dimensional blockwork

8/2/2019 Dimensional Blockwork

1/4

Design Considerations

Ff5(2-)

Uniclass EPIC L322 F611

CI/SfB

2003

Dimensional Co-ordination

DC3

High Street, Brandon, Suffolk IP27 0AX - Tel: 01842 810678 - Fax: 01842 81460 2 - E-mail: inf [email protected] - Website: w ww.li gnacite.co.ukMeadgate Works, Nazeing, Waltham Abbey, Essex EN9 2PD - Tel: 01992 464441 - Fax: 01992 445713

59

The Block ModuleWhere possible, a wall and all itsopenings should be designed t oaccommodate complete blocks,both vertically and horizontally.

Table 1 (see overleaf) is designedto simplify calculations of blockwork

dimensions for openings and corners.It gives the number of whole andhalf blocks (taking mortar joints intoaccount) for a given length of wall,or number of blocks high for a givenheight of wall. The table is usefulin planning horizontal and verticaldimensions, overall or betweenopenings, to suit and acknowledgethe block module.

Horizontal runsof blockworkWhere using only whole block

modules is difficult, cut blocks areused to adjust dimensions to suitparticular requirements. Their positionneeds to be carefully planned, keptto a minimum and positioned so asto be visually acceptable. Small bondZipper joints with a small bondoverlap should be avoided.

Keep cutting to a minimum andensure cut units are fully dry beforeincorporating into the work. Cutblocks can effloresce due to the

addition of water in the cuttingprocess.

Cutting blocks may also change theirappearance. We strongly recommendthat blocks are factory cut.

Corners

Corners are especially noticeablelocations and also places where cutblocks happen without pre-

planning. Quoin (L-shaped) blocksare recommended to maintainstrength and bonding around thecorner, and readily available as astandard size.

Alternatively, cut blocks can be usedas indicated. Small, quarter length,cut blocks, often seen at corners asan unplanned and cheap solution,are to be avoided especially in FacingMasonry applications.

The size of a block sets the scale and pattern of coursing on a wall which is bold anddominant - but which wi ll show up any mismatches between coursing and openings.

A w indow or door opening which does not relate to blockwork dimensions looks very

unsightly, wastes time and money on site, and may even be impossible to build.

Standard reveal blocks are alsoavailable to close the cavity at jambs

and at cavity wall ends. The relationshipbetween both leaves, the cavity andthe reveal should be pre-planned toavoid unnecessary cutting.

Wall Height sOverall wall heights can be adjustedby using half-height blocks at foot(starter blocks) or head, stringcourses, or by using plinth or eavesblocks. Various designs are availablein the Lignacite Ltd range or can bemade to suit design requirements.

Half bond joint using cut blocks

Quarter blocks to be avoided

Quoin block

Corner using cut blocks


2/4


3/4

Standard Joinery - Widt h

Typical Height Lintel Sub-ci llof item rebate height

(nominal) R H(mm) (mm) (mm)

750 W 65 150

900 W ++ ++

1050 W 140 75

1200 W 65 150

1350 W ++ ++

1500 W 140 75

1600 W 15 200

1650 W 65 150

2087* W 52 163

2100 W 65 150

2110* W 75 140

2137* W 102 113

Design Considerations

Ff5(2-)

Uniclass EPIC L322 F611

CI/SfB

2003

Dimensional Co-ordination

DC3

High Street, Brandon, Suffolk IP27 0AX - Tel: 01842 810678 - Fax: 018 42 81460 2 - E-mail: inf [email protected] - Website: ww w.lignacite.co.ukMeadgate Works, Nazeing, Waltham Abbey, Essex EN9 2PD - Tel: 01992 464441 - Fax: 01992 445713

61

Accommodating ServicesThe positioning of cable runs,switches and socket outlets needscareful planning. Wherever possible,it is desirable to conceal services inorder to avoid unsightly surface-mounted conduit.

This can be achieved by routingconduit within hollow blockwork,but requires a high degree of co-

ordination between blocklayer andelectrician. Trunking within skirtings,dados and architraves is another wayof concealing service runs. Switchesand plug sockets will always lookbetter if they are flush f itt ed.

Standard joinery Products

In many instances architects will planopenings to suit block dimensionsand then specify purpose-madewindows and doors to suit. However,more straightforward projects maydictate the use of standard joineryitems. These do not acknowledgeblock dimensions and can haveunfortunate visual and constructionalimplications.

With careful planning and the use ofsensibly sized cut blocks, sub-cillsand/or stooled lintels, even standardjoinery items can be incorporated ina visually intended manner.

The following tables provideinformation regarding typical joineryitem heights and widths andblockwork details to suit.

Services can be concealed intrunking systems integrated withindoor assemblies. This is a way ofconcentrating services such as light,power, communications, alarms, etc,in a system that includes accessoriessuch as flush faceplates.

W = Window, D = Door set or Door+sidelight++900mm and 135 mm high windows are100mm shorter than the equivalentblockwork module opening - * : Imperial

Standard Joinery - Heights

Typical Width Length L of cutof it em blocks over t o

(nominal) maint ain bond(mm) (mm)

410 W 415

450 W 435

488 W 302

600 W 336

630 W 347

635 W 448

650 W 350

750 W 386

780 D 340

856 D 422

860 W 423

900 DW 438

915 W 440

932 D 383

1085 W 371

1200 DW 400

1232 D 408

1275 D 418

1342 W 436

1350 D 440

1425 D 363

1500 D 378

1532 D 384

1638 W 400

1650 D 408

1699 W 417

1770 W 432

1800 DW 440

1832 D 369

1863 W 374

1950 D 388

2100 DW 413

2132 D 4182250 DW 440

2400 DW 396

W = Window, D = Door set or Door+sidelight


4/4

dimensional blockwork

Documents