INTRODUCTION:

It is the dream of almost everyone to own a building. A building performs several functions one of them being a place to retire to after a hard day’s work. A place to engage in economic activities and; a place to nurture kids and to have a wonderful time with loved ones, friends and families. Recently, one major input that goes into building construction has experienced a significant price hike since the end of the #EndSars protest in Nigeria. I wish to use this opportunity to discuss a few things pertaining to cement in building construction.

OBJECTIVES:

The goal of this exercise is to

> Determine the quantity of cement that can construct a modest model 2-bedroom bungalow. (including external works)

> To measure the cost of the project when cement price was ₦2,500/50kg bag versus now that it’s ₦4,000/50kg bag.

> The percentage cost of the cement relative to the cost of the overall building project at ₦2,500/50kg bag and ₦4,000/50kg bag, respectively.

> To show the percentage contribution of each work package (stage) described below and some material items/class relative to the overall project cost.


Below is the 2D of the site layout showing the 2-bedroom apartment in 300m2 piece of land.

PROJECT DESCRIPTION:

To carry out this exercise, I have prepared a model 2-bedroom bungalow with a superficial floor area of 89m2. The features are.

1.     Two bedrooms (all en-suite)
2.     A living room
3.     A dining area
4.     Kitchen
5.     Lobby
6.     Entrance porch
7.     Back verandah.

This exercise included the cost of all external works(perimeter fence, sewage treatment system etc.) to arrive at the overall cost of this project. 

I will describe the contents of each stage (work package) of work in the project.

1.    Setting Out:

Here, a couple of bundles of pegs and 2’’x2’’x12’ timber is to be used to establish the location of the building on the land. The established profile will then serve as a guide for the excavation works and other works to be conduction the foundation. 

2.    Substructure:

This is the stage of work from excavation of trenches and pits to the damp proof course (DPC). Other items of work found in this stage are concrete works (strip foundation, pad footing, column stud and slab-on-grade/German floor), reinforcement works, block work, earth filling, etc.

3.    Sewage Treatment System:

This is actually stage 2b and supposed to be under the external works. However, I like to include it in the second stage so I can borrow earth from the pit to use for earth filling in the building if the earth is of good mechanical properties. Then the concrete works, block work and reinforcement works are all complete ensuring the sewage treatment system is completed to prevent it being a source of hazard on site.

4.    Blockwall, Column & Lintel:

This very stage comes immediately after the “German floor”. It ties together the external walls with a system of reinforced concrete beams(lintels) which also serve as a bridge for the openings (doors & windows).After the partitioning is done, anyone should be able to tell which function any space is meant for.

Good thread... Go on

Following earnestly

5.    Roof Beam & Parapet:

The concrete fascia popularly known as a parapet is a common feature in most buildings in Nigeria nowadays and for a good reason: an impressive aesthetic appeal. It typically comes in various shapes/design; cast in situ or precast. It’s typically connected to the roof beam on the perimeter(roof beam could occasionally run along interior walls) in the building.The typical items of work in this stage are the formwork, reinforcements, concrete and sometimes, electrical conduit pipes/accessories. The design used for this study is the flat type.

6.    Roofing Timber & Sheets:

This is another fundamental part of the building, providing protection against sunshine, rainfall, snow, storms etc. the skeleton is typically made of timber of varying sizes formed into an intricate system of trusses by the carpenters to withstand their own self weight and that of any imposed load (human, snow, water etc). They typically make the roofing sheets with aluminum, coated steel, clay tiles, PVC. They usually make roofing sheets from material(s) with an inherent capacity to resist the elements. Another important thing to consider when buying roofing sheets is to look at the gauge. The gauge is basically the thickness of the sheet measured in millimeters. Most commonly used are 0.45, 0.5 & 0.55 gauges. For this study, I have 0.45 gauge stone coated step tiles.

7.    Doors & Windows:

They typically make the doors from steel, wood/wood composite, aluminum. The steel doors are usually installed on the exterior (entrances & exits) while the wooden/composite doors find use within the house. The exterior doors will typically be 3 or 4 feet wide, 2 and half feet for the toilet doors and 3 feet for the rooms or other spaces in the building.They can also make the windows from a range of materials: wood, steel, aluminum & glass, etc. The aluminum and glass windows are really popular and can come as sliding or projected casement windows. The glass can be clear or tinted and to improve energy efficiency of the building, a double glazed (2 glasses with air void separating them) window can be used because of its impressive insulation properties. Architects can specify varying window sizes; however, the typical sizes in the market are 2 x 2 ft, 4 x 4 ft and 5 x 4 ft.

For this study, I've used aluminum projected casement windows.

I'm impressed. How do i get across to you?

Teaveapoet:
I'm impressed. How do i get across to you?

email frankitangltd@gmail.com

Nice idea

following closely

8.    Fixtures & Fittings:

A house wouldn’t be comfy and might even pose a hazard if certain features aren’t present. These are the furniture (wardrobes, kitchen cabinets), the steel handrails (wrought iron pre-coated with red-oxide), and the balustrade.

The other work packages which I will just mention but are very important parts of the building are

9.    Plumbing& Mechanical Installations
10.  Electrical Installations

11.    Floor Finishes:

The floor finishes a modest non-slip, unglazed ceramic tiles of 400 x 400mm square and 100mm high skirting at the edges of the walls.

12.     Wall Rendering:

The wall plastering is a 1:6 cement-sand mix design with a water-cement ratio of 0.5 and laid to a thickness of 12mm on interior and exterior walls without tiles.

13.    Ceiling Finishes:

The ceiling is a modest design POP ceiling board complete with cornish at the edges, complete with electrical spot lights and coated with emulsion paint.

14.     Paintings & Decorations:

 I made No allowance for wall screed hence emulsion paint was to be used on the interiors while texcoat paint was provided for the exterior walls. A cement-sand band window copings and run round the exterior perimeter of the building as specified in the architectural drawing. 

  15.    External Works:

These are items of work done outside the building. The items of work captured in this exercise are fence, double-swing gate, concrete pavement (3’’ thick), water tower (overhead water tank), water well, inspection chambers.

OBSERVATION:  

> Using a 1:3:6 concrete mix design for the cement, sand and gravel respectively; I calculated that the proposed building project will consume about 20 tons of cement. ·      

>  To arrive at the ultimate costs of the project for when the price of cement is ₦2,500/50kg and ₦4,000/50kg respectively, I’ve included the preliminaries sum, contingencies sum, consultation (Designs & Costing) and the management contractor’s (Supervision) fee.

From this exercise, I found the cost of the project with the modest finishes described above to be ₦9,256,463.60 and ₦10,016,553.60 respectively. It’s worthy of note that some other construction materials which don’t have Portland cement as one of their production inputs also experienced price hike. However, for this exercise I have used their recent prices in both cases. Some of these materials are the steel rods, P.O.P. cement, etc.   · 

>  At pre-EndSars price of ₦2,500/50kg bag, cement will make up about 11% of the overall project cost whereas it would be about 16% at ₦4,000/50kg bag.

The overall cost of this project would rise by about 8% from pre-Endsars cost due to the rise in the price of cement. For both cases, I think this is a really significant ratio for a single input into building construction.

> Finally, Cement is the single most cost intensive construction material regarding this project taking up about 10.8% at the pre-EndSars price of #2500/50kg bag.

I think this confirms mine and other peoples suspicion.

The most cost intensive stage in this project is the external works followed by the roofing (timber & covering), blockwall ( with columns & lintels) and the substructure with 19.9%, 8.8%, 8.1% and 8.0% respectively.

CONCLUSION:

I need to clearly state that these figures strictly apply to this model proposed building that will sit in a 300sq.m piece of land as shown in the site layout above. The material rates apply strictly to Enugu metro as the prices of these construction materials may vary in other states.

What this means is that the ratios may vary for another 2-bedroom bungalow built in another location outside Enugu. It might also vary for a 4-bedroom duplex or apartment blocks built within or outside Enugu state.



You can consult me for a cost estimate of your proposed building project or my services as a civil engineer on


Email: frankitangltd@gmail.com


You are most welcome to my TedTalk 

You have done excellently well bro

nairacountry:
You have done excellently well bro

Thank you. I'm glad you found it interesting.