Plaster is used to decorate external wall surfaces.
This surfaces have smooth facades which should be weather resistant.
Paint or resin coats can be used as a final finish to the wall plaster.
In the finishing of buildings, the externals should have appealing but durable aesthetics.
Features on plaster work can be molded to form beautiful patterns.
This features can be arches, rectangular or circular shapes on window or door openings.
Other areas can be on gable walls or even the plain wall surfaces.
The features on external plastered wall surfaces should be done when major works on site are complete.
This is because they are delicate in nature.
They should dry adequately before any other finishes are applied including paint works.
The thickness should not exceed two inches.
If it does exceed then a mesh must be used.
This nailed and inserted in between the two layers of one each thick plaster mould.
This shapes should also not carry any loads or have cladding anchored on them.
The procedure of forming features is to first choose the place to fix them.
To make an arched window mould, a form work is erected around the window.
This form work is attached to the edge of the window opening.
It is fixed by supporting the frame work using wedges and short posts spanning the length and width of the window.
This forms should not be nailed onto the window opening.
The reason is that, when removing the nails, the shapes would be damaged.
The forms should be one greater than the plastered wall surface.
The width of the molding to be shaped should be about two inches wide.
Strong cement plaster is mixed and is applied slowly around the arched window.
The process is done in three coats.
Each coat is allowed to dry for at least forty five minutes.
A wooden float is used to rub and smoothen using up right strokes.
Once the mold is finished, the excess plaster is removed carefully.
After four days of drying the form work is removed.
This is then allowed to dry for one week.
Painting or resin coats can then be applied on them.