F10 Brick and block walling

							F10   BRICK/BLOCK WALLING

05    FACING BRICKWORK _________
  -   Bricks: _________
      Special shapes: _________
  -   Mortar: As section Z21, mix: _________
  -   Joints: _________

10    SECOND HAND FACING BRICKWORK _________
  -   Bricks: Second hand bricks free from deleterious matter such as mortar, plaster,
      paint, bituminous materials and organic growths. Bricks to be sound, clean and
      reasonably free from cracks and chipped arrises.
      Supplier/source: _________
  -   Mortar: As section Z21, mix: _________
  -   Joints: _________

15    FACING BLOCKWORK _________
  -   Blocks: _________
      Minimum average compressive strength: ______ N/sq mm
      Work size(s): _________
      Finish/colour: _________
      Special shapes: _________
  -   Mortar: As section Z21, mix: _________
  -   Joints: _________

20    RECONSTRUCTED STONEWORK _________
  -   Walling type: _________
      Manufacturer and reference: _________
      Finish/colour: _________
      Special shapes: _________
  -   Mortar: As section Z21, mix: _________
  -   Joints: _________

30    COMMON BRICKWORK _________
  -   Bricks: Clay to BS 3921.
      Minimum average compressive strength: ______ N/sq mm
      Durability designation: ______
  -   Mortar: As section Z21, mix: _________

35    COMMON BLOCKWORK _________
  -   Blocks: Concrete to BS 6073:Part 1.
      Minimum average compressive strength: ______ N/sq mm
      Thermal resistance: Not less than ______ sq m degC/W at 3% moisture content.
      Work size(s): _________
      Special shapes: _________
  -   Mortar: As section Z21, mix: _________

40    ENGINEERING BRICKWORK _________
  -   Bricks: to BS 3921, Engineering Class B.
  -   Mortar: As section Z21, mix: 1:0-1/4:3
  -   Bond: English.
  -   Joints: Flush.

51    BASIC WORKMANSHIP:
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    -   Store bricks/blocks in stable stacks clear of the ground. Protect from inclement
        weather and keep clean and dry.
    -   Build walls in stretching half lap bond when not specified otherwise.
    -   Lay bricks/blocks on a full bed of mortar; do not furrow. Fill all cross joints and
        collar joints; do not tip and tail.
    -   Rack back when raising quoins and other advance work. Do not use toothing.
    -   Bring both leaves of cavity walls to the same level at
        - Every course containing rigid ties.
        - Every third tie course for double triangle/butterfly ties.
        - Courses in which lintels are to be bedded.
    -   Do not carry up any one leaf more than 1.5 m in one day unless permitted by the
        CA.

55      FACEWORK:
  -     Facework to start not less than 150 mm below finished level of external paving or
        soil.
    -   Select bricks/blocks with unchipped arrises. Cut with a masonry saw where cut
        edges will be exposed to view.
    -   Build walls in stretching half lap bond when not specified otherwise.
    -   Keep courses evenly spaced using gauge rods. Set out carefully to ensure
        satisfactory junctions and joints with adjoining or built-in elements and components.
    -   Protect against damage and disfigurement, particularly arrises of openings and
        corners.

60      ALTERATIONS/EXTENSIONS:
  -     Arrange brick courses to line up with existing work.
  -     Unless otherwise specified or agreed block bond new walls to existing by cutting
        pockets not less than 100 mm deep, the full thickness of the new wall, and:
        Brick to brick: 4 courses high at 8 course centres.
        Brick to block, block to brick or block to block: Every alternate block course.
        Bond new walling into pockets with all voids filled solid.
    -   Except where a straight vertical joint is specified, new and existing facework in the
        same plane to be tooth bonded together at every course to give a continuous
        appearance.
    -   Where new lintels or walling are to support existing structure, completely fill top
        joint with semidry mortar, hard packed and well rammed to ensure full load transfer
        after removal of temporary supports.

65      FIRE STOPPING: Fill joints around joist ends built into cavity walls with mortar to
        seal cavities from interior of building.

66      FIRE STOPPING: Ensure a tight fit between brickwork and cavity barriers to
        prevent fire and smoke penetration.

70      HOLES, RECESSES AND CHASES IN MASONRY: Comply with the relevant
        clause in section P31.

90      CRACKED BRICKS in existing facework to be cut out and replaced with matching
        bricks bedded in _________ cement: lime:sand _________ mortar, before
        repointing adjacent cracked joints as specified.

91      CRACKED JOINTS in existing facework which is not to be repointed: joints with
        cracks wider than ______ mm to be cut out to form a square recess of 15-20 mm
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     depth. Remove dust, lightly wet and neatly point in _________ cement: lime:sand
     mortar to match existing work.

95   REPOINTING: Where specified carefully rake out existing joints by hand to form a
     square recess of 15-20 mm depth. Remove dust, lightly wet and neatly point in
     _________ cement:lime: sand mortar to a __________________ profile in a
     continuous operation.
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F11     GLASS BLOCK WALLING

10      MORTAR JOINTED GLASS BLOCK WALLING _________
  -     Manufacturer and reference: _________
        Colour/Pattern: _________
        Size: _________
        Special shapes: _________
    -   Mortar: As section Z21, mix: _________
    -   Bond: _________
    -   Joints: _________
    -   Movement joint sealant: _________

20      STORAGE:
  -     Stack glass blocks and accessories clear of ground in a clean, cool, dry area.
        Prevent soiling, chipping and contamination.
    -   Store premixed mortar or cement and hydrated lime clear of ground in a dry,
        weatherproof, frost free area.
    -   Store sand on a firm, clean, free draining base. Cover to avoid contamination.

30      ADVERSE WEATHER:
  -     Do not use frozen materials. Do not lay glass blocks on frozen surfaces or when air
        temperature is at or below 5 degC and falling. Maintain temperature of the work
        above freezing until mortar has fully hardened.
    -   Adequately protect newly erected walling against rain, snow and sun. Cover when
        precipitation occurs and at the completion of each days work.
    -   Rake out and replace mortar damaged by frost and, where instructed, rebuild
        damaged work.

40      WORKMANSHIP GENERALLY:
  -     Coat sill with a thick application of bituminous emulsion paint. Allow to dry before
        placing first mortar bed.
    -   Mix mortar to a stiff, workable consistency.
    -   Lay glass blocks on a full even bed of mortar with a uniform joint width. Do not shell
        bed blocks or furrow mortar. Do not allow mortar to bridge movement joints.
    -   Lay patterned blocks aligned to give a consistent overall appearance.
    -   Keep courses level and in line and accurately plumb all wall faces, angles and
        features.
    -   Do not use steel tools to tap blocks into position.
    -   Install joint reinforcement, perimeter anchor and movement joint accessories as
        recommended by the glass block manufacturer/supplier.
    -   Prepare movement joints and apply sealant as section Z22.

50      MORTAR JOINTING:
  -     Finish joints neatly and consistently to the specified profile before final set.
  -     Remove surplus mortar from glass block faces as jointing proceeds using a clean
        sponge, cloth or bristle brush, and water.
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F20     NATURAL STONE RUBBLE WALLING

10      ___________________________ WALLING:
  -     Stone: __________________ thoroughly seasoned and free from cracks, vents,
        fissures or other defects which may adversely affect appearance, strength or
        durability. Range of sizes to be agreed.
        Finish: __________________ to match approved sample.
        Supplier: _________
    -   Mortar: As section Z21.
        Sand: Graded crushed stone, colour matched to approval.
        Mix: _________
    -   Joints: __________________ and finished as clause 40.
    -   Other requirements: _________

20      WORKMANSHIP GENERALLY:
  -     Cutting, dressing, laying and jointing of stone to be carried out by skilled masons.
        Provide evidence of previous experience and details of work previously carried out.
    -   Store stone clear of the ground, protect from inclement weather and keep dry.
    -   Lay stones on their natural bed on a full even bed of mortar with all joints filled and
        between 12-18 mm wide. Evenly distribute different shapes, sizes and colours
        throughout the face of the wall to give a consistent overall appearance and good
        bond with no long continuous vertical joints.
    -   Accurately plumb all wall faces, angles and features. Set out carefully to ensure
        satisfactory junctions and joints with adjoining or built-in elements and components.
    -   Prevent damage to stonework and keep clean during construction and until
        Practical Completion. Ensure that no mortar encroaches on face when laying. Turn
        back scaffolding boards at night and during heavy rain.

25      GROUND LEVEL: Facing stonework to start not less than 150 mm below finished
        level of external paving or soil except where shown otherwise.

30      CAVITY WALLS: Dress stones to give consistent thickness of leaf and ensure that
        specified cavity width is maintained.

35      BONDERS: In walls which are faced both sides build in bonding stones of a length
        two thirds the thickness of the wall, one to every square metre of each side of the
        wall and staggered.

40      JOINTING: Finish exposed joints neatly and consistently as the work proceeds.
        After the initial set has taken place, stipple joints with a stiff brush to remove
        laitance and give a coarse texture.

45      ADVERSE WEATHER:
  -     Do not lay stones when air temperature is at or below 3 degC, do not use frozen
        materials and do not lay on frozen surfaces.
    -   Adequately protect newly erected walling against rain and snow by covering when
        precipitation occurs and at the completion of each days work.
    -   Rake out and replace mortar damaged by frost and where instructed, rebuild
        damaged work.
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F30     ACCESSORIES/SUNDRY ITEMS FOR BRICK/BLOCK/ STONE WALLING

05      CAVITIES:
  -     Fill cavities with concrete up to 225 mm below ground level dpc. Concrete mix to
        BS 5328, Designated mix GEN1 or Standard mix ST2, high workability.
    -   Clean off surplus mortar from joints on cavity faces as the work proceeds. Keep
        cavities, ties and dpcs free from mortar and debris with laths or other suitable
        means.
    -   Leave perpends at 900 mm centres completely open in the brick course
        immediately above base of cavity, external openings and stepped dpcs. Provide not
        less than two weep holes over openings.

10      FULL FILL CAVITY INSULATION:
  -     Insulation: Mineral fibre batts to BS 6676:Part 1 or Agrément certified.
        Size to suit wall tie spacings, thickness: ___ mm.
        Manufacturer and reference: _________
    -   Store, handle and install to BS 6676:Part 2, clauses 4 and 5, ensuring no gaps in
        the insulation layer. Keep insulation dry and free from mortar and other debris.

12      PARTIAL FILL CAVITY INSULATION:
  -     Insulation: _________
        Size to suit wall tie spacings, thickness: ___ mm.
        Manufacturer and reference: _________
    -   Fix securely to inner leaf, ensuring that:
        - edges are not damaged and boards are close butted
        - joints between boards are kept clean, dry and free from mortar and other debris
        - the residual cavity is not blocked or bridged.
    -   Place and secure each course of insulation before building up inner leaf above
        level of previous course of insulation.

15      AIR BRICKS: To BS 493, Class 1, 200 x 75 mm, colour to match facing bricks, built
        in as the work proceeds.

17      VENTILATION DUCTS:
  -     Manufacturer and reference: _________
  -     Install across cavity, sloping away from inner leaf, bedding fully in mortar to seal
        cavity.

20      WALL TIES FOR CAVITIES IN MASONRY WALLS:
  -     To BS 1243, type: _________
        Material/finish: _________
        Size(s) to suit cavity width(s).

24      WALL TIES FOR BRICK FACING TO TIMBER FRAMES:
  -     Manufacturer and reference: _________
        Material/finish: _________

26      WALL TIES FOR _________
        Manufacturer and reference: _________
        Material/finish: _________
        Size(s): _________

28      FIXING TIES IN MASONRY CAVITY WALLS:
  -     Bed not less than 50 mm into bed joint of each leaf.
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    -   Slope slightly downwards towards outer leaf with drip centred in the cavity and
        pointing downwards. Do not bend ties to suit coursing.
    -   Evenly space at ___ mm horizontally, staggered in alternate courses, and at ___
        mm centres vertically, unless specified otherwise.
    -   Provide additional ties within 225 mm of reveals of unbonded openings _________

33      FIXING TIES IN MASONRY CAVITY WALLS WITH PARTIAL FILL CAVITY
        INSULATION:
    -   Bed not less than 50 mm into bed joint of each leaf.
    -   Slope downwards towards outer leaf with drip centred in the cavity and pointing
        downwards. Do not bend ties to suit coursing.
    -   Evenly space in horizontal and vertical rows (i.e. not staggered) at ___ mm centres
        horizontally, and ___ mm centres vertically, unless specified otherwise.
    -   Provide additional ties within 225 mm of reveals of unbonded openings _________

37      FIXING TIES IN MASONRY CLADDING TO TIMBER FRAMES:
  -     Fix ties securely to the timber frame with 50 mm x 11 gauge stainless steel annular
        ringed shank nails, and bed not less than 50 mm into bed joint of the masonry leaf.
        Do not bend ties to suit coursing.
    -   Slope downwards away from the timber frame.
    -   Space horizontally to suit stud centres and at ___ mm centres vertically, unless
        specified otherwise.
    -   Provide additional ties within 225 mm of sides of openings, at not more than 300
        mm centres vertically.
    -   Repair any damage to the breather membrane before erecting the masonry skin.

39      WALL STARTERS/CONNECTORS:
  -     Manufacturer and reference: _________
        Material and finish: _________
        Size(s):_________
    -   Sealant to external vertical joint: _________
        Colour: _________
        Prepare joint and apply sealant as section Z22.

42      JOINT REINFORCEMENT FOR _________
  -     Manufacturer and reference: _________
        Material: _________
        Width: 40-50 mm less in width than wall or leaf.
    -   Lay on an even bed of mortar in a continuous strip with 225 mm laps at joints and
        full laps at angles. Keep back 20 mm from face of external work, 12 mm back from
        face of internal work and finish mortar joint to normal thickness.

44      DAMP PROOF COURSE:
        Bitumen based to BS 6398, class ______
        Manufacturer and reference: _________

46      DAMP PROOF COURSE:
        Polyethylene to BS 6515.
        Manufacturer and reference: _________

48      DAMP PROOF COURSE:
        Manufacturer and reference: _________

52      FLEXIBLE SHEET CAVITY TRAYS:
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        Manufacturer and reference: _________

54      GAS RESISTANT DPCS/CAVITY TRAYS:
        Manufacturer and reference: _________

56      PREFORMED CAVITY TRAYS:
        Manufacturer: _________
        Type(s) and location(s)
        _________
        _________
        _________

58      PREFORMED DPC/CAVITY TRAY JUNCTION CLOAKS/STOP ENDS:
        Manufacturer: _________
        Type(s) and location(s)
        _________
        _________
        _________

62      JUNCTIONS/STOP ENDS FORMED IN SITU: Where preformed cloaks/stop ends
        are not specified form three dimensional changes of shape in dpcs and/or cavity
        trays carefully and neatly to ensure a fully watertight installation. Preformed
        cloaks/stop ends may be used in lieu, subject to approval.

66      INSTALLATION OF HORIZONTAL DPCS:
  -     Lay in continuous lengths on a full even bed of fresh mortar, with 100 mm laps at
        joints and full laps at angles.
    -   Width of dpc to be at least full width of masonry leaf. Do not cover edges of dpc
        with mortar.
    -   Where there are separate dpcs in each leaf of a cavity wall, ensure that edges do
        not project into the cavity.
    -   Immediately lay at least one further course of masonry on a thin even bed of fresh
        mortar. Keep finished joint thickness as close to normal as practicable.
    -   Ensure continuity of dpc with damp proof membrane at ground level.
    -   Ensure that dpcs at low level in external walls are never less than 150 mm above
        finished ground level.
    -   Sill dpcs to be in one piece and turned up at the back if the sill is in contact with any
        part of the inner leaf.
    -   Provide rigid support for dpc in cavity walls.

68      DPCS TO ____________
        Seal overlaps and junctions with _________

72      INSTALLATION OF GAS RESISTANT DPCS/CAVITY TRAYS:
  -     Overlap joints in dpc/cavity tray not less than 150 mm and heat seal to form a gas
        and watertight joint.
    -   Ensure that dpc/cavity tray overlaps damp proof membrane by not less than 150
        mm.

74      INSTALLATION OF VERTICAL DPCS
  -     Dpcs to be in one piece wherever possible; otherwise overlap by not less than 100
        mm with upper piece outermost.
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    -   Ensure that dpcs to jambs of openings fully lap behind cavity tray/lintel at head and
        over horizontal dpc at sill, project not less than 25 mm into cavity and are in full
        contact with frames.
    -   Fix jamb dpcs to back of timber frames which are to be built in, using galvanized
        clout nails or staples.

76      MOVEMENT JOINTS WITH SEALANT:
  -     Filler: _________
        Build in as the work proceeds ensuring no projections into cavities and correct
        depth of joint to receive sealant system.
    -   Sealant: _________
        Colour: _________
        Prepare joints and apply sealant as section Z22.

78      MOVEMENT JOINTS WITHOUT SEALANT:
        Filler: _________
        Build in as the work proceeds, completely filling the joint but without projecting into
        cavities.

82      PROPRIETARY PRECAST CONCRETE LINTELS:
        To BS 5977:Part 2.
        Manufacturer and reference: _________

84      PREFABRICATED STEEL LINTELS:
  -     To BS 5977:Part 2.
        Manufacturer and reference: _________
        Material/finish: _________
    -   Bed on mortar used for adjacent work with bearing of not less than 150 mm unless
        specified otherwise.

86      TILE SILLS:
  -     Plain clay tiles to BS 402:Part 1, size _________
        Manufacturer and reference: _________
    -   Lay two courses as detailed, to break joint, fully bedded in 1:¼:3 cement:lime:sand
        mortar as section Z21, with all joints filled and neatly finished flush.

88      FLUE LINING SYSTEM:
  -     Linings: Clay to BS 1181, type ______
        Bore: _________
        Manufacturer and reference: _________
        Accessories: _________
    -   Mortar: 1:2:8-9 cement:lime:sand as section Z21.
    -   Fully bed linings in mortar with socket or rebate uppermost and neatly finish joints
        flush, to provide an unrestricted flueway with smooth interior surfaces. Fill void
        between lining and surrounding work with mortar. Use correct starters, adapters,
        bends, etc.
    -   On completion, carry out a core ball test and smoke test in the presence of the CA.
        If any obstructions or leaks are revealed, submit for approval proposals for making
        good.

92      FLUE BLOCK SYSTEM:
  -     Manufacturer and reference: _________
        Components/accessories: _________
    -   Mortar: 1:4-5 cement:sand as section Z21.
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    -   Position blocks accurately and finish joints flush to ensure a smooth, unrestricted
        flueway. Use correct starter, offset and transfer blocks.
    -   Seal joints between blocks by _________
    -   On completion, carry out a core ball test and smoke test in the presence of the CA.
        If any obstructions or leaks are revealed, submit for approval proposals for making
        good.

94      FIREPLACE COMPONENTS:
        To BS 1251.
        Manufacturer: _________
        Components: _________

96      CHIMNEY POTS:
  -     Manufacturer and reference: _________
  -     Coping: _________
  -     Bed solid in mortar specified for chimney stack.
F       Masonry (continued)                                                           F


F31     PRECAST CONCRETE SILLS/LINTELS/COPINGS/FEATURES

05      EXTERNAL EXPOSED PRECAST _________
  -     Drawing reference(s): _________
  -     Concrete: To BS 5328, grade RC50 or C50.
  -     Reinforcement: As clause 25.
  -     Minimum nominal cover to reinforcement on exposed faces in the finished work: 35
        mm.
    -   Finish: _________
    -   Other requirements: _________

10      CONCEALED PRECAST LINTELS:
  -     Concrete: To BS 5328, Designated mix not less than RC30 or Designed mix not
        less than C30, maximum nominal size of aggregate 20 mm.
    -   Clear span      Section              Bearing              Reinforcement
        _______________________________________________________________
        Up to           150 mm deep          150 mm at            1 no. 12 mm mild
        900 mm          x width of           both ends            steel bar for
                                             wall                 wall thickness.
        _______________________________________________________________
        900 to          225 mm deep          225 mm at            1 no. 16 mm mild
        1800 mm         x width of           both ends            steel bar for
                                             wall                 each 105 mm of
                                                                  wall thickness.
        _______________________________________________________________
    -   Minimum nominal cover to reinforcement: 20 mm.
    -   For greater spans and/or greater than normal loadings see detailed drawings or
        obtain instructions.

20      MOULDS must be:
  -     Constructed accurately to give straight, square and true components.
  -     Maintained in clean, sound condition and inspected carefully for defects before
        each reuse.
    -   Constructed to prevent loss of grout.
    -   Designed to permit demoulding without damage to the components.
    -   Coated evenly with a suitable release agent, which must not be allowed to touch
        the reinforcement.

25      REINFORCEMENT:
  -     Type of reinforcement, unless otherwise specified: To BS 4449 and/or BS 4483, cut
        and bent to BS 4466.
    -   Fix accurately and securely. Tying wire must not encroach into the concrete cover.
        Cover spacers must not be used to concrete faces which will be exposed in the
        finished work.

30      CASTING AND CURING:
  -     Thoroughly compact concrete by vibration.
  -     Do not demould components prematurely.
  -     Prevent damage to immature components from movement, vibration, overloading,
        physical shock and rapid cooling.
    -   Ensure that components are protected from sun and drying winds until they are at
        least 5 days old.

35      FACING MIXES: Different mixes may be used for facing and backing provided:
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    -   The difference in cement content is not more than 80 kg/cu m.
    -   The thickness of the facing mix is at least 10 mm greater than the nominal
        maximum size of aggregate.
    -   Reinforcement is not less than 20 mm away from the junction between mixes.
    -   The backing mix and facing mix are placed and compacted within one hour of each
        other so that they are effectively monolithic.

40      LAYING:
  -     Unless specified otherwise, lay components on a full bed of mortar used for
        adjacent work.
    -   Leave bed joints to one piece sills/thresholds open except under end bearings. On
        completion point with mortar to match adjacent work.
    -   Faces which will be exposed to view in the finished work to be kept clean with no
        mortar encroachment.

45      SUPPORT OF EXISTING WORK: Where new lintels are to support existing
        structure, completely fill top joint with semidry mortar, hard packed and well
        rammed to ensure full load transfer after removal of temporary supports.