Agricultural drain

This is typically a 110mm PVC perforated pipe wrapped in geo-fabric (bidem) and laid in a trench filled with crushed 19 mm stone. The ends of this pipe should drain away from the structures or into an underground drainage system. Usually found where the natural flow of water (surface or underground) is blocked by a structure – house, retaining wall or perimeter wall.

Control / movement joint

A joint designed to permit relative movement of sections of a masonry structure or wall to occur without impairing the functional integrity of the structure or wall.

DB – Distribution Board

The DB board is the point from which electricity is distributed throughout into the house. Circuit breakers are linked to each circuit which supplies electricity to different areas of the house.   A mains switch and an earth leakage unit control the overall supply of power to the circuits.


National Building Regulations


National Home Builders Registration Council



A small section of timber member of minimum size 38 x 38mm, used to support a fixed ceiling. Usually fixed to the underside of the bottom truss chord or rafter.


Refers to the commercially known name of gypsum ceiling boards.Rhinoboard is a plasterboard and consists of an aerated or foamed gypsum core encased in, and firmly bonded to special paper liners.


Damp – Causes

• Roof leaks • Water penetrating brickwork; such as tops of parapet walls, window sills and around apertures (windows and doors) • Plumbing problems and leaks • Poor ventilation • Failed or absent damp proof courses (DPC) or damp proof membranes (DPM)

Damp – Condensation

Condensation is caused by excessive moisture that cannot escape from the inside of the property, such as newly build houses. Its not from water coming into the property.

Damp – Penetrating (Penetrating damp)

Penetrating damp is caused by roof, building or plumbing failure, resulting in water usually entering through the masonry work. Roof leaks affect roofs, ceilings, light fittings and walls. A watermark might appear, and grow if the water continues to enter.

Damp – Rising (Rising damp)

Rising damp is caused by water soaking up through porous materials into the floors and walls of the property (referred to as capillary action) and usually occurs in houses that don’t have a damp proof course (DPC) or the course has failed to work properly.


Patent defect

A patent defect is visible and obvious to all and the purchaser therefore buys the property with full knowledge of this defect.

Latent defect

A latent defect is more contentious, as the word implies, latent is ‘hidden’ and requires a trigger in order to activate it.


Hardwood Floors

A genuine wood floor consists of real planks of selected wood, the timber dried and treated to perfection before it is protected with a wear resistant lacquer.

Laminate Floors

Laminate floors should never be classified as a “Laminate wood floor” or even compared with a genuine wooden floor.

Laminate floors consist of a hard density fibre board (HDF) made out of saw dust or very fine wood fibres, adhesives and a décor paper (photograph of real wooden floors) as the top layer. The laminate boards are manufactured in very large sheets, then cut into smaller boards so they will look like real wood boards The décor paper is protected by an overlay that is wear resistant.

GLAZING REGULATIONS: – some general comments

Any window with a sill height of less than 500m must be glazed with safety glass.

Any pane of glass installed in a entrance door or door sidelight, or staircase or landing must be glazed with safety glass.

Any glass used in any bath enclosure or shower cubicle must be glazed with safety glazing material.



The development of fine cracks.

Cracking and crazing

Crazing can be caused by over trowelling a rich (high cement content) mix; or the use of sand with too much clay; or due to excessively quick drying (hot or windy conditions during the application).   Cracking may also develop later, after the plaster has hardened due to the use of poor quality sands or excessively thick layers of plaster.


Debonding is generally a result of inadequate preparation of the substrate – such as not cleaning dust or oily walls, or roughing up smooth surfaces, poor plastering techniques or the incorrect use, or lack of use, of suitable bonding agents.

Lack of Hardness

Lack of hardness can be caused by insufficient cement in the mix; use of sand with excessive fines; rewetting of mortar mix to prolong its use; rapid  drying out (the leads to incomplete hydration of the cement).



An intersection of roof surface and a part of the structure that rises above it.

Barge boards

A timber, fibre cement or PVC component fixed along the edges of a gable and covering the ends of the horizontal roof members.


Timber members of small section fixed parallel to the line of the eaves, at right angles to the truss rafters onto which roof tiles or slates are fixed.


The overhanging lower edge of a roof slope. Normally open or closed. Also referred to as a “soffit”.

Fascia board

A timber, fibre cement or PVC member that is fixed to the rafter ends, the wall face immediately below the eaves.


A strip of flexible impervious material that is used to exclude water from the junction between a roof covering and another part of the structure.


The part of the wall above the general level of the eaves at the end of a ridged roo,f or of a partially hipped roof which encloses the end of the pitched roof.


A section of timber member of minimum size 50 x 76mm, placed perpendicular to the rafter in order to support the roof sheeting materials.

Roof covering – minimum pitch of roof

Concrete and clay tiles – minimum 17° with underlay / minimum 26° without underlay.

Corrugated profile sheets (galvanised iron, fibre cement, polycarbonate, fibre glass) – minimum 11°.

Fibre cement slates – minimum 11° with underlay / minimum 17° without underlay.

Natural slates – minimum 20° with underlay / minimum 30° without underlay.

Metal tiles – minimum 11° with underlay / minimum 15° without underlay.

Long span sheet (metal and fibre cement) – minimum 3-5° depending on manufacturer’s specifications.

Thatch – 150mm thick minimum 45° / 300mm thick minimum 35°

Wall plate

A strip of timber, laid on top of walls to level the underside of rafters and trusses.


Expansive soils

Most clayey soils change in volume as their moisture content changes seasonally.  Shrinkage occurs mainly in the dry season and swelling during the wet season.  Damage to structures occurs when the potential expansiveness of the soil as not been properly taken into account during the design of the foundations.

Collapsible soils

These soils undergo a sudden decrease in volume when trigger events occur.  Such a trigger may be wetting under load, stress changes or even dynamic loading due to earthquakes.   Underlying dolomitic or limestone, which I easily eroded by acid water can cause sudden collapse (sinkholes) at the surface.



Light welded metal reinforcing used in walls. Looks like a ladder.


Damp proofing course – in walls


Damp proofing membrane – below floor slab concrete


Reinforced pre-cast concrete beam (normally 110 and 150mm wide x 75mm high) spanning across an opening in a wall such as external window, doors etch.

Walls – Cavity walls

Cavity walls are used in the Cape Condensation Area to combat condensation / damp by way of circulating air within the wall cavity and by providing a gap to prevent moisture seeping through the walls from the exterior brick leaf (“skin”) to the interior leaf. The cavity width must not exceed 110mm.

Walls – Collar jointed

Collar jointed walls are double skin brick walls with no cavity between the skins. Such walls are commonly used in the inland areas of South Africa.

Walls – Slip Joints

Slip joints must be installed between masonry walls and concrete slabs / beams to accommodate the unequal expansion coefficient of concrete and masonry. The slip joint should be capable of accommodating small movements of at least 1.5mm.  

Walls – Weep holes

Weep holes are formed in the outer leaf of cavity walls at intervals not exceeding 1000mm and immediately above the damp proof courses (DPC) by leaving perpend joints open for a height of approximately 50 mm. Some architects insert round holes to function as weep holes in place of the more traditional vertical perpend weep hole.


Well Point

A well point is a polyethylene pipe with a filtered end installed into a porous soil structure. The water is distributed by means of a surface mounted centrifugal pump.


A borehole is a shaft drilled to depths exceeding 20 metres with a large diameter casing allowing for the installation of a submersible pump to distribute the water.


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