How To Construct Concrete Facial (Parapet) For Roof






July 27th, 2014 by 'Kayode

This article is to open your eyes to multiple options you have in concrete facial (parapet).

Concrete facial (parapet) is used in modern day buildings to substitute facial boards which is common in older buildings.

Determine the type of design you wish to use, what we see mostly is concrete facial with one or two steps at the base and top with curve at the center connecting the two ends.

But concrete can be molded to any shape desirable, so the need for the designers of building to come up with other interesting designs apart from what everybody is used to. Aside having curved sides, you can also have beveled/triangular shape and other kinds of shapes.

Determine the numbers of planks and other materials needed. Planks are in length of 3.6m or 12ft, since the facial is placed round the perimeter of the building, calculate the perimeter, multiply by 3 ,then divide by 3.6m or 12 feet to get the total numbers of planks of 1by12 you will need to order for in the market.
You need planks as base for the extended portion of the concrete facial, some planks will be cut to sizes as shown in pictures to form the external surface portion which is mostly in curves.

Plywood will have to be laid along the external surface as shown in pictures to give a smooth finish to the concrete externally. The shape of the external surface is determined by your design so your design will show how you will cut the plan that will form and support the external surface, just as earlier said the curved edge can be replaced with any design you wish to have which will also makes it unique.

The best approach in constructing concrete facial is as explained further down page .

Leave one course of block work to accommodate a beam which also serves as the roof beam, this traditional roof beam is now added an extension of 8mm rods jotting out from each ring of the reinforcements/iron rods. The extensions are bent to follow shapes of the design of the external surface of the concrete facial as shown. Get the planks that will support the concrete on both sides, also extends a quarter rod from the beams to the top of the beam beyond the surface, this will be used to hold the timber coming on top later for the roof.

Note that the extended rod comes out from the center of the beam, the iron rods are needed to help hold the concrete and also stabilizes the building as is connected to the roof also.

Plank is cut at intervals to help give the perfect shape needed, the cutting is mostly done at the sawmill when you have given out your specifications.

Also make sure there are columns at the edge of the wall carrying and transferring the weight from roof to the ground even if it’s just a bungalow of only ground floor.

To form steps at the top and base of the external surface curve, the conventional method is to place 2by2 wood at the edges to form the steps , but you can also cut the wood to shape, cover the surface with plywood to achieve a better result.


Aremu 'Kayode
Paddy Eng. Consultant
2348055767231
2348034646220

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