PAS 70:2003 pdf download HD clay bricks — Guide to appearance and site measured dimensions and tolerance
1 Scope
This Publicly Available Specification gives guidance on assessing the appearance of facing bricks, and thedetermination of on-site measurements of work size dimensions, for all high density (HD) type clay bricks
as defined by BS EN 771-1.t includes a procedure for comparing sample panels with reference panels in order to assess theappearance acceptability of consignments of clay facing bricks. It is not intended to apply to common and
engineering HD type clay bricks.
t also provides a method of determining the overall dimensions of all clay bricks. The limits for thetolerance categories for the mean and range are those that apply to HD type clay bricks where themanufacturer’s declared work sizes are those traditionally known as British Standard dimensionsUK standard format clay bricks). If clay bricks are supplied with other work sizes, the limits for thesecategories will need to be calculated in accordance with BS EN 771-1
2 Normative references
The following referenced documents are indispensable for the application of this document. For datedreferences, only the edition cited applies. For undated references, the latest edition of the referenceddocument (including any amendments)applies.
BS 4035:1966, Specification for linear measuring instruments for use on building and civil engineeringconstructional works – Steel measuring tapes, steel bands and retractable steel pocket rules.BS EN 771-1:2003 Specification for masonry units – Part 1: Clay masonry units.
3 Terms and definitions
For the purpose of this Publicly Available Specification, the following terms and definitions apply.3.1brickworkmasonry of bricks bonded and solidly put together with mortarBS 6100-5.1:1992
3.2
HD (high density) clay brick
clay masonry unit with a high gross dry density for use in unprotected masonry as well as in protected
masonry
BS EN 771-1:2003 with NationalAnnex
NOTEThese relate most closely to facing units in BS 6100-5.3 although, as the BS EN is performance related,the requirements arewritten in terms of durability rather than appearance.
3.3
brick
masonry unit that does not exceed 338 mm in length, 225 mm in width or 113 mm in heightBS 6100-5.3:1984]
3.4
facing unitmasonry unit specially made or selected to give an attractive appearanceBS 6100-5.3:19841
8.5
common unitmasonry unit suitable for general construction work, with no special claim to give an attractive appearanceBS 6100-5.3:1984
3.6
engineering brickbrick sized fired-clay unit that has a dense and strong semi-vitreous body, that conforms to defined limitsfor water absorption and compressive strength
BS 6100-5.3:1984]
3.7
recessed joint
mortar joint with its face finished back from the arrises and face of the adjacent masonry units
3.8
flush joint
mortar joint with its face finished level with the face of adjacent masonry units
BS 6100-5.1:1992]
3.9
reference panel
trial panel built as brickwork and usually constructed at the start of a project for the purpose ofestablishing the visual characteristics of the brick, which is to be representative of the appearance of thebrick to be used in the executed work
3.10
sample panel
panel of brickwork or mortarless laid bricks erected adjoining the reference panel during the ongoingproject works for the purpose of assessing the visual characteristics of bricks taken from subsequent projecdeliveries, to ensure a consistency of appearance in the executed work