battens, withmembrane behind
Rendering - One of the most common finishes to see notperforming properly.(eg cracking). But can be done verysuccessfully - if you get proper advice from TechnicalServices Dept.
Thin coat render 3-4mm can be used on thin joint wallsbecause of greater accuracy of construction
42
FixingsFixings
•Fixing into aircrete blocks is simple andFixing into aircrete blocks is simple andeffectiveeffective
•Screws, plugs or nails as appropriateScrews, plugs or nails as appropriate
•Very secure and reliable fixingVery secure and reliable fixing
Lightweight fixtures: Light door frames, skirtings,linings. - proprietary nail fixing, cut nails - should bedriven to minimum depth of 50mm into blockwork.
Medium-weight: Heavier door frames, or battens andsmall fixtures - proprietary plugs and woodscrews arerecommended - screws should penetrate block to a min.depth of 25mm.(I.e 40mm from finished surface)
Heavier-weight items: Radiators and cupboards -proprietary plugs recommended - fixings should not becloser to the free edge of the block than the depth ofembedment.
43
FIXINGSFIXINGS
Helical nailHelical nail
Fisher GBFisher GB
Plug & ScrewPlug & Screw
Direct fixingDirect fixing
Turbo Turbo
AnchorAnchor
Diagrams to show example types of fixing:
Helical nail & Direct fixing for lightweight fixtures.
Plug & Screw, Anchor and Turbo fixing for medium-weight fixtures.
Fischer GB for heavy weight items.
44
Technical SupportTechnical Support
45
Technical TeamsTechnical Teams
•Technical Sales DivisionTechnical Sales Division
–Personal contact with specifying &Personal contact with specifying &
regulatory professionalsregulatory professionals
•Technical Services DepartmentTechnical Services Department
–Detail design and specification adviceDetail design and specification advice
•Research & DevelopmentResearch & Development
–Developing new products, techniquesDeveloping new products, techniques
and standards both home and abroadand standards both home and abroad
Technical Sales Dept:
Deals with specifying and regulatory professionals
Office and site visits made to develop construction solutions to meet theneeds of the designer
Assist ASAP with the brand and/or performance specification
Technical Services Dept:
Hotline for customers
Structural design advice
Advice on Meeting Building Ergs.
Energy calicos
All technical teams have a close association with industry groups i.e. DETR,BRE, BBA, BIAT, NHBC
R&D:
UKAS approved Lab
Product Development
Involved in developing Eurocodes, and Standards
46
The Communication ProcessThe Communication Process
Customer
Technical ServicesDepartment
Marketing
Research &Development
Technical SalesDivision
Visual to show the role of each department in communicatingwith the customer/potential customer.
Emphasis should also be placed on the internal communicationinvolved between departments.
Eg support literature for TSM’s, training, lead generation etc
R&D: there main communication process is with industrygroups/bodies. Info then passed on to other departments, whoinform customers.
47
Environmental IssuesEnvironmental Issues
•Main ingredient is PFA which is wasteMain ingredient is PFA which is wastefrom coal fired power stationsfrom coal fired power stations
•Less additional insulation is required whenLess additional insulation is required whenusing aircrete blocksusing aircrete blocks
•Aircrete blocks have the ability to storeAircrete blocks have the ability to storeheat (latent heat capacity)heat (latent heat capacity)–This heat is then radiated back into theThis heat is then radiated back into the
house when the temperature dropshouse when the temperature drops–Resulting in temperature stabilityResulting in temperature stability
Note to speaker: PFA is indeed the main ingredient across the company as awhole (I do appreciate that sand is used at Westbury)
Insulation materials are normally derived from mineralbased sources combined with man made resins or fromoil based resources. So the less you use the better!
The following is taken from the “Design & Performance ofTraditionally built houses” by Alan Tovey, for the THB.Resulting from a BRE report.
Latent Heat Capacity: Blocks absorb heat from theheating system and other incidental sources eg. Sunlight.
This heat is then radiated back into the property, helpingto maintain the temperature.
The thermal capacity also helps during the summer as itreduces the peak temperatures by 50C or so, thusproviding a more comfortable living environment.
48
SummarySummary
•Aircrete blocks are: Thermally efficient,Aircrete blocks are: Thermally efficient,strong, resistant to fire, frost and sulfatestrong, resistant to fire, frost and sulfateattackattack
•Celcon blocks provide a solution for manyCelcon blocks provide a solution for manyapplicationsapplications
•Aircrete can reduce the need for additionalAircrete can reduce the need for additionalinsulationinsulation
•Codes of Practice & Regulations can be foundCodes of Practice & Regulations can be foundin the Celcon Book of Blocks (Chapter 7)in the Celcon Book of Blocks (Chapter 7)
A Summary listing all the key issues covered in thepresentation.