Uk Building Regulations-A Must Know for All Devwlopers

8/20/2019 Uk Building Regulations-A Must Know for All Devwlopers

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Structure

The Building Regulations 2000

A A1 Loading A2 Ground movement

A3 Disproportionate collapse

APPROVED DOCUMENT


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Contents

PAGE

Use of guidance 3

Loading and Ground MovementThe Requirements A1/2 5

Guidance 6

Introduction 6

Section 1: Codes, standards and

references for all building types 7Introduction 7

References 7

Loading 7

Structural work of timber 7

Structural work of masonry 7

Structural work of reinforced,pre-stressed or plain concrete 7

Structural work of steel 7

Structural work of aluminium 7

Foundations 7

Ground movement (Requirement A2b) 8

Existing buildings 8

Section 2: Sizes of structural elementsfor certain residential buildings and othersmall buildings of traditional construction 9

General 9

Definitions 9

Section 2A: Basic requirements for stability 10

Section 2B: Sizes of certain timbermembers in floors and roofs for dwellings. Areas at risk from house longhorn beetle 11

Sizing of members 11

House longhorn beetle 11

S ti 2C Thi k f ll i t i

Construction ma

Loading on walls

End restraint

Openings, recess

Lateral support b

Interruption of lat

Small single-storeand annexes

Section 2D: Proportchimneys above the

Height to width r

Section 2E: Founda

Conditions relatin

Design provision

Minimum width o

Minimum depth o

Section 3: Wall clad

General

Technical approa

Loading

Fixings

Further guidance

Section 4: Roof cov

Materials

Re-covering of ro

Disproportionate CThe Requirement A

Guidance

Performance


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PAGE

DIAGRAMS

1. Size and proportion of residentialbuildings of not more than three storeys 13

2. Size and proportion of non-residentialbuildings and annexes 14

3. Determination of wall thickness 15

4. Parapet walls: height 16

5. Maximum floor area enclosed bystructural walls 17

6. Map showing wind speed in m/s formaximum height of buildings 18

7. Maximum height of buildings 19

8. Measuring storey and wall heights 20

9. Declared compressive strength of masonry units 22

10. Maximum span of floors 23

11. Differences in ground levels 24

12. Openings in a buttressing wall 25

13. Buttressing 26

14. Sizes of openings and recesses 27

15. Lateral support by floors 28

16. Lateral support at roof level 29

17. Size and location of openings 3018. Wall thickness 31

19. Lateral restraint at roof level 32

20. Proportions for masonry chimneys 33

21. Elevation of stepped foundation 34

22. Piers and chimneys 34

23. Foundation dimensions 34

24. Area at risk of collapse in the event of an accident 43

TABLES

1. Areas at risk from holonghorn beetle

2. Wall types considere

3. Minimum thickness oexternal walls, compaand separating walls

4. Imposed loads

5. Cavity wall ties

6. Declared compressivmasonry units complBS EN 771-1 to -5

7. Normalised compresmasonry units of claysilicate blocks complBS EN 771-1 and -2

8. Value of Factor ‘X’

9. Lateral support for w

10. Minimum width of str

11. Building classes

A CONTENTS


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THE APPROVED DOCUMENTS

This document is one of a series that has beenapproved by the First Secretary of State for thepurpose of providing practical guidance withrespect to the requirements of Schedule 1 to andRegulation 7 of the Building Regulations 2000 (SI2000/2531) for England and Wales. SI 2000/2531 has been amended by the Building (Amendment)Regulations 2001 (SI 2001/3335 ), by the Building(Amendment) Regulations 2002 (SI 2002/440), by

the Building (Amendment) (No. 2) Regulations2002 (SI 2001/2871), by the Building (Amendment) Regulations 2003 (SI 2003/2692) and by the Building (Amendment) Regulations 2004 (SI 2004/1465).

At the back of this document is a list of all thedocuments that have been approved and issuedby the Secretary of State for this purpose.

Approved Documents are intended to provideguidance for some of the more common

building situations. However, there may well bealternative ways of achieving compliance withthe requirements. Thus there is no obligation toadopt any particular solution contained in an Approved Document if you prefer to meet therelevant requirement in some other way.

Other requirements

The guidance contained in an Approved

Document relates only to the particularrequirements of the Regulations which thatdocument addresses. The building work willalso have to comply with the requirements ofany other relevant paragraphs in Schedule 1to the Regulations.

There are Approved Documents which giveguidance on each of the parts of Schedule 1and on Regulation 7.

LIMITATION ON REQUIREMENTS

In accordance with regulation 8, the requirementsin Parts A to K and N of Schedule 1 to theBuilding Regulations do not require anythingto be done except for the purpose of securing

product complying wspecification (as defia British Standard, otechnical specificatiocontracting party to which, in use, is equby a national or Euroa European Technicaand the conditions othe terms of the certguidance in the Appr

Regulation 7 on mat

Independent c

There are many UK pschemes. Such schewith the requirementwhich is appropriatematerial is to be usecertified may still con

Many certification boschemes are accred

Technical spec

Building Regulationspurposes: health andand the welfare and people. Standards arelevant guidance toto these consideratioaddress other aspecserviceability, or asprelate to health and sthe Regulations.

When an Approved Dto a named standardthe standard is the opublication. Howeverevised or updated bbody, the new versioof guidance providedrelevant requirement

The appropriate use with a European Tec

C

Use of guidance

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THE WORKPLACE (HEALTH,

SAFETY AND WELFARE)

REGULATIONS 1992

The Workplace (Health, Safety and Welfare)Regulations 1992 contain some requirementswhich affect building design. The mainrequirements are now covered by the BuildingRegulations, but for further information see:Workplace health, safety and welfare, TheWorkplace (Health, Safety and Welfare)Regulations 1992, Approved Code of Practice and Guidance; The Health and Safety

Commission, L24; Published by HMSO 1992;ISBN 0 11886 333 9.

The Workplace (Health, Safety and Welfare)Regulations 1992 apply to the common partsof flats and similar buildings if people such ascleaners and caretakers are employed to workin these common parts. Where the requirementsof the Building Regulations that are covered bythis Part do not apply to dwellings, the provisions

may still be required in the situations describedabove in order to satisfy the Workplace Regulations.

OTHER FORMS OF HOUSE

CONSTRUCTION

This Approved Document includes guidance onstructural elements of residential buildings oftraditional masonry construction. It is recognised,

however, that there are other suitable forms ofconstruction in use in the housing sector some ofwhich (e.g. timber framed) have been in commonuse for a number of years and have demonstratedan adequate performance in compliance with the A1 requirement. Such alternative forms includeprefabricated timber, light steel and precastconcrete framed construction.

A number of guidance documents relating to

these alternative forms are presently beingdeveloped by industry. The intention is toreference these in this Approved Documentas soon as they become available and areapproved by the Secretary of State.

EUROCODES

A USE OF GUIDANCE

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The Requirements

This Approved Document deals with the followingRequirements which are contained in the BuildingRegulations 2000 (as amended by SI 2001/3335,SI 2002/440, SI 2002/2871 and SI 2003/2692).

Requirement Limits on application

Loading

A1. (1) The building shall be constructed so that the combined dead,

imposed and wind loads are sustained and transmitted by it to the

ground:

(a) safely; and

(b) without causing such deflection or deformation of any

part of the building, or such movement of the ground, as will impair

the stability of any part of another building.

(2) In assessing whether a building complies with sub paragraph

(1) regard shall be had to the imposed and wind loads to which it islikely to be subjected in the ordinary course of its use for the purpose

for which it is intended.

Ground movement

A2. The building shall be constructed so that ground movement

caused by:

(a) swelling, shrinkage or freezing of the subsoil; or

(b) land-slip or subsidence (other than subsidence arising from

shrinkage, in so far as the risk can be reasonably foreseen), will notimpair the stability of any part of the building.

LOADING AND GROUND MOVEMENT

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Introduction

0.1 In the Secretary of State’s view therequirements of A1 and A2 will be met byfollowing the recommendations given in thedocuments listed in Section 1 or by adoptingthe guidance in Sections 2-4:

a. Section 1 is relevant to all building typesand lists Codes, Standards and otherreferences for structural design andconstruction but, where they do not give

precise guidance, consideration shouldbe given to paragraph 0.2.

b. Section 2 give sizes of structural elementsfor certain residential buildings and othersmall buildings of traditional construction.

c. Section 3 gives guidance on the supportand fixing of wall cladding.

d. Section 4 gives guidance where roofs are

to be re-covered as a material alteration asdefined in the Regulations.

0.2 The safety of a structure depends on thesuccessful combination of design and completedconstruction, particularly:

a. The design should be based on identificationof the hazards to which the structure is likelyto be subjected and assessment of the risks.

The selection of relevant critical situationsfor design should be made reflecting theconditions that can reasonably be foreseenduring future use.

b. Loading. Dead load, imposed load and windload should be in accordance with the currentCodes of Practice referred to in Section 1 ofthis document.

c. Properties of materials.

d. Detailed design and assembly ofthe structure.

e. Safety factors.

f. Workmanship.

The numeric values of safety factors, whether

Interim guidance on the des may be found in ‘Dynamic p requirements for permanentto crowd action, Interim Gui and design’ published by thStructural Engineers, Novem

Supplementary advice on thof grandstands and seating published in an Advisory Noof Structural Engineers, Jun

Guidance A1/2

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Introduction

1.1 This section is relevant to all building typesand lists codes, standards and other referencesfor structural design and construction.

References

1.2 Loading:

a. Dead and imposed loadsBS 6399-1:1996 Loading for buildings. Code ofpractice for dead and imposed loads.

b. Wind loads

BS 6399-2:1997 Loading for buildings. Codeof practice for wind loads

BRE digest 436 Parts 1, 2 and 3 (Brief guidance

for using BS 6399-2:1996).c. Imposed roof loads

BS 6399-3:1998 Loading for buildings. Code ofpractice for imposed roof loads.

1.3 Structural work of timber:

BS 5268-2:2002 Structural use of timber. Code ofpractice for permissible stress design, materialsand workmanship.

BS 5268-3:1998 Structural use of timber. Code ofpractice for trussed rafter roofs.

BS 8103-3:1996 Structural design of low-risebuildings. Code of practice for timber floors androofs for housing.

1.4 Structural work of masonry:

BS 5628-1:1992 Code of practice for use of

masonry. Structural use of unreinforced masonry.

BS 5628-2:2000 Code of practice for use ofmasonry. Structural use of reinforced andpre-stressed masonry.

BS 5628-3:2001 Code of practice for use ofmasonry. Materials and components, design

BS 8110-3:1985 StruDesign charts for sinreinforced beams an

BS 8103-4:1995 Strubuildings. Code of pconcrete floors for ho

1.6 Structural wo

BS 5950-1:2000 Strubuilding. Code of praand continuous conswelded sections.

BS 5950-2:2001 Strubuilding. Specificatioand erection, hot roll

BS 5950-3-1:1990 Sbuilding. Design in c

of practice for desigcomposite beams.

BS 5950-4:1994 Struin building. Code of composite slabs with

BS 5950-5:1998 Codof cold formed thin g

BRE Digest 437 Indu

mezzanine and raise

1.7 Structural wo

BS 8118-1:1991 StruCode of practice for

BS 8118-2:1991 StruSpecification for matand protection.

1.8 Foundations:

BS 8002:1994 Coderetaining structures.

BS 8004:1986 Code

Section 1: Codes, standards andfor all building types


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Ground movement

(Requirement A2b)

1.9 There may be known or recorded

conditions of ground instability, such as thatarising from landslides, disused mines orunstable strata which, if ignored, can have adevastating effect on the safety of a buildingand its environs. Such conditions should betaken into account in the design of the buildingand its foundations. Attention is drawn to DOEPlanning Policy Guidance Note 14 Developmenton unstable land (obtainable from The StationeryOffice), which sets out the broad planning andtechnical issues relating to development onunstable land.

The Department has also sponsored a seriesof reviews aimed at determining the scale andnature of problems arising from mining instability,natural underground cavities and adversefoundation conditions. Databases of bothsubsidence incidents and subsidence potentialproduced from these reviews are available fromthe following licence holders:

British Geological Survey, Sir Kingsley DunhamCentre, Keyworth, Nottingham NG12 5GG.

Landmark, 7 Abbey Court, Eagle Way, Exeter,Devon EX2 7HY.

Peter Brett Associates, 16 Westcote Road,Reading, Berkshire RG20 2DE.

Catalytic Data Ltd, The Spinney, 19 WoodlandsRoad, Bickley, Kent BRI 2AD.

The reports from these reviews, which include1:250,000 scale maps showing the distributionof the physical constraints, are available from thefollowing organisations:

Arup Geotechnics, 1991. Review of mininginstability in Great Britain.

Obtainable from Arup Geotechnics, Bede House, All Saints, Newcastle-upon-Tyne NE1 2EB.

Applied Geology Ltd, 1994. Review of instabilitydue to natural underground cavities in GreatBritain.

Obtainable from Kennedy & Donkin Ltd,

Existing buildings

1.10 Compliance with Parrequired in certain classes obuilding, subject to the contand 6. Guidance relevant torelated to ‘change of use’ isdocuments:

a. BRE Digest 366: StructuExisting Buildings for Ch

b. The Institution of Structu Appraisal of Existing Str

Note: With reference to the in the above mentioned InstEngineers report the choicefactors should be made to scircumstances of each case

A1/2 CODES, STANDARDS AND REFERENCES FOR ALL B



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Section 2: Sizes of structural elecertain residential buildings and

buildings of traditional constructGeneral

2.1 This section is presented as follows:

Section 2A

Basic requirements for stability.

Section 2BSizes of certain timber members in floors androofs for dwellings.

Areas at risk from house longhorn beetle.

Section 2C

Thickness of masonry walls in certain residentialbuildings of not more than three storeys, small

single-storey non-residential buildings and annexes.Section 2D

Proportions for masonry chimneys.

Section 2E

Foundations of plain concrete.

2.2 Section 2A gives general rules which mustbe observed in following Sections 2B and 2C.

Sections 2B to 2E may be used independentlyof each other.

Throughout this section the diagrams are onlyillustrative and do not show all the details ofconstruction.

Definitions

2.3 The following meanings apply to terms

throughout this section:Buttressing wall A wall designed andconstructed to afford lateral support to anotherwall perpendicular to it, support being providedfrom the base to the top of the wall.

Cavity width The horizontal distance betweenth t l f it ll

Pier A member whicof a wall, in the formintervals along the wsupport to the wall tosecurely tied.

Separating wall A w

common to adjoiningto meet the requirem

Spacing The distanccentres of any two athe same type, measceiling or roof structu

Span The distance mline of a member betadjacent bearings or

Supported wall A wafforded by a combipiers or chimneys acfloor(s) or roof.

Wind load The load pressure or suction.


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Section 2A: Basic requirements for

2A1 This section must be used in conjunctionwith sections 2B and 2C and its principles relate

to all forms of low-rise residential buildings.

2A2 Adequate provision shall be made toensure that the building is stable under the likelyimposed and wind loading conditions. This willcommonly necessitate meeting the followingrequirements:

a. That the overall size and proportioningof the building are limited in accordance

with the specific guidance for each form ofconstruction.

b. That a suitable layout of walls (both internaland external) forming a robust 3 dimensionalbox structure in plan is constructed withrestriction on the maximum size of cellsmeasured in accordance with the specificguidance for each form of construction.

c. That the internal and external walls are

adequately connected either by masonrybonding or by using mechanical connections.

d. That the intermediate floors and roof are ofsuch construction and interconnection withthe walls that they provide local supportto the walls and also act as horizontaldiaphragms capable of transferring the windforces to buttressing elements of the building.

Note: A traditional cut timber roof (i.e. usingrafters, purlins and ceiling joists) generally hassufficient built in resistance to instability andwind forces (e.g. from hipped ends, tiling battens,rigid sarking or the like). However, the needfor diagonal rafter bracing equivalent to thatrecommended in BS 5268-3:1998 or Annex H ofBS 8103-3:1996 for trussed rafter roofs shouldbe considered especially for single-hipped andnon-hipped roofs of greater than 40° pitch to

detached houses.

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Sizing of members

2B1 Guidance on the sizing of certain membersin floors and roofs is given in ‘Span tables forsolid timber members in floors, ceilings and roofs(excluding trussed rafter roofs) for dwellings’,published by TRADA, available from Chiltern

House, Stocking Lane, Hughenden Valley, HighWycombe, Bucks HP14 4ND.

Alternative guidance is available in BS 5268-2:2002 Code of practice for permissible stress design,materials and workmanship, BS 5268-3:1998,Code of practice for trussed rafter roofs andBS 8103-3:1996 Structural design of low-risebuildings, Code of Practice for timber floors androofs for dwellings.

Table 1 Areas at risk from house longhorn beetle

Geographical area

In the Borough of Bracknell Forest the parishes of Sandhurst and Crowthorne.

The Borough of Elmbridge

In the District of Hart, the parishes of Hawley and Yateley

The District of Runnymede

The Borough of Spelthorne

The Borough of Surrey Heath

In the Borough of Rushmoor, the area of the former district of Farnborough

The Borough of Woking

House longhor

2B2 In the geograpTable 1, softwood timor fixed in the roof spwithin the void spaceadequately treated to

house longhorn beetGuidance on suitableis given within the BrDamp-Proofing Assorevision), available fr Vernongate, South S

Section 2B: Sizes of certain timbin floors and roofs for dwellings.

risk from house longhorn beetle

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Section 2C: Thickness of walls in cesmall buildings

Application2C1 This section applies to the followingbuilding types:

a. residential buildings of not more thanthree storeys;

b. small single-storey non-residentialbuildings;

c. small buildings forming annexes toresidential buildings (including garagesand outbuildings).

Wall types

2C2 Only the types of wall given in Table 2,which must extend to the full storey height, andparapet walls are considered in this section.

The use of this section2C3 When using this section it should benoted that:

a. this section must be used in conjunctionwith Section 2A;

b. if wall thickness is to be determinedaccording to paragraphs 2C5 to 2C13, allappropriate design conditions given in this

section must be satisfied;

c. walls should comply with the relevantrequirements of BS 5628: Part 3: 2001, exceptas regards the conditions given in paragraphs2C4 and 2C14 to 2C38;

d. in formulating the guidance of this section theworst combination of circumstances likely toarise was taken into account. If a requirement

of this part is considered too onerous in aparticular case it may be appropriate toconsider a minor departure on the basisof judgement and experience, or to showadequacy by calculation in respect of theaspect of the wall which is subject to thedeparture rather than for the entire wall;

e. the guidance given is bacompressive strengths obeing not less than indica

BS 5628-1:1992 gives desigwhere the suitability for use other compressive strength

Conditions relating

of which the wall fo2C4 This Section applies having proportions within thparameters (see Diagrams 1

a. residential buildings ofthree storeys:

i. the maximum heightmeasured from the lo

level adjoining the bupoint of any wall or rgreater than 15m, suof paragraph 2C16;

ii. the height of the builexceed twice the leabuilding W1;

iii. the height of the winexceed twice the leaW2 where the projecthe width W2;

b. small single-storey nonheight H should not excthe greatest length or wshould not exceed 9m (ssubject to the limits of p

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c. annexes: height H as variously indicated inDiagram 2 should not exceed 3m, subject tothe limits of paragraph 2C16.

Thickness of walls

2C5 General wall thickness may be determinedaccording to this section provided:

a. conditions relating to the building of whichthe wall forms part (see paragraphs 2C4,2C14 to 2C16, 2C38 ); and

b. conditions relating to the wall (see paragraphs2C17 to 2C37 ) are met. (See Diagram 3.)

wide. The wall ties sspacing of 900mm a450mm, which is equmetre. Wall ties shounot more than 300mdistance of 225mm fopenings, movemen

selection of wall tieswidths refer to Tablewall ties refer to para

For external walls, coseparating walls in ccombined thickness should not be less th

THICKNESS OF WALLS IN CERTAIN SMALL BUILDING

Diagram 1 Size and proportion of residential buildings of not m

See para 2C4


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A1/2 THICKNESS OF WALLS IN CERTAIN SMALL BUILDI

Diagram 2 Size and proportion of non-residential buildings and ann

See paras 2C4b and 2C4c


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Table 3 Minimum thickness of certain external walls, comparseparating walls

Height of wall Length of wall

Not exceeding 3 5m Not exceeding 12m


Diagram 3 Determination of wall thickness

See para 2C5


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except for a wall in the lowest storey of a threestorey building, carrying load from both upper

storeys, which should have a thickness asdetermined by the equation or 140mm whicheveris the greatest.

2C11 Parapet walls: The minimum thicknessand maximum height of parapet walls should beas given in Diagram 4.

2C14 Maximum floor areathis section assumes that no

structural walls on all sides that no floor without a strucexceeds 36m2. (See Diagram

2C15 Imposed loads on roceilings: The design considthis section are intended to imposed loads given in Tabl


Diagram 4 Parapet walls: height

See para 2C11


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Table 4 Imposed loads

Element Loading

Distributed loadsRoof 1.00kN/m² for spans not exceeding 12m 1.5kN/m² for spans not exceeding 6m Floors Distributed load: 2.00kN/m² Ceilings Distributed load: 0.25kN/m² together with concentrated load: 0.9kN

2C18 Rules of measurement for heights ofwalls and storeys: The height of a wall or astorey should be measured in accordance with

2C20 Masonry unitbonded and solidly pconstructed of maso

a. clay bricks or bloBS 6649:1985 or

b. calcium silicate bBS 6649:1985 or

c. concrete bricks oor BS EN 771-3 o

d. square dressed nrequirements desBS 5628-3:2001;

e. manufactured stoBS EN 771 5


Diagram 5 Maximum floor area enclosed by structural walls

See para 2C14

A1/2



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Diagram 6 Map showing wind speeds in m/s for maximum height o

See para 2C16


20/47


Diagram 7 Maximum height of buildings

See para 2C16



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Diagram 8 Measuring storey and wall heights

See para 2C18



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Table 5 Cavity wall ties

Nominal cavity width mm

(Note 1)

50 to 75

76 to 90

91 to 100

101 to 125

126 to 150

151 to 175

176 to 300

Tie length mm

(Note 2)

200

225

225

250

275

300

(See Note 2)

Permissible type of tie

Tie shape in accordance

with BS 1243*

Butterfly, double triangle or vertical twist

Double triangle or vertical twist

Double triangle (Note 3) or vertical twist

Vertical twist

Vertical twist

Vertical twist

Vertical twist style

Typeselec

load

*Although BSwithdrawn on(types) given

document ca

Notes:

1. Where face insulated blocks are used the cavity width should be measured from the face of the masonry u

2. The embedment depth of the tie should not be less than 50mm in both leaves. For cavities wider than 180cavity width plus 125mm and select the nearest stock length.

3. Double triangle ties of this shape having a strength to satisfy Type 2 of DD 140-2* are manufactured. Specconsulted if 225mm long double triangle format ties are needed for 91 to 100mm cavities.

4. Where BS EN 845-1 ties are used reference needs to be made additionally to DD 140-2* for the selection to the performance levels given in DD 140-2.

Table 6 Declared compressive strength of masonry units comBS EN 771-1 to -5 (N/mm2 )

Masonry unit Clay masonry units to Calcium silicate masonry Aggrega BS EN 771-1 units to BS EN 771-2 concre mason units t BS EN 77

Condition A (See Diagram 9)

Brick Group 1 Group 2 Group 1 Group 2 6.0 6.0 9.0 6.0 9.0

Block See Table 7 See Table 7 See Table 7 See Table 7 2.9*

Condition B (See Diagram 9)


Block See Table 7 See Table 7 See Table 7 See Table 7 7.3* Condition C (See Diagram 9)


Block See Table 7 See Table 7 See Table 7 See Table 7 7.3*



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Diagram 9 Declared compressive strength of masonry units

See para 2C21



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Table 7 Normalised compressive strength of masonry units osilicate blocks complying with BS EN 771-1 and 2 (N/

Standard

Clay masonry units to BS EN 771-1Calcium silicate masonry units toBS EN 771-2

Condition (See Diagram 9)

A

B

C

Group 1 masonry unit

5.0

7.5

15.0

Notes:

1. Values in this table are normalised compressive strengths (N/mm²). Compressive strengths of masonry units

2. The table applies to clay and calcium silicate block masonry units where the work size exceeds 337.5mm

3. Group 1 masonry units have not more than 25% formed voids (20% for frogged bricks). Group 2 masonry

25%, but not more than 55%.

2C22 Mortar: Mortar should be:

a.

i. Mortar designation (iii) according toBS BS 5628-3:2001.

ii. Strength class M4 according to

BS EN 998-2.

iii. 1:1:5 or 6 CEM 1, lime and fine aggregatemeasured by volume of dry materials, or

b. of equivalent or greater strength anddurability to the specification in a. above.

Loading on walls

2C23 Maximum span of floors: The maximum

span for any floor supported by a wall is 6mwhere the span is measured centre to centre ofbearing (see Diagram 10).

2C24 Other loading conditions:

a. Vertical loading on walls should be distributed.This may be assumed for concrete floorslabs, precast concrete floors, and timberfloors designed in accordance with section

2B, and where the bearing length for lintels is150mm or greater. Where a lintel has a clearspan of 1200mm or less the bearing lengthmay be reduced to 100mm.

b. Differences in level of ground or other solidconstruction between one side of the walland the other should be less than 4 times the

End restraint

2C25 Vertical Later

The ends of every wotherwise securely ti

Diagram 10 Max

See para 2C23


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Diagram 11 Differences in ground levels

See para 2C24b



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a. half the thickness required by this section foran external or separating wall of similar heightand length less 5mm; or

b. 75mm if the wall forms part of a dwellinghouse and does not exceed 6m in total heightand 10m in length; and

to the wall. Piers width of 190mm

b. the sectional are(excluding openishould be not lesfor a pier in the s

Diagram 12 Openings in a buttressing wall

See para 2C26



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2C29 Dimensional criteria for openings andrecesses:

The dimensional criteria are given in Diagram 14and Table 8.

No openings should be provided in walls belowground floor except for small holes for servicesand ventilation, etc. which should be limitedto a maximum area of 0.1m² at not less than2m centres.

2C30 Chases:

Lateral support by r

2C32 A wall in each storey extend to the full height of thorizontal lateral supports to

of the wall at right angles to2C33 Floors and roofs sh

a. act to transfer lateral forbuttressing walls, piers o

b. be secured to the suppo


Diagram 13 Buttressing

See para 2C27



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Diagram 14 Sizes of openings and recesses

See para 2C29

Table 8 Value of Factor ‘X’ (see Diagram 14)

Span of timber floor into wall Span of floor Minimum is parallel max maNature of Maximum thickness of to wall 4.5m 6.0roof span roof span (m) wall inner (mm)

Value of f Roof spans Not 100 6 6 6parallel to wall applicable 90 6 6 6

Timber roof 9 100 6 6 5



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specifications including material references 1 or3 (austenitic stainless steel). The declared tensilestrength of tension straps should not be less

than 8kN.

Tension straps need not be provided:

a. in the longitudinal direction of joists in housesof not more than 2 storeys, if the joists areat not more than 1.2m centres and have atl t 90 b i th t d ll

d. where floors are at or abon each side of a suppocontact between the floo

continuous or at intervalWhere contact is intermcontact should be in lineplan (see Diagram 15(e))

2C36 Gable walls should bshown in Diagram 16(a) and

Diagram 15 Lateral support by floors

See para 2C35



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Interruption of lateral support

2C37 Where an opening in a floor or roof for a

stairway or the like adjoins a supported wall andinterrupts the continuity of lateral support, thefollowing conditions should be satisfied for thepurposes of Section 2C:

a. the maximum permitted length of the openingis to be 3m, measured parallel to the supported

Small single-st

buildings and a

2C38 Size and prop

i. General

The guidance given circumstances:

Diagram 16 Lateral support at roof level

See para 2C36



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Diagram 17 Size and location of openings

See para 2C38



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Diagram 18 Wall thickness

See para 2C38



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Walls which do not contain a major openingbut exceed 2.5m in length or height should bebonded or tied to piers for their full height at notmore than 3m centres as shown in Diagram 18a.Walls which contain one or two major openings

(iv) Horizontal lateral re

Walls should be tied horizon2m centres to the roof strucbase of gables and along roin Diagram 19 with straps fix

Diagram 19 Lateral restraint at roof level

See para 2C38

A1/2

S ti 2D P ti f


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Section 2D: Proportions for maschimneys above the roof surface

Height to width relationship2D1 Where a chimney is not adequatelysupported by ties or securely restrained in anyway, its height if measured from the highest pointof intersection with the roof surface, gutter, etc.should not exceed 4.5W, provided the density ofthe masonry is greater than 1500kg/m3, where:

W is the least horizontal dimension of the

chimney measured at the same point ofintersection, and

H is measured to the top of any chimney pot orother flue terminal (see Diagram 20).

Diagram 20 Proportions for masonrychimneys

See para 2D1

S ti 2E F d ti f l i A1/2


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Conditions relating to the ground

2E1 There should not be:

a. non-engineered fill (as described in BREDigest 427 ) or wide variation in groundconditions within the loaded area; nor

b. weaker or more compressible ground atsuch a depth below the foundation as couldimpair the stability of the structure.

Design provisions

2E2 The following design provisions relate tofoundations:

a. the foundations should be situated centrallyunder the wall;

b. for foundations in chemically aggressivesoil conditions guidance in BS 8500-1 andBRE Special Digest 1 should be followed.In non-aggressive soils, concrete should

be composed of Portland cement to BS EN197-1 and -2 and fine and coarse aggregateconforming to BS EN 12620 and the mixshould comply with one of the followingrecommendations:

i. in proportion of 50kg of Portland cementto not more than 200kg (0.1m3 ) of fineaggregate and 400kg (0.2m3 ) of coarseaggregate; or

ii. grade ST2 or grade GEN I concrete toBS 8500-2;

c. minimum thickness T of concrete foundationshould be 150mm or P, whichever is thegreater where P is derived using Table 10and Diagram 23. Trench fill foundations maybe used as an acceptable alternative to stripfoundations;

d. foundations stepped on elevation shouldoverlap by twice the height of the step, bythe thickness of the foundation, or 300mm,whichever is greater (see Diagram 21).

For trench fill foundations the overlap shouldbe twice the height of the step or 1m,

Section 2E: Foundations of plain co

Diagram 21 Elevation

foundationSee paras 2E2d and e

Diagram 22 Piers and

See para 2E2f

Diagram 23 Foundatio

See para 2E2c

FOUNDATIONS OF PLAIN CONCRETE

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Table 10 Minimum width of strip footings

Total load of loa(

Type of ground 20 30 (including Condition Field testengineered fill) of ground applicable Minimum wid

I Not inferior to Requires at least a pneumatic In each casRock sandstone, limestone or other mechanically operated or firm chalk pick for excavation

II Requires pick for excavation. 250 300 Gravel or sand Medium dense Wooden peg 50mm square in cross section hard to drive beyond 150mm

III Can be indented slightly by thumb 250 300 Clay StiffSandy clay Stiff

IV Thumb makes impression easily 300 350 Clay FirmSandy clay Firm V Can be excavated with a spade. 400 600Sand Loose Wooden peg 50mm square inSilty sand Loose cross section can be easily driven

Clayey sand Loose VI Finger pushed in up to 10mm 450 650 Silt Soft Clay SoftSandy clay SoftClay or silt Soft

VII Finger easily pushed in up to 25mm RefeSilt Very softClay Very softSandy clay Very softClay or silt Very soft

The table is applicable only within the strict termsof the criteria described within it.

Minimum depth of strip

foundations

2E4 Except where strip foundations arefounded on rock, the strip foundations shouldhave a minimum depth of 0.45m to theirunderside to avoid the action of frost. This depth,however, will commonly need to be increased inareas subject to long periods of frost or in order

f h l di i f d

Section 3: Wall cladding A1/2


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General

3.1 Wall cladding presents a hazard if itbecomes detached from the building. Thissection provides guidance on the supportand fixing of wall cladding. An acceptablelevel of safety can be achieved by differentmeans depending on the type and location ofthe cladding. The guidance given relates toall forms of cladding, including curtain wallingand glass facades. It is not intended to provideguidance concerning the weather resistance

of wall cladding which is included in ApprovedDocument C, Site preparation and resistance tomoisture, or guidance on resistance to spread offire which is included in Approved Document B,Fire safety, or guidance in relation to soundinsulation, which is included in ApprovedDocument E, Resistance to the passageof sound.

Technical approach

3.2 The cladding will meet the safetyrequirement if:

a. the cladding is capable of safely sustainingand transmitting to the supporting structureof the building all dead, imposed and windloads, and

b. the cladding is securely fixed to andsupported by the structure of the building.This shall comprise both vertical supportand horizontal restraint, and

c. provision is made, where necessary, toaccommodate differential movement of thecladding and the supporting structure of thebuilding, and

d. the cladding and its fixings (includingany support components) are of durable

materials; the design life of the fixings beingnot less than that of the cladding. Fixingsshall be corrosion resistant and of a materialtype appropriate for the local environment.

Loading

3.5 Where the wall claddfunction as pedestrian guard

vertical drops of 600mm or vehicle barrier, then accounthe additional imposed load Approved Document K, Procollision and impact.

3.6 Where the wall claddsafely withstand lateral presan appropriate design loadi6399 Part 1 and the Guide t

Grounds (4th Edition, 1997)

Fixings

3.7 The selection of fixingcladding should be determinconsideration of the proven fixing and the risks associatapplication. In this regard apdesignated as being either n

the failure of a single fixing cdetachment of the cladding)failure or excessive movemeresults in load sharing by adthe required reliability of theaccordingly.

Note: Attention is drawn to tof anchors with an ETA (Eur Approval) gained in accorda

requirements of ETAG 001 GEuropean Technical Approvfor use in Concrete Parts 1-redundant and non-redundaPart 6 which covers ‘Anchoin non-structural applicationeffectively be regarded as cuse. The UK definition of ‘mcontained in an annexe to this framed in such a way that

be validated as to whether othis category without calculmay be downloaded in Engli

3.8 The strength of fixingfrom tests using materials rematerial into which the fixing

Section 3: Wall cladding

WALL CLADDING

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in ‘Use of anchors with European Technical Approvals. UK Guidance – Distinctionbetween cracked and non-cracked concrete’.This is available on the BBA websitewww.bbacerts.co.uk click tab ‘ETA’.

Further guidance

3.9 The use of large panels of glass incladding of walls and roofs where the claddingis not divided into small areas by load-bearingframing requires special consideration. Guidanceis given in the following documents:

The Institution of Structural Engineers’ Report on

‘Structural use of glass in buildings’ dated 1999,available from 11 Upper Belgrave Street, LondonSW1X 8BH.

‘Nickel sulfide in toughened glass’ published bythe Centre for Window Cladding and Technologydated 2000.

3.10 Further guidance on cladding is given inthe following documents:

The Institution of Structural Engineers’ Report on‘ Aspects of Cladding’ dated 1995.

The Institution of Structural Engineers’ Reporton ‘Guide to the structural use of adhesives’dated 1999.

BS 8297:2000 Code of practice for the designand installation of non-load-bearing pre-castconcrete cladding.

BS 8298:1994 Code of practice for the design andinstallation of natural stone cladding and lining.

3.11 Additional guidance on fixings is given inthe following documents:

ETAG No. 001 1997 Guideline for EuropeanTechnical Approvals of Metal Anchors for use inConcrete, European Organisation for Technical Approvals (EOTA), Brussels. All EOTA parts maybe downloaded in English from www.eota.be.

English version published by the British Boardof Agreement, PO Box 195, Bucknalls Lane,Garston, Watford, Hertfordshire WD25 9BA.

Part 1 Anchors in general.

Part 2 Torque controlled anchors.

Guidance notes pubFixings Association, Technology, Henry SSouth Yorks S3 7EQ

Guidance Note: ProcConstruction Fixings

Guidance Note: Eurofor Construction Fixi

Guidance Note: Anc

Guidance Note: Fixin

Guidance Note: Anc

Guidance Note: Bon

Guidance Note: Hea Anchors (1997).

Guidance Note: FixinBlockwork (1997).

Guidance Note: Und

Guidance Note: Fixin

Section 4: Roof covering A1/2

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Materials

4.1 All materials used to cover roofs,

including transparent or translucent materials,but excluding windows of glass in residentialbuildings with roof pitches of not less than15°, shall be capable of safely withstandingthe concentrated imposed loads upon roofsspecified in BS 6399: Part 3.

Re-covering of roofs

4.2 The re-covering of roofs is commonlyundertaken to extend the useful life of buildings.Roof structures may be required to carryunderdrawing or insulation provided at a timelater than their initial construction. This sectionprovides guidance on determining whether suchwork to a roof constitutes a material alterationunder the Building Regulations.

4.3 Where the work involves a significantchange in the applied loading the structuralintegrity of the roof structure and the supportingstructure should be checked to ensure thatupon completion of the work the building is notless compliant with Requirement A1 than theoriginal building.

4.4 A significant change in roof loading iswhen the loading upon the roof is increased bymore than 15%.

4.5 Where such checking of the existing roofstructure indicates that the construction is unableto sustain any proposed increase in loading (e.g.due to overstressed members or unacceptabledeflection leading to ponding), appropriatestrengthening work or replacement of roofingmembers should be undertaken. This is classifiedas a material alteration.

4.6 In carrying out the checks mentioned in

paragraph 4.3 an increase of stress in a structuralmember arising from increased loading doesnot necessarily indicate that the roof structure isless compliant than the original roof provided anadequate factor of safety is maintained.

4.7 Where work will significantly decrease

Section 4: Roof covering

DISPROPORTIONATE COLLAPSE

The Requirement

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This Approved Document deals with the followingRequirements which are contained in the Building

Regulations 2000 (as amended by SI 2001/3335,SI 2002/440, SI 2002/2871 and SI 2003/2692 ).

Requirement Limits on application

Disproportionate collapse

A3. The building shall be constructed so that in the event of an accidentthe building will not suffer collapse to an extent disproportionate to

the cause.

The Requirement

Guidance A3

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Performance

In the Secretary of State’s view the Requirement

of A3 will be met by an appropriate choiceof measures to reduce the sensitivity of abuilding to disproportionate collapse shouldan accident occur.

Introduction

0.1 The guidance in Section 5 deals with themeans of meeting this performance criterion.

Guidance

Section 5: Reducing the sensitiv


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Section 5: Reducing the sensitivbuilding to disproportionate coll

event of an accident5.1 The requirement will be met byadopting the following approach for ensuringthat the building is sufficiently robust tosustain a limited extent of damage or failure,depending on the class of the building,without collapse.

a. Determine the building class from Table 11.

b. For Class 1 buildings – Provided thebuilding has been designed and constructedin accordance with the rules given in this Approved Document, or other guidancereferenced under Section 1, for meetingcompliance with requirement A1 and A2 innormal use, no additional measures are likelyto be necessary.

Table 11 Building classes

Classes Building type and occupancy 1 Houses not exceeding 4 storeys

Agricultural buildings

Buildings into which people rarely go, provided no part of the building is closer to anodo go, than a distance of 1.5 times the building height

2A 5 storey single occupancy houses

Hotels not exceeding 4 storeys

Flats, apartments and other residential buildings not exceeding 4 storeys

Offices not exceeding 4 storeys

Industrial buildings not exceeding 3 storeys

Retailing premises not exceeding 3 storeys of less than 2000m² floor area in each sto

Single-storey educational buildings

All buildings not exceeding 2 storeys to which members of the public are admitted anexceeding 2000m² at each storey

2B Hotels, flats, apartments and other residential buildings greater than 4 storeys but no

Educational buildings greater than 1 storey but not exceeding 15 storeys

Retailing premises greater than 3 storeys but not exceeding 15 storeys

Hospitals not exceeding 3 storeys

c. For Class 2A buhorizontal ties, osuspended floorsin the Codes andparagraph 5.2 fowall constructionparagraph 5.3 be

d. For Class 2B buhorizontal ties, asStandards listed uand load-bearingbeing defined in pwith effective verCodes and Stand5.2, in all suppor

Alternatively, check that upon the notional Key elements

REDUCING THE SENSITIVITY OF THE BUILDING TO A3 DISPROPORTIONATE COLLAPSE IN THE EVENT OF


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Alternatively, check that upon the notionalremoval of each supporting column and eachbeam supporting one or more columns, or anynominal length of load-bearing wall (one at atime in each storey of the building), the building

remains stable and that the area of floor at anystorey at risk of collapse does not exceed 15%of the floor area of that storey or 70m2, whicheveris smaller, and does not extend further than theimmediate adjacent storeys (see Diagram 24).

Where the notional removal of such columnsand lengths of walls would result in an extent ofdamage in excess of the above limit, then suchelements should be designed as a ‘key element’

as defined in paragraph 5.3 below.e. For Class 3 buildings – A systematic

risk assessment of the building should beundertaken taking into account all the normalhazards that may reasonably be foreseen,together with any abnormal hazards.

Critical situations for design should be selectedthat reflect the conditions that can reasonablybe foreseen as possible during the life of thebuilding. The structural form and concept andany protective measures should then be chosenand the detailed design of the structure andits elements undertaken in accordance withthe recommendations given in the Codes andStandards given in paragraph 5.2.

5.2 Details of the effective horizontal andvertical ties, together with the design approachesfor checking the integrity of the building followingthe notional removal of vertical members andthe design of key elements, are available in thefollowing Codes and Standards:

BS 5628-1:1992 Structural use of unreinforcedmasonry. Code of practice for use of masonry.

BS 5950-1:2000 Structural use of steelworkin building. Code of practice for design. Rolledand welded sections.

BS 8110-1:1997 Structural use of concrete. Code of practice for design and construction.

BS 8110-2:1985 Structural use of concrete. Codeof practice for special circumstances.

5 3 Definitions

Key elements

A ‘key element’, as referred should be capable of sustaidesign loading of 34kN/m2 ahorizontal and vertical direcat a time) to the member ancomponents (e.g. cladding eto the ultimate strength of sand their connections. Suchloading should be assumedwith 1/3 of all normal characwind and imposed loading).

Load-bearing construction

For the purposes of this Gu‘load-bearing wall constructmasonry cross-wall construcomprising close centred timsteel section studs.

Alternative approac

5.4 Alternatively, for any does not fall into the classe

11 or for which the consequmay warrant particular examinvolved, the performance mrecommendations given in t

‘Guidance on Robustness a Accidental Actions’ dated J

‘Calibration of Proposed Remeeting Compliance with th

Building Regulation Part A3 Allott and Lomax proposalsNo. 205966.

Both of the above documenon the following ODPM webhttp://www.odpm.gov.uk

Diagram 24 Area at risk of collapse in the e ent of an acciden

REDUCING THE SENSITIVITY OF THE BUILDING TODISPROPORTIONATE COLLAPSE IN THE EVENT OF AN

http://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=260482REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=252984REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=257098REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=257098REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=253667REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=267193REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=267193REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=267214REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=267214REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=267214REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=267214REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=267214REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=267214REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=267193REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=267193REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=253667REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=257098REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=257098REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=252984REGhttp://www.thebuildingregs.com/RefDocs/CIS/Lookup.asp?AccessionNo=260482REG


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Diagram 24 Area at risk of collapse in the event of an acciden

See para 5.1d

A

Standards referred to


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A1/2

BS 187:1978

Specification for calcium silicate (sandlime andflintlime) bricks. AMD 5427 1987.

BS 1243:1978Specification for metal ties for cavity wallconstruction. AMD 3651 1981, AMD 4024 1982.(Withdrawn and superseded by BS EN 845-1:2003Specification for ancillary components for masonry.Ties, tension straps, hangers and brackets. AMD 14736 2003.)

BS 5080-1:1993Structural fixings in concrete and masonry.Method of test for tensile loading.

BS 5268-2:2002Structural use of timber. Code of practicefor permissible stress design, materials andworkmanship.

BS 5268-3:1998

Structural use of timber. Code of practice fortrussed rafter roofs.

BS 5628-1:1992Code of practice for use of masonry. Structuraluse of unreinforced masonry. AMD 7745 1993, AMD 13680 2002.(Withdrawn and superseded by BS 5628-1:2005Code of practice for the use of masonry. Structuraluse of reinforced masonry.)

BS 5628-2:2000Code of practice for use of masonry. Structuraluse of reinforced and prestressed masonry.(Withdrawn and superseded by BS 5628-2:2005Code of practice for the use of masonry. Structuraluse of reinforced and prestressed masonry.)

BS 5628-3:2001Code of practice for use of masonry. Materials

and components, design and workmanship.(Withdrawn and superseded by BS 5628-3:2005Code of practice for the use of masonry. Materialsand components, design and workmanship.)

BS 5950-1:2000Structural use of steelwork in building. Code of

BS 5950-5:1998Structural use of steelwork of practice for design of colgauge sections.

BS 6399-1:1996Loading for buildings. Codeand imposed loads. AMD 13

BS 6399-2:1997Loading for buildings. Codeloads. AMD 13392 2002, AM

BS 6399-3:1998Loading for buildings. Codeimposed roof loads. AMD 61996, AMD 9452 1997.

BS 8002:1994Code of practice for earth re AMD 8851 1995, AMD 1206 AMD 13386 2001.

BS 8004:1986

Code of practice for foundaBS 8103-1:1995Structural design of low-riseof practice for stability, site foundations and ground floo AMD 8980 1995.

BS 8103-2:1996Structural design of low-risepractice for masonry walls f(Superseded but remains currStructural design of low riseof practice for masonry walremains current.)

BS 8103-3:1996Structural design of low-risepractice for timber floors an

BS 8103-4:1995

Structural design of low-risepractice for suspended conc

BS 8110-1:1997Structural use of concrete. Cfor design and constructionAMD 13468 2002.

STANDARDS REFERRED TO

BS 8297:2000C d f ti f d i d i t ll ti

BS EN 845-2:2001S ifi ti f


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Code of practice for design and installationof non-loadbearing precast concrete cladding. AMD 11064 2000, AMD 13018 2000.

BS 8298:1994

Code of practice for design and installation ofnatural stone cladding and lining.

BS 8500-1:2002Concrete. Complementary British Standard toBS EN 206-1. Method of specifying and guidancefor the specifier. AMD 14639 2003.

BS 8500-2:2002Concrete. Complementary British Standard to

BS EN 206-1. Specification for constituentmaterials and concrete. AMD 14640 2003.

BS EN 197-1:2000Cement. Composition, specifications andconformity criteria for common elements. AMD 15209 2004.

BS EN 197-2:2000Cement. Conformity evaluation.

BS EN 771-1:2003Specification for masonry units. Clay masonryunits. AMD 15998 2005.

BS EN 771-2:2001Specification for masonry units. Calciumsilicate masonry units.(Withdrawn and superseded by BS EN 771-2:2003Specification for masonry units. Calcium silicatemasonry units. AMD 15974 2005.)

BS EN 771-3:2003Specification for masonry units. Aggregateconcrete masonry units (dense and light-weightaggregates).

BS EN 771-4:2001Specification for masonry units. Autoclavedaerated concrete masonry units.(Withdrawn and superseded by BS EN 771-4:2003Specification for masonry units. Autoclaved

aerated concrete masonry units. AMD 16000 2005.)

BS EN 771-5:2003Specification for masonry units. Manufacturedstone masonry units. AMD 15999 2005.

BS EN 771-6:2001

Specification for ancmasonry. Lintels.(Withdrawn and supeSpecification for anc

masonry. Lintels.)BS EN 845-3:2001Specification for ancilBed joint reinforcem(Withdrawn and supeSpecification for ancilBed joint reinforcem

BS EN 998-2:2002Specification for mor

Masonry mortar.(Withdrawn and supeSpecification for morMasonry mortar.)

BS EN 12620:2002 Aggregates for conc

DD 140-1:1986Wall ties. Method of

timber frame connec(Withdrawn and supeSpecification for ancilTies, tension straps, AMD 14736 2003.)

DD 140-2:1987Wall ties. Recommenties. AMD 7971 1994

A3BS 5628-1:1992Code of practice for use of unreinforced m AMD 13680 2002.(Partially supersededMethod of test for mcompressive strengthby BS 5628-1:2005 C

of masonry. StructuraBS 5950-1:2000Structural use of stepractice for design. R AMD 13199 2001.

BS 8110 1 1997

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