GB2500744A

GB2500744A - A pliable building material

Info

Publication number: GB2500744A
Application number: GB1221107.4A
Authority: GB
Inventors: Keith Robert Southey; Joseph John Orsi
Original assignee: FIBRELIME Ltd
Current assignee: FIBRELIME Ltd
Priority date: 2011-11-24
Filing date: 2012-11-23
Publication date: 2013-10-02
Anticipated expiration: 2032-11-23
Also published as: GB2500744B; GB201221107D0; WO2013076503A1

Abstract

A pliable material for use in building is disclosed where the material comprises water and an aggregate of particle size less than 50 micron. Additionally, a binding agent is included comprising at least 70% calcium hydroxide. Further, fibres are included to give additional advantageous properties. The fibres can be formed of non-biological material such as polypropylene, or coated with a non-biological material and be of a length of from 2 150 mm. Aggregate can be selected from chalk, marble, limestone, calcium silicate or sand and can additionally include or consist of pumice, expanded clay perlite or silica glass.

Description

BUILDING MATERIAL

Field of the Invention

The invention reLates to buiLding materiaLs, in particuLar Lime-based buiLding materiaLs.

Background to the Invention

A number of different pLiabLe buiLding materiaLs are used to form specific buiLding features once they have hardened, such as pLasters/renders, screeds, fLooring, foundations, mortars, grouts and the Like. Lime-based buiLding materiaLs have substantiaL sustainabLe credentiaLs when compared with, for exampLe, gypsum-or cement-based materiaLs; they are for exampLe readiLy recycLabLe and biodegradabLe and absorb carbon dioxide during the setting process (especiaLLy for non-hydrauLic products). Carbon emissions and energy consumption during the production of Lime-based products is aLso reLativeLy modest. Furthermore, Lime-based materiaLs provide great visuaL appeaL and are seLf-heaLing and breathabLe (i.e. water permeabLe, so that moisture can be absorbed and Eater reLeased). Despite this, the characteristics of prior Lime-based materiaLs have meant that their use for particuLar features and in particuLar buiLding types has been Limited (e.g. to pLasters for traditionaL buiLdings), as wILL be described beLow.

When empLoyed as a pLaster/render, Lime-based products have a number of Limitations. For exampLe, their adherence to a variety of common buiLding materiaL substrates is modest or poor, particuLarLy for light-weight bLocks, pLasterboard, pLy board, fireboard, gLass, metaLs, some insuLation materiaLs, pLastics products etc., making them unsuitabLe for some historic buiLding work but in particuLar for new buiLd work. In addition, variation of substrate, for exampLe in a waLL where masonry, daub, Lath, reed, timber and other buiLding materiaLs can occur in a singLe area to be pLastered, can Lead to cracking at the interface or junctions. It is aLso difficult to buiLd up the Lime pLasters to the desired thickness, by appLying one or muLtipLe coats, due to deLamination from the substrate or shearing between coats.

Shrinkage and cracking are aLso probLems, on both mixed and singLe substrate materiaLs.

To reduce these problems, reinforcement can be added in the form of naturaL fibres, such as hair (e.g. horse, goat or pig hair), straw, reed fibres, hemp and the Like, though such bioLogicaL materiaLs degrade over reLativeLy short timescates, especiaLLy on externaL areas which get wet. Synthetic fibres (e.g. poLypropyLene, gLass and asbestos) that are resistant to such degradation have aLso been used but such fibres have a tendency to push through the pLaster surface Leaving a bristle finish that is often unacceptabLe to the user. In addition, the resuLtant materiaLs show Limitations in their generaL performance (e.g. poor or modest adherence, impact resistance, etc).

Lime pLasters require speciaList knowLedge and skiLLs to appLy them. For exampLe, the setting of e.g. non-hydrauLic Lime pLaster requires carbonation, which needs to be controLLed to achieve a reLiabLe set. This in turn requires fairLy arduous pre-and after-care in the form of damping down with water.

FinaLLy, Lime-based buiLding materiaLs have a reLativeLy Low impact resistance, making them LargeLy unsuitabLe for Load-beaiing surfaces or indeed as Load-bearing structuraL eLements in themseLves. They aLso have reLativeLy modest structuraL fLexibiLity, tensiLe strength, and resistance to fire and freeze/thaw cycLes.

It is an object of the present invention to provide a soLution to these probLems.

Summary of the Invention

In a first aspect of the invention there is provided a pliable material for use in building, said materiaL comprising; water, an aggregate of particle Less than SOp, a binding agent comprising at Least 70% calcium hydroxide, and a plurality of fibres, preferably of non-biological origin or coated with a coating of non-biological origin.

Preferably, the aggregate is selected from chalk, marble, limestone, calcium silicate or sand or mixture thereof. Alternatively or additionally, the aggregate can include1 or be entirely of: pumice, expanded clay perlite or expanded silica glass in order to improve insulation.

Conveniently, the binder includes a clay, linseed oil or casein to provide the pliable material with improved breathing.

The fibres are conveniently of a non-biological origin or natural fibres coated with a material of non biological origin, and especially conveniently selected from polypropylene (PP), PMF, alkaline resistant glass fibre, cellulose or casein.

The fibre lengths in the first aspect are preferably from 2-150mm in length, especially preferred in 2-40mm and particularly preferred from 2-18mm in length.

The width of the fibres in the first aspect is conveniently from 2 -7Op.

The fibre can be present at an amount up to 20 kgm3. However, the fibre is preferably present in the material in an amount of from 2-4 kg per cubic metre, 2.1 -4.0 and further preferably 3.0 -4.0.

In a second aspect, the invention provides a pLiabLe buiLding materiaL comprising: water; an aggregate; a binding agent, comprising at Least 70% caLcium hydroxide; and a pLuraLity of fibres of non-bioLogicaL origin each having a maximum diameter of <5Opm.

In preferred embodiments each of said fibres has a maximum diameter of 48pm.

In preferred embodiments said fibres comprise a pLastics materiaL, preferabLy poLypropyLene or aLkaLine resistant fibregLass fibres, and/or said fibres are coated with a surfactant.

In preferred embodiments the pLiabLe buiLding material further comprises an insuLation materiaL and/or a non-binding materiaL that produces a pozzoLanic effect. PreferabLy, said aggregate and/or said insuLation materiaL comprises perLite or pumice.

ALso provided is a substantiaLly soLid buiLding materiaL formed by the setting of the pLiabLe buiLding materiaL set out above, together with a paneL for a buiLding comprising said substantiaLly soLid buiLding materiaL, a structuraL eLement for a buiLding comprising said substantiaLly soLid buiLding materiaL, and a fLoor, waLL, door or ceiling of a buiLding to which said substantiaLly soLid buiLding materiaL has been appLied.

The invention additionaLLy provides the use of said substantiaLLy soLid buiLding materiaL as a pLaster or render for a waLL, door or ceiLing, as a masonry mortar or grout, as an adhesive, fire retardant or thermaL insuLation materiaL, as a screed for a fLoor, or as a structuraL eLement for a buiLding.

Further provided is a composition suitabLe for the manufacture of the pLiabLe buiLding materiaL of the invention, said composition comprising said binding agent and said pLuraLity of fibres. In one aspect, said composition is substantiaLLy free of water. In preferred embodiments of that aspect, the composition additionaLLy comprises the foLLowing components of the pLiable buiLding materiaL: the aggregate and/or the insulation materiaL and/or the non-binding materiaL that produces a pozzolanic effect.

In an aLternative aspect, said composition comprises water.

ALso within the scope of the invention is a pliable building material substantially as described herein, a substantiaLly solid building material substantialLy as described herein, and a composition suitable for the manufacture of a pliable building materiaL, said composition substantially as described herein.

Detailed description of Preferred Embodiments

The invention relates to a pliable building material, such as a material that can for example be poured, moulded, spread or sprayed. The material of the invention is a lime-based building material i.e. one where the binding agent comprises at least 70% calcium hydroxide.

In a series of results relating to a first aspect of the invention, the improvements to the quaLity of pLaster produced using an aggregate of particle size <5Opm is shown. These further results are set out in the folLowing Tables 1 -17. Without being Limited to theory, it is believed that the smalLer the particle size of the aggregate, the better the performance due to the adherent properties of the composition increasing. In addition, there is a reduced chance of water accumulating into large droplets which can cause damage when under freezing conditions due to their expansion: an effect known as freeze spalLing.

The test methods used correspond to those used in the results described earLier, and the assessment scores achieved on these tests also correspond.

In the first aspect of the invention, the reduced particle size of the aggregate allows fibres of larger diameter to be used compared to those of other aspects. The preferabLe range for said diameter is therefore from 5 -7Opm when used with a reduced particle size aggregate.

In a stiLL further aspect of the invention it is also found advantageous to utiLise fibres of mixed Length, for exampLe 12mm with 18mm. However fibres of mixed Length varying typicaLLy from 2 -40mm, have been shown to be effective and it is expected that Lengths of up to 150mm can be utiLised. Where required, fibres of Length greater than 40mm have been shown to be effective. When a composition is for use as a skim then shorter fibres down to 2mm can be used, whereas an appLication requires a thick one-coat then Longer fibres up to 40mm are suitabLe.

In generaL a greater amount of fibres in a mix tends to confer improved properties aLthough where pLaster has to be remixed after storage to improve pLaster workabiLity, then the greater amount wouLd be disadvantageous.

The use of mixed fibre Lengths enabLes the use of aggregate which incLudes Large particLes, especiaLLy up to 5mm and in some embodiments up to 10mm. This effect is enhanced when higher quantities of fibres are used. In particuLar, a concentration of greater than 2kgm3of mixed fibres has been found to enabLe Larger size aggregates to be empLoyed.

In both aspects of the invention, the thermaL insuLation properties can be improved by adding materiaLs such as perLite or pumice.

The compositions tested are detaiLed in TabLe 1. As with the compositions indicated in ExampLe 1, the amount of water in the mixed composition can vary. The composition [CE-FE is as per that shown in ExampLe 1.

TabLe 1

Plaster mix: Abrev. Content Synthetic fibre Synthetic Fibre Binder ParticLe size Length weight _________________ CC 100-62 C. carbonate! 6mm 2kg/ms C. Hydroxide chaLk 100pm powder + water down CC5O-62 C. carbonate! 6mm 2kg/me C. Hydroxide chalk 5Opm powder + water down CC5O-M2 C. carbonate! Mixed 2kg/me C. Hydroxide chalk 5Opm powder + water down LFC EF C. carbonate! 18mm 4kg/m C. Hydroxide *i-chalk SOpm water down CC5O C. carbonate! Mixed 4kg/ms C. Hydroxide + chalk SOpm water down CSSO C. carbonate! Mixed 4kg/ms C. Hydroxide + stone of 50 pm water down CCS C. carbonate! Mixed 4kg/me C. Hydroxide + chalk of 5mm water down CSS C. carbonate! Mixed 4kg/ms C. Hydroxide + stone of 5mm water down M4 None Mixed 4kg/ms C. Hydroxide powder + water PUM pumk crS ItS 4kgm C<4$dr4de + I ate PE PeSte MS 4km C, Fhjdmo de + siaLfjo s]eiJalPw sJaLpoJ aLp q!M paJedwo) sao paqi]qiq pedwi u!puesLpiM ap ueLp pedwi ap LpIM paJedwo) sapo uieJls 8un2aJq aLp U2L aqixaj JOj spajap MJ UI siaqio aLp U2Lfl iaieai Apu2Diiu2is 8UDp2JD aDeiJalul aLp LpIM paJeduJo JaeaJ ApueijiuThs aow /c]1u2DiJiuis LpIM paAoJdwi pue apaq icpueijiuThs 2 U2SLIM ssa Apueijiuis auaaqpe JaeaJ e peq s]eiJa;ew aie s]eiJalew dJ_Jdl Aq paqeua wojad s]eiJaew ue s]eiJaew MOL]5 s]eiJalew icpueijiuis MOLS paL]ThqiH pai]qThH! 1J0M WDIS paL]ThqiH pa1Ll!H Paq2!1qHj paq]L!q sase J UO!Sfl]DUO) _______________ _______________ _______________ _______________ _______________ _______________I]__________ -__________ __________ __________ __________ __________ kfld _____________________ __________ S k __________ _______ F 9 0 FE 55) E6L E0 F? ES 09 FE SD) El EL 0? ifOil 8L j79 F? 8E F? LLLE F ?N05)) FV8 L EL FL EEEV F? ?9-OS)) LSEL L L L EESL EL ?9-OOL)) saaaa a]BJS S-L 8)1 SIP-i JO ON WW aies S-L:pJnsPN q2uans oisuai so Aiiqixa JOM weis sa wJoJ-aJd jso pcdw)BJD aepau sa auaJaipy F I I seqo[ J I I speww seio aq 2UiJBeqS 2UU1S aip o pai2dwoJ I I I jesed eipo ei ip!M SBJ.TUOD U! eew2p JO SU!S JO S1JIS eDueJeedde I I I qT!M paJedwoJ sso;eeq 4nOq4iM sain;ejadwa; ou paoqs ou JO ieuu!w p945!UIJ paAoJdwi I I peAoJdwl MO] pUBslfl!M s]eIJaew peoqs s1e!JeWW eeq s]BIJa4BLU seueejp U2J14!UThS °N UBJ!JiU!S 0N)J PUB VJfld UBJ S]21J242W pBTi]Th]l]ThH pBi]Th]l]ThH Pa1I8!]4!H pa;q!]q8!L1 41 [;UeJJUs 0N j:uolsnpuo) ___ ___ 79? ____ ___ ___ ____ __ __ I I £9? -----Nfld _____________ I g' -s auauaavj i7V1 --LE V LSL V [ 7SL SSJ --Si? 7 6 7 Ed. 533 asu --na /1' S U 8Th dtDii ---£2 £ S V 9LL ?N-OS33 ---? LL £OL 9E 9SL ?9-OSJD LEZ £86 8L? ? L LS9 £5 ?VL ?9-OOLJJ SJflOH SJflOH apeJ2ua3 aes 5-k aes 5-k WW 312DS S-k S3flU1N:painseaN z s; i. is aDueieadde aDue4sisaj 1!!qeawJad 1!!qeawJad auessaJ ewaqj;sa Melfl-azeaJj;sa; ieaqs DBJD &e)u!Jq5 aJJ qaqe Adherence Test

Table 3

Ambient Temp: 17°C SampLe size (over substrate): lOOxlOOx8mm Test sampLe PLaster-board Scratched glass Dry block Mean score CC100-62 2 1 1 1.33 Cc50-62 3 2 2 2.33 CC5O-M2 3 3 3 3 LFC-FF 5 3 5 4.33 CCSO 5 4 5 4.67 CSSO 5 4 5 4.67 CC5 3 3 4 3.33 CS5 3 3 4 3.33 M4 5 4 5 4.67

In concLusion -

LFC-FFCC5O, C550 and M4 has significantLy greater adherence compared with the other pLaster materiaLs (generaLLy), and shows a substantiaL and reLiabLe adherence to a number of substrates that previousLy couLd not be effectiveLy pLastered/rendered using a Lime-based product, such as dry bLocks, gLass and construction board.

Interface Crack Test

Table 4

Ambient Temp: 17°C SampLe size: 700x250x3-l2mm Test sample 1 2 3 Total score Mean score CC100-62 780 815 665 2260 753.33 CCSO-62 440 410 450 1300 433.33 Cc50-M2 320 490 305 1115 371.67 LFC-FF 20 0 40 60 20 CC5O 15 3 16 34 1133 CS5O 14 18 6 38 12.67 CC5 55 85 40 180 60 CSS 45 15 60 120 40 M4 5 12 19 36 12

In concLusion:

[C-FE, CC5O, CS5O and M4 shows significantLy Less interface cracking compared with the other pLaster materials.

Impact test

Table 5

Ambient Temp: 17°C SampLe size: 75x65x6mm Test sampLe 1 2 3 TotaL score Mean score CC100-62 1 1 1 3 1 Cc50-62 2 2 1 5 1.67 CC5O-M2 2 2 3 7 2.33 LFC-FF 8 7 7 22 7.33 CCSO 9 8 7 24 8 CSSO 8 7 10 25 8.33 CC5 5 5 7 17 5.67 CS5 6 5 7 18 6 M4 8 10 8 26 &67

In concLusion:

[K-FE, CCS0J CS5O and M4 can withstand a significantLy greater impact than the other materiaLs.

Pre-form test

Table 6

Ambient Temp: 17°C SampLe size: 500xlSOxl2mm Test sample 1 2 3 Total score Mean score CC100-62 1 1 1 3 1 CCSO-62 2 1 1 4 1.33 C5O-M2 4 3 4.5 11.5 3.83 LFC-FF 7.5 8 6.5 22 7.33 CC5O 7.5 10 8.5 26 &67 CS5O 10.5 7 8 25.5 8.5 CCS 5 5 4.5 143 4.83 CSS 4.5 6 4 14.5 4.83 M4 9 8.5 9 26.5 8.83

In concLusion:

[CE-FE, CCSOJ CS5O and M4 performs significantLy better than the other materiats in withstanding faiLure under defLection.

Skim work

Table 7

Ambient Temp: 19°C SampLe size: 75x440x2-3mm Test sampLe 1 2 3 TotaL score Mean score CC100-62 1 1 1 3 1 CC5O-62 1 1 1 3 1 CcSO-M2 3 2 3 8 2.67 LFC-FF 4 4 4 12 4 CCSO 5 5 5 15 5 CSSO 5 5 4 14 4.67 CC5 3 3 2 8 2.67 CS5 3 3 3 9 3 M4 4 5 5 14 4.67

In concLusion:

[C-FE, CC5OI CS5O and M4 have significantLy improved properties in respect of skim work.

FLexibiLity Test

Table 8

Ambient Temp: 19°C SampLe size: l8Ox6Ox4mm Test sampLe 1 2 3 TotaL score Mean score CC100-62 122 160 125 407 135.67 CC5O-62 89 90 75 254 84.67 CCSO-M2 /0 /2 50 192 64 LFC-FF 18 19 17 54 18 CCSO 15 20 15 50 16.67 CSSO 16 17 17 50 16.67 CC5 37 52 32 121 40.33 CS5 45 48 30 123 41 M4 15 15 14 44 14.67

In concLusion:

LFC-FF, CC5O, CS5O and M4 are significantLy more flexibLe than the other materiaLs.

Tensile Strength Test

Table 9

Ambient Temp: 17°C SampLe size: l3OxlOOxl2mm Test sampLe 1 2 3 TotaL score Mean score CC100-62 2 2 3.5 7.5 2.5 CC5O-62 3 1.5 2.5 7 2.33 CCSO-M2 / 6.5 10 23.5 7.83 LFC-FF 19.5 22.5 25 67 22.33 CCSO 22.5 25 25.5 73 24.33 CSSO 21 19 18 58 1933 CC5 21 22.5 28.5 79 19.33 CS5 21 21 23 65 21.67 M4 20 22.5 19 615 205

In concLusion:

[K-FE, CCSOJ CS5O, CC5, CS5 and M4 had a significantty greater breaking strain compared with the other materiaLs.

Fire Resistance Test

Table 10

Ambient Temp: 17°C Test sample 1 2 3 Total score Mean score CC100-62 15.25 1525 12 42.5 14.17 CCSO-62 16 18.45 12.45 46.9 15.63 CC5O-M2 13.75 19.15 20 52.9 17.63 LFC-FF 14.75 13.15 16.15 44.05 14.68 CC5O 22.5 15.45 18.4 56.35 18.78 CS5O 18 19.5 13.75 51.25 17.08 CC5 19.15 15 19 53.15 17.72 CSS 16.4 13.7 16 46.1 15.37 M4 13.8 18.8 16.7 49.3 16.43 The pLasters tested show significantLy simiLar fire resistance.

Finished Appearance Test

TabLe 11

Ambient Temp: 19°C SampLe size: 390x680x20mm Test sample 1 2 3 TotaL score Mean score CC100-62 3 4 3 10 3.33 CC5O-62 4 3 4 11 3.67 CCSO-M2 4 4 4 12 4 LFC-FF 4 5 5 14 4.67 CCSO 5 5 5 15 5 CSSO 5 5 4 14 4.67 CC5 5 3 4 12 4 CS5 4 4 4 12 4 M4 5 5 5 15 5 The finished appearance of aLL pLasters gave a good or exceLLent finished appearance with few or no defects.

Shrinkage Crack Test

TabLe 12

Ambient Temp: 19°C SampLe size: 390x680x20mm Test sampLe 1 2 3 TotaL score Mean score CC100-62 60 95 42 197 65.67 CC5O-62 85 81 45 211 70.33 CCSO-M2 10 0 5 15 5 LFC-FF 0 0 0 0 0 CCSO 0 0 0 0 0 CSSO 2 0 0 2 0.67 CC5 5 2 20 27 9 CS5 35 0 12 47 15.67 M4 0 0 0 0 0 [C-FE, CC5O-M2, CC5O, C550, CC5 and M4 showed no or minimaL signs of shrinkage, in contrast to the other pLaster materiaLs.

Shear test

Table 13

Ambient Temp: 19°C SampLe size: 440x215x75mm Test sample 1 2 3 Total score Mean score CC100-62 1 1 1 3 1 Cc50-62 1 2 2 5 1.7 Cc50-M2 3 3 3 9 3 LFC-FF 5 5 5 15 5 CC5O 5 5 5 15 5 CS5O S 5 5 15 5 CC5 4 4 4 12 4 CSS 4 3 5 12 4 M4 5 5 5 15 5 [K-FE, CCSOJ CS5O and M4 showed no signs of shearing compared with the other pLaster materiaLs.

Freeze-thaw Test

TabLe 14

Ambient Temp: 20°C SampLe size: 70x24x12mm Test sampLe 1 2 3 TotaL score Mean score CC100-62 2 2 2 6 2 CC5O-62 2 2 2 6 2 CcSO-M2 3 2 2 7 2.33 LFC-FF 5 5 4 14 4.67 CCSO 5 5 5 15 5 CSSO 5 5 5 15 5 CC5 4 3 4 11 3.67 CS5 3 5 3 11 3.67 M4 5 5 5 15 5 CC5O, CS5O and M4 can withstand Low temperatures without significant damage, in contrast with the other pLaster materiaLs Thermal Resistance Test

TabLe 15

Ambient Temp: 21°C SampLe size: 240x140x12mm Test sampLe 1 2 3 Total score Mean score CC1Oc.H6a***H I I I I 78HH H H Z7$:HHHH H HH 83 4H HH HH 278H LFC-FF 27.5 27.5 27.4 82.4 27.47 CC5O 27.5 27.4 27.4 82.3 27.43 CSSO 27.5 27.5 27.5 82.5 27.5 M4 27.4 27.4 27.5 82.3 27.43 PUM 26.7 26.7 26.6 80 26.67 PER 26.4 26.4 26.4 79.2 26.4 PB 28 28 28 84 28 PS 25.5 25.5 25.5 76.5 25.5 PB = pLasterboard Ps = poLystyrene [C-FE improves on CC100-62. There are no significant differences between LEC-FE and other pLasters, however the addition of pumice or pertite in PUM and PER further improved the thermaL resistance of pLaster materiaLs.

PermeabiLity test 1

TabLe 16

Ambient Temp: 19°C SampLe size: 330x330x330x20mm box Test sample 1 2 3 TotaL score Mean score *CC1OO-62. . ::. . ::. .*** . .y. :.: . :9333 LEC-EF 103 96 96 295 98.33 CC5O 99 97 97 293 97.67 There was no significant difference in permeability between pLaster materiaLs.

PermeabiLity test 2

TabLe 17

bOg sampLes had 35g (3SmL) water added to them and pLaced in a room at 30°C. The time taken for the sampLes to return to a mass of bOg was measured (hours): Ambient Temp: 30°C SampLe size: 95x65x12mm Test sampLe 1 2 3 TotaL score Mean score CCIOO-GtHH HH H HH HH H 24H1 HH 241 I flH I I flSIHHHH H LFC-FF 23 23 23 69 23.00 CCSO 23 23 24 70 23.33 There was no significant difference in permeability pLaster materiaLs.

The binding agent, in the presence of water, binds together (with adhesive action) the components of the pLiable buiLding materiaL. In the materiaL of the invention at [east 70% of the binding agent is caLcium hydroxide (aLso known as "sLaked Lime or hydrated Lime), in contrast to e.g. cement-based or gypsum-based materiaLs where the binding agent comprises a majority of caLcium siLicates and caLcium sutphates, respectiveLy.

The Lime-based binding agent can be adapted such that it is non-hydrauLic i.e. that the buiLding materiaL comprising it sets primariLy or soLeLy via the process of carbonation (i.e. reaction with atmospheric carbon dioxide). In such instance if the buiLding materiaL itseLf is to be non-hydrauLic then no non-binding materiaL that produces a pozzolanic effect shouLd be further incLuded in the materiaL. A non-hydrauLic Lime-based binding agent wiLL preferabLy comprise at Least 95% caLcium hydroxide, more preferabLy at least 99% caLcium hydroxide, and most preferabLy wILL consist of essentiaLLy pure caLcium hydroxide. A non-hydrauLic buiLding materiaL of the invention is advantageous because it can be stored for extended periods of time without setting (using appropriate storage conditions i.e. those that Limit the access of the materiaL to carbon dioxide).

AlternativeLy, the Lime-based binding agent can be adapted such that it is hydraulic i.e. that the buiLding materiaL comprising it can sets via reaction with the water in the building materiaL. In such instance the hydrauLic nature of building materiaL itseLf can be increased by further incLuding in the materiaL a non-binding materiaL that produces a pozzoLanic effect. A hydraulic Lime-based binding agent wiLl preferably comprise at least 5%, more preferably at Least 10% (and up to 30%) of other minerals that confer hydraulic nature, preferably siLicates (deriving e.g. from cLay and siLica). A hydrauLic buiLding materiaL of the invention is advantageous because it enabLes reLativeLy thick layers/structures of the materiaL to set in wet environments, especiaLLy under water or very wet conditions where setting via carbonation is too slow or not possibLe.

The aggregate of the pLiabLe buiLding materiaL of the invention is the component that constitutes the voLuminous buLk and structural strength of the materiaL. The aggregate can be chosen from e.g. sand, perLite, pumice, gypsum, expanded gLass, vermicuLite and crushed (or powdered) stone or chalk. ChaLk or stone, especiaLly powdered chaLk, is a preferred materiaL because of its general performance within the buiLding material (as shown by the ExampLes). PerLite is another preferred materiaL because it can, in addition, provide insuLation, increased hydrophobicity and increased freeze/thaw resistance.

In a second aspect, the invention provides a pLiabLe buiLding material comprising: water; an aggregate; a binding agent, comprising at Least 70% calcium hydroxide; and a pLuraLity of fibres of non-bioLogicaL origin or coated with a material of non-biological origin each having a maximum diameter of c5Opm.

The pliable buiLding materiaL of the second aspect of the invention also comprises a pLuraLity of fibres of non-bioLogical origin each having a maximum diameter of csopm (and in preferred embodiments no other fibre materiaL is incLuded in the buiLding materiaL).

Each of said fibres can be any substantiaLLy eLongate structure provided that its Largest cross-sectionaL distance is c5Opm, preferably 148pm, preferabLy 45pm, preferabLy 40pm, more preferabLy 30pm (and wherein its smaLlest cross-sectional distance is preferably ?5pm, more preferabLy ?lOpm). In preferred embodiments each of said fibres has a substantiaLLy uniform cross-section, and preferabLy said cross-section is substantiaLly circuLar. PreferabLy, the Length of each fibre is between 2mm and 150mm, more preferabLy between 5mm and 50mm, moie preferabLy between 5mm and 40mm most preferabLy between 8mm and 28mm.

Each of the said fibres for use with both aspects of the invention is of non-bioLogicaL origin or has a coating of non-bioLogicaL origin, i.e. has not been synthesized by a biologicaL organism and is not a biopoLymer (a poLymer that can be synthesized by an organism and incLuding nucLeic acids, poLypeptides, potysaccharides and Lipids). The use of aLternative, so-caLLed synthetic fibres avoids the probLem of degradation of the fibre (either in a stored wet mix or in the set materiaL itseLf).

It has surprisingLy been found that the use of said pLuraLity of fibres in the buiLding materiaL of the invention provides at Least one of the foLLowing (in reLation to the pLiabLe buiLding materiaL and/or a substantiaLLy soLid buiLding materiaL formed by the setting of said pLiabLe buiLding materiaL, as appropriate): -increased adherence to many different buiLding substrates, incLuding a substantiaL and reLiabLe adherence to a number of substrates that previousLy couLd not be effectiveLy pLastered/rendered using a Lime-based product, such as dry bLocks and construction board (enabling the use of Lime-based pLasters in the new buiLd environment) -reduced cracking at junctions/interfaces of mixed-materiaL substrates, increasing the versatiLity of the materiaL (especiaLLy in the traditionaL buiLd environment).

-improved impact resistance, enabLing the use of Lime-based buiLding materiaLs for Load-bearing finishes or structures -skim work is enabLed; this in turn enabLes quick and efficient repair of (and thus conservation of) worn or damaged waLLs and ceiLings.

-increased structuraL fLexibiLity; this enables the materiaL to yieLd better to thermaL changes and to structuraL movement of buiLding fabric, which is particularLy usefuL in historic buiLdings without foundations.

-increased tensile strength; this reduces the breakage of plaster keys and helps to prevent the cracking of the set materiaL when dimensional changes pull against its width.

-improved fire resistance -improved surface appearance (the fibres do not breach the surface of the material) -decreased shrinkage and perimeter cracking and shearing -improved freeze/thaw resistance -improved thermal insulation Furthermore, the skill and time required to apply the pliable building material of the invention is decreased, whilst the need for pre-and after-care (and corresponding volume of water for damping down) is reduced (in turn reducing labour and water costs).

In addition, the building material of the invention retains a number of properties of prior limed-based and synthetic fibre-containing building materials, such as: -permeability/breathabiLity of the material -substantial longevity of the fibre and hence of the pliabLe (e.g. stored) buiLding material and the set product itself -the ability to be pumped or sprayed In preferred embodiments the fibres comprise a plastics material, preferably poLypropylene.

An additional advantage of using polypropylene is that this particular plastics material is readiLy recycLed. AlternativeLy, the fibres comprise carbon fibres or glass fibres. OptionalLy the fibres are not metaLlic.

In preferred embodiments the fibres are coated (partiaLLy or fuLLy) with a surfactant; in particuLar this assists with the dispersion of the fibres within the buiLding materiaL.

In preferred embodiments, the fibres constitute at Least 0.0 1% of the mass of the pLiabLe buiLding materiaL, preferabLy at Least 0.02%, more preferabLy at Least 0.1%, and more preferabLy at Least 0.2%.

A number of additionaL components can be added for a range of purposes. For exampLe, in preferred embodiments the pLiabLe buiLding materiaL further comprises an insuLation materiaL (i.e. a materiaL that can reduce the rate of heat transfer through the materiaL).

Such materiaL couLd be for exampLe hemp, pertite, pumice, vermicuLite, expanded cLay or expanded gLass. ALternativeLy (or in addition) the pLiabLe buiLding materiaL further comprises a non-binding materiaL that produces a pozzoLanic effect (i.e. a material that can be considered not to be used within the binding agent but as an additionaL, pozzoLan component), such as fLy ash. Such materiaL increases the hydrauLic set of the pLiabLe buiLding materiaL and typicalLy increases the compressive strength of the set materiaL.

Set products The invention aLso provides a substantiaLLy (or compLeteLy) soLid buiLding material formed by the setting of the pLiabLe buiLding materiaL of the invention. As described above, this setting might require carbonation (for non-hydrauLic materiaL) or might occur under water (for hydrauLic materiaL).

The invention thus further provides a paneL for a buiLding (e.g. suitabLe for constructing or covering waLLs and ceiLings, such as a waLLboard [further e.g. as a fireboard]) comprising said substantiaLly soLid buiLding materiaL. ALso provided is a structuraL eLement for a buiLding (such as structures made in situ such as a foundation or fLoor, or portabLe structures such as LinteLs) comprising (or consisting of) said substantiaLLy soLid buiLding materiaL. Further provided is a fLoor, waLL, door or ceiLing of a buiLding to which the substantiaLLy soLid buiLding materiaL of the invention has been appLied.

The invention provides the use of the substantiaLLy soLid buiLding materiaL of the invention as a pLaster or render for a waLL (internaL or externaL), door or ceiLing, where the substance can act as a finishing materiaL or a base for a finishing material, an insuLating material, a waterproofing materiaL and/or fireproofing materiaL. The substantiaLLy soLid buiLding materiaL of the invention can also be specificalLy used as a fireproofing materiaL (where the materiaL reduces the transfer of fire between two spaces and/or reduces the adverse effects of fire on an underLying materiaL) or thermaL insuLation materiaL (where the materiaL reduces heat transfer between two regions separated by the material).

The substantiaLLy soLid buiLding materiaL of the invention can further be used as a masonry mortar or grout, as an adhesive, as a screed for a fLoor, or as a structuraL eLement for a buiLding.

The invention further provides the use of a pLurality of fibres of non-bioLogicaL origin, each having a maximum diameter of c5Opm, to have any one, any combination, or aLL of the foLLowing effects on a lime-based buiLding materiaL: -to increase adherence to a substrate (especiaLLy a waLl or ceiLing substrate), in particuLar to a plasterboard, fireboard, pLyboard, foiL-faced PIR insuLation, scratched gLass, metaL (e.g. aluminium), dry brick, dry bLock and/or adobe -to reduce cracking at a junction/interface of a mixed-material substrate -to increase impact resistance -to enabLe skimming -to increase structuraL fLexibiLity -to increase tensiLe strength -to improve fire resistance -to improve surface appearance (e.g. to provide a finish whereby the fibres do not breach the surface of the material) -to decrease shrinkage and/or perimeter cracking and/or shearing -to improve freeze/thaw resistance -to improve thermal insulation -to reduce the skill and/or time required to apply -to reduce the need for or amount of pre-and after-care (and/or corresponding voLume of water for damping down) Precursor Products The invention also provides a composition suitable for the manufacture of the pliable building material of the invention, said composition comprising said binding agent and said plurality of fibres. Such a composition offers a relativeLy Lightweight and less bulky product that can be more efficiently stored and transported and provided to a user who can then add standard components as necessary to complete the buiLding material (e.g. an aggregate of choice). In an aspect of this composition of the invention, said composition is substantialLy free of water. This aspect is preferred if the composition provides a hydraulic set -otherwise water in the composition wouLd immediately initiate a setting process (irrespective of carbonation), reducing the potential for storage of the composition. In preferred embodiments of this aspect of the invention, said composition additionaLly comprises the folLowing components of the pliable building material: the aggregate and/or the insulation material and/or the non-binding materiaL that produces a pozzolanic effect.

To form the pliable building material of the invention the user then simply needs to add an appropriate amount of water (and any further required components) and mix.

In an aLternative aspect of the composition of the invention, said composition comprises water (and is e.g. in the form of a paste). This aspect can be chosen if the composition provides a non-hydrauLic set -the composition can be stored in wet' form without setting provided that access of the materiaL to carbon dioxide is Limited. To form the pLiabLe buiLding materiaL of the invention the user then simpLy needs to add an aggregate, and any required insuLation and/or non-binding materiaL that produces a pozzoLanic effect, and mix.

To manufacture this aspect of the invention, a dry mix (i.e. substantiaLLy free of water) comprising the binding agent and the fibres can be mixed with water. ALternativeLy, a soLution comprising the fibres (e.g. in suspension) can be formed, and then mixed with the binding agent (which can be provided e.g. in dry form or as a water-comprising form e.g. a Lime putty).

The folLowing exampLes exempLify the second aspect of the invention.

ExampLes

ExampLe 1 -preparation of buiLding materiaL and of comparator materiaLs.

ExampLe buiLding materiaL of the invention -LEC-FE Composition: lx 15L gauge of water 1 X 15L gauge of Lime putty [L] 3 X 15L gauge fine (powdered) chaLk [EC] (c5Opm) bog of poLypropyLene monofiLament fibres (PPME) at 18mm Length and 22 micron diameter, coated in surfactant [FE] The fibres were mixed with the water untiL evenLy dispersed. The Lime putty was then added and mixed into an even consistency. With further mixing the fine chaLk (an aggregate) was finaLLy added.

Comparator buiLding material -LCC-H * Crushed chaLk [CC] was used instead of FC * 200g goat hair [H] was used instead of FE Preparation as per LEC-FE, except that the hair was added Last in the mixing process.

Comparator buiLding material -LEC-H * 200g goat hair [H] was used instead of FE Preparation as per LEC-EF, except that the hair was added Last in the mixing process.

Comparator buiLding material -LEC-CF * lUOg coarse fibre [CE] -poLypropyLene fibriLLated fibres at 20mm Length and 50 micron diameter, coated in surfactant -was used instead of FE Preparation as per LEC-FE.

ExampLe 2 -summary of resuLts from experiments of ExampLes 3 to 24.

NB -PP = poLypropyLene Test Measurement LFC-LCC-H LFC-H LFC-CF Conclusion

FF

Adherence test 1-5 scale 4.1 2.0 2.4 2.9 LFC-FF has significantly greater adherence compared with the other materiaLs Interface crack mm 20.0 493.3 285.0 60.0 LFC-FF shows test significantly Less interface cracking compared with the other materiaLs Impact test No. of hits 7.3 1.0 1.3 3.0 LFC-FF can withstand a significantly greater impact than the other materiaLs Pre-form test Kg 7.3 1.8 2.2 1.3 LFC-FF performs significantly better than the other materiaLs in ________________ ________________ _______ ________ ________ ________ withstanding impact Skim work 1-5 scale 4.0 1.0 1.0 2.3 Skim work is enabLed ______________ ______________ ______ _______ _______ _______ by LFC-FF FLexibiLity test Degrees 18.0 69.3 71.0 44.7 LFC-FF is significantly more fLexible than the other materiaLs TensiLe Kg 22.3 1.8 2.7 5.3 LFC-FF had a strength test significantly greater breaking strain compared with the other materiaLs Fire resistance Minutes 14.7 5.3 5.2 1.3 LFC-FF is test significantly more resistant to a fLame than the other materiaLs Finished 1-5 scale 5.0 3.0 2.7 1.0 The finished appearance appearance of LFC-test FF is significantLy better than the other materiaLs Shrinkage crack mm 0.0 218.7 168.3 46.7 LFC-FF showed no test signs of shrinkage, in contrast to the other materiaLs Perimeter test mm 513.3 1773.3 1558.3 1233.3 SignificantLy less perimeter shrinkage in LFC-FF when compared with the other materiaLs Shear test 1-5 scaLe 5.0 1.0 1.3 3.3 LFC-FF showed no signs of shearing compared with the other materiaLs Freeze-thaw 1-5 scaLe 4.6 2.0 2.0 2.0 LFC-FF can test withstand Low temperatures without significant damage, in contrast with the other materiaLs

ThermaL SEE EXAMPLE

resistance test 16 _______ ________ ________ ________ _____________________ AppLication Minutes 5.2 10.4 10.0 6.7 LFC-FF can be time test appLied and finished in reduced time compared with the other materiaLs Water Litres 0.4 0.7 0.6 0.5 The other materiaLs consumption require more water to produce and controL compared _______________ _______________ ______ _______ _______ _______ with LFC-FF PermeabiLity Hours 98.3 96.0 100.7 96.0 No significant test 1 differences PermeabiLity Hours 23.0 24.3 24.0 24.3 No significant test 2 differences Reinforcement Years 100.0 1.2 1.2 100 PP fibres in externaL Life renders have an extended Life when compared to hair reinforcement Reinforcement Months 60.0 1.0 1.0 60.0 PP fibres have storage Life significantly increased storage Life in a wet aLkaLine environment.

Spray test 1-5 scaLe 4.0 1.0 1.0 4.0 PP fibres have enabLed reinforced _______________ _______________ ______ _______ _______ _______ Lime to be sprayed.

Reinforcement 15L bucket 0.0 1.4 4.0 0.0 CLump rate requiring clump rate discard was eLiminated in LFC-FF _______________ _______________ ______ _______ _______ _______ and LFC-CF.

ExampLe 3 -Adherence Tests 13 common construction substrates were tested (see next page) using the 5-point scaLe beLow: 1 = When dry, test pLaster can be Lifted off by hand 2 = When dry, test plaster can be torn off by hand 3 = When dry, test pLaster can be removed by tapping one-three times with a 75mm wide bolster 4 = When dry, test pLaster wilt not come off by tapping one -three times with a 75mm bolster but has cracked and shows some small signs of background separation S = When dry, plaster has full adherence, tested by trying to repeatedly chisel off with 75mm

bolster showing no sign of background separation

An average for each buiLding materiaL was caLculated; this series of tests was repeated twice over: Series Ambient Sampte size Average LFC-LCC-H LFC-H LFC-No Temp Sampte FF CF weight ÷1-2g 1 17°C 100 x 100 x 80g 4.1 2.3 2.5 2.8 _____ ______ 8mm ________ ____ ____ ____ ____ 2 17°C lOOxlOOx 80g 4 1.9 2A 3 _______ __________ 8mm ____________ _______ ______ ______ _______ 3 17°C 100 x 100 x 80g 4.1 1.8 2A 2.8 _____ ______ 8mm ________ ____ ____ ____ ____ Total 12.2 6.0 7.3 8.6 score Mean 4.1 2.0 2.4 2.9 score Series 1 data -Substrate LFC-FF LCC-H LFC-H LFC-CF Plasterboard 5 2 3 3 Fire board 5 3 3 3 Plyboard 5 1 1 1 Foil faced PIR insulation 3 1 1 1 Scratched glass 3 1 1 2 ALuminium 2 1 1 1 plastic 1 1 1 1 Drybrick 5 1 2 5 Dryblock 5 1 2 2 Reed 5 5 5 5 Metal Lath 5 5 5 5 Adobe 4 3 3 3 Heraklith board 5 5 5 5 Total score 53 30 33 37 Mean score 4.07692308 2.30769231 2.53846154 2.84615385

Conclusion -

LFC-FF has significantLy greater adherence compared with the other materials (generally), and shows a substantial and retiable adherence to a number of substrates that previously could not be effectiveLy plastered/rendered using a lime-based product, such as dry blocks and construction board.

ExampLe 4-Interface Crack Test PaneLs were made with 6 different substrates resuLting in 5 interfaces. The paneLs were pLastered over with 3-12mm of buiLding material and the interface cracking was measured.

ResuLts show Length of interface cracks (mm).

Test No Ambient Sample size LFC-FF LCC-H LFC-H LFC-CF Temp 1 17°C 700x250x3-l2mm 20 540 400 45 2 17°C 700x250x3-l2mm 0 630 245 70 3 17°C 700x250x3-l2mm 40 310 210 65 Total 60 1480 855.0 180.0 score _____________ ________________________ _________ _________ _________ _________ Mean 20 493 285.0 60.0 score LFC-FF shows significantLy Less interface cracking compared with the other materiaLs.

ExampLe S -Impact test A sphere of 60mm diameter weighing 300g was dropped on the sampLes from a height of 300mm; the number of times a sampLe withstood the impact before being compiomised was counted for each sampLe.

Test No Ambient SampLe size LFC-FF LCC-H LFC-H LFC-CF Temp 1 17°C 75mmx65mmx6mm 8 1 1 3 2 17°C 75mmx6smmx6mm 7 1 1 3 3 17°C 75mmx65mmx6mm 7 1 2 3 Total 22 3 4.0 9.0 score ____________ ______________________ __________ __________ __________ __________ Mean 7 1 1.3 3.0 score ____________ ______________________ __________ __________ __________ __________ LEC-FE can withstand a significantLy greater impact than the other materiaLs.

ExampLe 6 -Ike-form test Using a spring baLance (kiLo scaLe) the materiaL preforms were bridged between two points 450mm apart and puLLed at their centre. The action was recorded on video to estabLish the true faiLure point; measurements given in kg: Test No Ambient Sampte size LFC-FF LCC-H LFC-H LFC-CF Temp 1 17°C SOOxl5Oxl2mm 7.5 1 2 1 2 17°C SOOxlSOxl2mm 8 2.5 2 1.5 3 17°C SOOxlSOxlZmm 6.5 2 2.5 1.5 Total score 22 5.5 6.5 4.0 Mean score 7.3 1.83333 2.2 1.3 LFC-FF performs significantLy better than the other materiaLs in withstanding impact.

ExampLe 7 -Skim work Lightweight bLocks were turned on their sides to create a maximum background suction rate; these bLocks were skimmed with 2mm of pLaster. A 5-point scaLe was used to assess skimming: 1 = complete delamination of skim 2 = partiaL deLamination of skim 3 = adherence of skim but with defects 4 = good adherence with smaLL amount of defects = complete adherence with no defects Test No Ambient Sampte size LFC-FF LCC-H LFC-H LFC-CF Temp 1 19°C 75x440x2mm 4 1 1 2 2 19°C 75x440x2mm 4 1 1 2 3 19°C 75x440x2mm 4 1 1 3 Total score 12 3 3.0 7.0 Mean score 4 1 1.0 2.3 Skim work is not possibLe with any of the other materiaLs but has been enabLed by the deveLopment of LFC-FF.

ExampLe 8 -FLexibiLity Test Samples were sLowLy bent over graph paper untiL a significant crack appeared at which point the profiLe was pLotted on the graph. The crack point was aLso pLotted. One side was heLd at 900 to the graph and the point at which the crack appeared was measured against the verticaL pLane; resuLts given in angLe degrees.

Test No Ambient SampLe size LFC-FF LCC-H LFC-H LFC-CF Temp 1 19°C 180mm x 60mm x 4mm 18 69 70 37 2 19°C l8ommx6ommx4mm 19 61 72 45 3 19°C 180mm x 60mm x 4mm 17 78 71 52 Total 54 208 213.0 134.0 score ____________ _________________________ _________ __________ _________ _________ Mean 18 69 71.0 44.7 score ____________ _________________________ _________ __________ _________ _________ LFC-FF is significantLy more fLexible than the other materiaLs.

ExampLe 9 -TensiLe Strength Test The sampLes were cLamped between timber jaws at each end, and puLLed apart using a 25kg spring baLance untiL they fractured. A video was taken of the spring baLance scaLe to see cLearly what strain it reached before fracture; measurements given in kg: Test No Ambient Temp Sample size LFC-FF LCC-H LFC-H LFC-CF 1 17°C l3OXlOOXl2mm 19.5 2 2.5 6.5 2 17°C l3OXlOOXl2mm 22.5 2 3 4.5 3 17°°C l3OX100Xl2mm 25 1.5 2.5 5 Total score 67 5.5 8.0 16.0 Mean score 22 2 2.7 5.3 LEC-FE had a significantLy greater breaking strain compared with the other materiaLs.

ExampLe 10 -Fire Resistance Test Sampte sizes 80mm x 30mm x 3mm with an exposure area of 50mm x 30mm x 3mm had a 1995°C torch heEd at a 50mm distance and heated untiE they couLd no Longer support their weight and coLlapsed; this was timed and outcome provided beLow in minutes: Test No Ambient LFC-FF LCC-H LFC-H LFC-CF Temp 1 17°C 14.75 5.2 5.25 1.25 2 17°C 13.15 5.9 5.25 1.5 3 1TC 16.15 4.8 5 1 Total 44.05 15.9 15.5 3.8 score Mean 15 5.3 5.2 1.3 score LFC-FF is significantLy more resistant to a fLame than the other materiaLs, especiaLLy in comparison with LFC-CF.

ExampLe 11 -Finished Appearance Test A 5-point scaLe was used to score the LeveE of finish of each materiaL: 1 = Poor surface texture with high defect rate 2 = Poor surface texture with defects 3 = AcceptabLe surface texture with Low defect rate 4 = Good surface texture with no defects 5 = ExceLLent surface texture with no defects (where defects incLude cracks, unevenness and visibLe reinforcement showing through the materiaL surface).

Test No Ambient SampLe size LFC-FF LCC-H LFC-H LFC-CF Temp 1 19°C 390x680x20mm 4 2 3 1 2 19°C 390x680x20mm 5 2 2 1 3 19°C 390x680x20mm 5 3 3 1 Total score 14 7 8.0 3.0 Meanscore 5 3 2.7 1.0 The finished appearance of LFC-FF is significantLy better than the other materiaLs, especiaLLy in comparison with LFC-CF.

ExampLe 12 -Shrinkage Crack Test Wood Lath paneLs were constructed, divided into two, and then pLastered; the totaL sum of aLL visibLe cracks was then determined (mm): Test No Ambient Sample size LFC-FF LCC-H LFC-H LFC-CF Temp 1 19°C 39Ommx68Ommx2Omm 0 184 155 45 2 19°C 39Ommx 680mm x 20mm 0 210 145 60 3 19'C 39Ommx 680mm x 20mm 0 262 205 35 Total 0 656 505.0 140.0 score ___________ ___________________________ _________ _________ _________ _________ Mean 0 219 1683 46.7 score ___________ ___________________________ _________ _________ _________ _________ LFC-FF showed no signs of shrinkage, in contrast to the other materiaLs.

ExampLe 13 -Perimeter Test Wood Lath paneLs were constructed, divided into two, and then pLastered; the totaL sum of aLL individuaL perimeter cracks was then determined (mm): Test No Ambient Sample size LFC-LCC-LFC-H LFC-Temp FE H CF 1 19°C B9OmmxôSOmmx2Omm 520 1710 1550 1125 2 19°C B9Ommx 680mm x 20mm 620 1690 1500 1250 3 19°C 39Ommx68Ommx2Omm 400 1920 1625 1325 Totalscore 1540 5320 4675.0 3700.0 Meanscore 513 1773 1558.3 1233.3 There was significantLy Less perimeter shrinkage in LEC-EF when compared with the other materiaLs.

ExampLe 14 -Shear test A 5-point scaLe was used to score the LeveL of shear of each materiaL from 3.6N aerated bLocks (which were chosen as substrate because of their high background suction rate): 1 = significant shrinkage Leading to totaL deLamination 2 = shrinkage with partiaL deLamination 3 = shrinkage with deLamination by removing by hand 4 = a mix of deLamination and adherence with smaLL signs of shearing = no delamination or shear Test Ambient SampLe size aLL with 12mm LFC-FF LCC-H LFC-H LFC-CF No Temp of pLaster finish 1 19°C 440mm x 215mm x 75mm 5 1 1 3 2 19°C 440mm x 215mm x 75mm 5 1 1 3 3 19°C 44Ommx2lSmmx7Smm 5 1 2 4 Total 15 3 4.0 10.0 score _______________ ____________________________ ________ ________ ________ ________ Mean 5 1 1.3 3.3 score LFC-FF showed no signs of shearing compared with the other materiaLs.

ExampLe 15 -Freeze-thaw Test Samples were immersed in water for 10 minutes and pLaced in a freezer for 24 hours at -20°C. SampLes were aLLowed to defrost for 8 hours and the process repeated 4 times for each sampLe. A 5-point scaLe was used to score the LeveE of freeze-thaw resistance: 1 = sampLe has been compLetely compromised 2 = sampLe has been compromised but stiLE hoLds together 3 = sampLe has been affected requiring repair 4 = sampLe shows some signs of damage S = sampLe shows no signs of damage.

Test No Ambient Sample size Average LFC-FF LCC-H LFC-H LFC-Temp SampLe CF minus weight +1-2g 1 20°C 70x24x12mm 30g 5 2 2 2 2 20°C 70x24x12mm 30g 5 2 2 2 3 20°C 70x24x12mm 30g 4 2 2 2 Total score 14 6 6.0 6.0 Mean score 4.6 2.0 2.0 2.0 LFC-FF can withstand low temperatures without significant damage, in contrast with the other materiaLs ExampLe 16 -ThermaL Resistance Test Two boxes of PIR insuLation board were constructed with a partition space between the two; sampLes were seaLed in the partition space and the resistance of 40°C from the Lower box through the sampLe to the upper box (starting temperature 21°C) was measured at equiLibrium (3-4hr): Test Ambient Sample size LP-FF LFC-CF LFC-FF LFC-H PB PS LS-FF No Temp 1 21°C 240x140x12mm 26.4 28.7 27.5 28 28 25.5 28.8 2 21°C 240x140x12mm 26.4 28.6 27.5 28 28 25.5 28.7 3 21°C 240x140x12mm 26.4 28.7 27.4 28 28 25.5 28.7 Total 79.2 86 82.4 84.0 84.0 76.5 86.2 score __________ __________________ ______ _______ ______ ______ _______ _______ _______ Mean 26.4 28.7 27.5 28.0 28.0 25.5 28.7 score [P-FE: as per LFC-FE except pertite [P] was used instead of [C [S-FE: as per LS-FF except sand [5] was used instead of [C PB = pLasterboard PS = poLystyrene [C-FE performed better than, inter aLia, LFC-CF. The insuLation properties of [C-FE were further improved by using perLite instead of fine chaLk as the aggregate.

ExampLe 17 -AppLication Time Test Three wood Lath paneLs were constructed, each divided into two and then pLastered with a 20mm Layer of buiLding materiaL. Pre-and after-care was empLoyed when required. TotaL appLication time was recorded in minutes: Test No Ambient SampLe size LFC-FF LCC-H LFC-H LFC-CF Temp 1 17°C 390x680x20mm 5 12.5 10.5 7 2 17°C 390x680x20mm 5.25 8.5 11 7 3 17°C 390x680x20mm 5.25 10.25 8.5 6 Total score 15.5 31.25 30.0 20.0 Mean score 5 10 10.0 6.7 [C-FE can be appLied and finished in reduced time compared with the other materiaLs.

ExampLe 18 -Water Consumption Test [ightweight bLocks were pLastered with building materiaL and the water requirement was measured. [Pre-and post-damping down water was measured as weLl as product content.] Measurements given in L: Test No Ambient SampLe size LFC-FF LCC-H LFC-H LFC-CF Temp 1 17°C 440x215x12mm 0.375 0.7 0.6 0.475 2 17°C 440x215x12mm 0.375 0.7 0.6 0.475 3 17°C 440x215x12mm 0.375 0.7 0.6 0.475 Totalscore 1.125 2.1 1.8 1.4 Mean score 0.375 0.7 0.6 0.5 The other materiaLs require more water to produce and controL compared with LFC-FF.

ExampLe 19 -PermeabiLity test 1 Boxes of each buiLding materiat were made. Once dried to 11% wood moisture equivaLent (wme), SOOmL of water was spiayed inside through an entry hoLe. The hoLe was pLugged and wme readings were taken at timed intervaLs on aLL box sides to determine the rate of diffusivity (untiL the box returned to 11% wme). The same box was used to repeat the test.

Measurements given in wme/hr: Test Ambient Sample size Average LFC-FF LCC-LFC-H LFC-No Temp Sample H CF _______ __________ _____________________ weight _________ ______ _______ _______ 1 19°C 330x330x330x20 box 15.75kg 103 96 103 96 2 19°C 330x330x330x20 box 15.75kg 96 96 96 96 3 19°C 330x330x330x20 box 15.75kg 96 96 103 96 Total 295 288 302.0 288.0 score __________ _______________________ __________ _________ _______ ________ ________ Mean 98.3333 96 100.7 96.0 score There was no significant difference in permeability between LFC-FF and the othei materiaLs.

Example 20 -Permeability test 2 bog samples had 35g (3Sml) water added to them and placed in a room at 30°C. The time taken for the samples to return to a mass of bog was measured (hours): Test No Ambient Sample size Sample LFC-LCC-LFC-H LFC-Temp weight FF H CF 1 30°C 95x65x12 bOg 23 23 24 25 2 30°C 95x65x12 bOg 23 25 24 24 3 30°C 95x65x12 bOg 23 25 24 24 Total score 69 73 72.0 73.0 Mean 23 24.3 24.0 24.3 score There was no significant difference in permeability between LFC-FF and the other materials.

Example 21 -Reinforcement Life Accelerated degradation of PP fibres in a wet aLkaline environment was tested and shown to have a life expectancy of at [east 100 years. In contrast, three recently lime-pLastered properties (Dedham, Nedging and Weatheringsett, aLl in SuffoLk, UK) were checked for surviving hair content; as a result the expected lifespan of hair in these external renders was estimated to be 1.2 years. (Note that LFC-H is assumed to have the same degradation rate as LCC-H.) Thus PP fibres in external renders clearly have an extended Life when compared to hair reinforcement.

ExampLe 22 -Reinforcement Storage Life AcceLerated degradation of PP fibres in a wet aLkaLine environment was tested and shown to have a Life expectancy of at [east 100 years. It is thus expected that materiaLs comprising PP fibres as reinforcement can be stored for at Least 5 years (i.e. 60 months). In contrast, LCC-H and LFC-H dispLayed an average reinforcement degradation of 75% after onLy one month. Thus PP fibres cLearLy provide significantLy increased storage Life in a wet aLkaLine environment in comparison with hair reinforcement.

ExampLe 23 -Spray Test The buiLding materiaLs were put into a spray hopper to determine the abiLity to appLy the materiaLs via spraying both singLe and tripLe nozzLe spray heads were used. A 5-point scaLe was used to score the resuLts: 1 = the materiaL faiLed to spray 2 = the materiaL sprayed but not effectiveLy 3 = the materiaL sprayed but gave poor performance 4 = the materiaL sprayed effectiveLy enough to be productive = the product sprayed with fuLl efficiency Test No Ambient Approx. Sample LFC-FF LCC-H LFC-H LFC-CF Temp size 1 16°C 300mm diameter 4 1 1 4 2 16°C 300mm diameter 4 1 1 4 3 16°C 300mm diameter 4 1 1 4 Totalscore 12 3 3.0 12.0 Mean score 4 1 1.0 4.0 Pp fibres have enabLed reinforced Lime to be sprayed.

ExampLe 24 -Reinforcement Clump Rate Test 12 X 15L buckets of LFC-FF and of [FC-CF were made on the production site and no cLumps were found. In contrast, when 12 X 15L buckets of [CC-H and LFC-H were made, 17 and 12 cLumps (respectiveLy) were found which required discard. CLump rate requiring discard was therefore eLiminated in LEC-FE and LFC-CF.

Claims

CLaims 1. A pLiabLe materiaL for use in buiLding, said materiaL comprising: water, an aggregate of particle size Less than 5Op, a binding agent comprising at Least 70% caLcium hydroxide, and a pLuraLity of fibres.
2. A materiaL according to CLaim 1, wherein the aggregate is seLected from chaLk, marbLe, Limestone, caLcium siLicate or sand or mixture thereof.
3. A materiaL according to CLaim 1 or CLaim 2, wherein the aggregate is seLected from pumice, expanded cLay perLite or siLica gLass or a mixture thereof.
4. A materiaL according to any preceding cLaim wherein the binder incLudes a cLay, Linseed oil or casein.
5. A materiaL substantiaLly as herein described wherein the fibres are of non-biologicaL origin or coated with a materiaL of non-bioLogicaL origin.
6. A materiaL according to CLaim 5, wherein the fibres are seLected from poLypropyLene (PP), PMF, aLkaLine resistant gLass fibre, celLuLose or casein.
7. A materiaL according to any preceding cLaim, wherein the fibre Lengths are from 2 -mm in length.
8. A materiaL according to CLaim 7, wherein the fibre Length is from 2-40 mm.
9. A materiaL according to CLaim 8, wherein the fibre Length is from 2 -8 mm.
10. A materiaL according to any preceding cLaim, wherein the width of the fibres is from 2 -70p.
11. A material according to any preceding claim, wherein the fibre is present to an amount up to 20 kgm3
12. A material according to Claim 11 wherein the fibre is present in the materiaL in an amount of fro 2-4 kg per cubic metre.
13. A material according to Claim 12, wherein the materiaL is present in an amount of from 2.1 -4.0 kg per cubic metre.
14. A material according to Claim 13, wherein the material is present in an amount of from 3.0 -4.0 kgm3.
15. A pliabLe material substantiaLly as herein described.