Mortars

Far too little attention is paid to the correct and consistent mixing of mortars on site and this oftern adversely affects the quality or appearance of the brickwork. The use of gauge boxes, or other forms of accurate measurement, is far preferable to the casual selection of materials by a shovel. Ready mixed lime/sand for mortar is an advantage in mortar preparation.

Cement

Sand mortar mix is generally most suitable for use with Geerco Bricks under normal conditions. This mix has the advantage of setting quite quickly and being used throughout all types of brick and blockwork in a normal construction. This use of the same mix throughout a site enables the preparation, control and use of the mortar to be consistent. Whilst lime provides ideal workability in a mortar, some other additives, used correctly, can attain the same results.

Plastering and Rendering

Because of the decorative appearance of Geerco bricks, it is not normally necessary to apply rendering or plaster. However, both forms of treatment can quite satisfactorily be applied to Geerco brick work in the same manner as to other of brick.

The brickwork should be clean, free from oil, grease or other adhesion.

Wall Ties

Wall ties should preferabley be of the wire butterfly type and be kept well clear of droppings to avoid the carriage of moisture between brick leaves. The spacing of wall ties will need to be in accordance with building regulation requirements or the instructions of the enforcing authority

Laying

Geerco Bricks should be in a reasonably dry condition when laid and will then provide adequate suction for adhesion between bricks and mortar. They should never be hosed or soaked neither should they be subjected to prolonged stacking on site. In very dry conditions the adhesion can be assisted by quick dipping of the the brick in water or preferable by increasing the water content of the mortar.

Design & Structural

Vertical Movement Joints

The insertion of movement joints can be quite simple and inexpensive, need not be unsightly but can be used as a feature and should be inserted at intervals of approximately 7-5 m to 9 m. They can be adjusted in their spacing, or position, to suit door and window openings or changes in wall height and direction, which are points where movement stresses tend to coverage. The following points should be observed when constructing movement joints

Straight (Rigid or Flexible) Joint

From brickwork into panels separated by 10-12 mm vertical space. Insert a membrance of bitumous felt, polythene or similar, laying back about 12 mm from face. Seal joints with mastic, or other sealant. Panels can still be tied together by method not restricting required movement.

Toothed Joint

Insert separating membrance of bitumous felt, polythene or similar as brickwork progresses. It should follow the joint pattern as shown, and should separate one of the adjoining bricks from the mortar.