Colinwell...Building On Tradition Since 1888

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Products - Masonry - Technical Information -

Introduction

Colinwell Architectural Masonry is a range of high quality concrete blocks which are available with accompanying special and accessory units. They have been developed and manufactured for use as pre-finished walling components to be built requiring no primary decorative treatment, or on-going maintenance. Colinwell Masonry allows great freedom of architectural expression and offers significant savings in the finished cost of walls when compared to facing brickwork or indeed common block with render/plaster and/or paint finishes.

Design Information

To reap the maximum benefit from designing with Colinwell Architectural Masonry, it is important to consider a number of criteria. Once these are understood and implemented, not only are the potential on-site economies substantial but creative versatility is also greatly increased.

Detailing Modular Design

It cannot be emphasised too strongly that planning within the size parameters of the block involves early consideration that later pays dividends not only in the economies it provides but also in the standard of finish. The most pleasing results will be obtained by the use of the range of special and accessory blocks available from Colinwell.

Bearing in mind that Colinwell Masonry is produced in two face sizes, i.e. metric modular
390 x 19Omm and metric 440 x 215mm, consideration should be given to the size of piers, panels between windows and the lengths of walls generally, which should be made to suit block modules. If this cannot be done then blocks may be cut to suit (see figs. 1 & 2 below). Attempts at lengthening the bond by putting in small pieces or widening perpends should be avoided at all costs.

An example of modular planning is in the case of a cavity wall of Architectural Masonry on the internal and external leaf. In fig 3 below, built in blocks of 400x20Omm co-ordinating face size, dimension A would be 1190mm and dimension B 99Omm. This means that C would equal 20Omm. Allowing for a 90mm thick outer leaf, the cavity width would be 110mm and there would be no cutting involved whatsoever.

Should the designer prefer to have a narrower cavity, then the coursing should be set out to full size units on the outer leaf thus requiring cutting on the inner leaf, the internal corner providing the facility for unobtrusively and neatly locating the cut lengths.

Door and window heights may be made to suit coursing by using a jumper course at floor level or at lintel height possibly continued around the building as a feature, as in fig 4 below.

Figs. 5 to 12 below, show the use of some of the Colinwell specials in a variety of bonding applications.

In advocating modular design, Colinwell realise that in essence, design recommendations often boil down to common sense, which in block design means thinking strictly in terms of the unit sizes and their relation to standard opening sizes. Colinwell Technical Representatives will be pleased to call and assist in the use of specials at each planning stage.

Detailing Lintels & Cills

Typical Colinwell lintel and cill details are illustrated, including suggested provision for the incorporation of cavity insulation boards.

Any combination of these examples can be used, providing the vertical d.p.c. lines up.

Composition & Manufacture

Blocks are manufactured from cement and graded crushed aggregate with an integral waterproofer and pigment, compacted under great pressure in moulds and cured with heat and moisture by low pressure steam. The blocks comply with the standards of BS 6073. Solid, Cellular and Hollow blocks all have a drying shrinkage of less than 0.06% and have a water absorption rate of less than 8%.

Shape

Blocks are rectangular with sharp arises. Solid blocks are unperforated. Cellular and Hollow blocks contain voids. Standard accessories and Specials available are: Half blocks, Quoins/Cavity Closers, Squints, Cills, Lintel, and Bond-beam. A number of standard specials are available and non-standard accessories and specials may be cut from standard units or manufactured to the designers individual requirements.

Applications

For use in the construction of external and internal load bearing and non-load bearing walls, including the inner and outer leaves of cavity walls. party walls, partition walls and boundary walls. They can be used below D.P.C.. They can also be used as reinforced masonry walls by the use of bed joint reinforcement or placing reinforced concrete in the cores of hollow blocks.

Maintenance

Masonry blockwork should not normally require cleaning.

Durability

The high quality of the blocks gives them an effective life far greater than normal concrete blocks. in addition, all blocks are waterproofed which besides aiding their resistance to rain helps them retain their fresh, clean appearance.

Surface Treatment

The blocks do not require any surface treatment. The appearance of external walls will improve with weathering. The blocks may be painted if required.

Distribution / Supply

Obtainable direct from the manufacturer - delivery to start about three weeks from receipt of written order and to an agreed programme. This is important because the diversity of sizes, shapes and colours manufactured does not allow for large stocks of any one type of block to be held

Packing

Blocks are packed in cubes with plastic covers and are delivered and off-loaded by crane truck on contractor's prepared level, dry site.

Handling & Storage

Care should be taken to avoid damage to surfaces; it is desirable that the blocks should be off-loaded and moved to laying position mechanically. They should also be protected from rain and dirt.

Laying

In normal conditions a 1:1:6 cement:lime:sand mortar is suitable. It is recommended that the mortar be waterproofed and tinted to compliment or contrast with the blocks colour. Any surplus mortar should be removed with a trowel immediately otherwise the face of the block may be permanently marked. The joints should be compacted with a jointing tool, taking care to give a consistent finish as possible. For best appearance we recommend pole jointing or raked jointing. Blocks should also be built at random from 3 cubes/bales in order to minimise any likelihood of a colour banding effect.

Ordering

When ordering from site by phone, please state type, size, colour, code and quantity required and give exact delivery location

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