HOW TO CALCULATE THE MATERIALS REQUIRED FOR A KNOWN VOLUME OF CONCRETE

Material estimation includes sand, cement, coarse aggregate and steel for a particular mix design. Let us consider a mix design of 1:2:4 for our estimation practice. The dry volume of total materials required is considered as 1.54 times the wet volume of concrete. This is due to the voids that are present in sand and aggregates in dry stage. Therefore, for our calculation, we will consider the total volume of materials required as 1.54m³ for 1m³ of wet concrete.

a) Bags of cement required:

Volume of cement required for 1m³ of Concrete = (1 x 1.54) / (1 + 2 + 4) = 0.22m³

But the volume of one bag of cement = 0.0347m³;

Therefore, the number of bags of cement = 0.22 / 0.0347 = 6.34 bags of cement; Say, 7 bags.

b) Volume of Sand required:

Volume of sand required = (2 x 1.54) / (1 + 2 + 4) = 0.44m³ of sand.

c) Volume of Coarse Aggregate Required

Volume of Coarse Aggregate = (4 x 1.54) / (1 + 2 + 4) = 0.88m³.

d) Estimation of Reinforced Steel:

Quantity of steel required depends on components of structure, i.e. slabs, beams, columns, foundations, roads etc. To estimate the steel required, there are two methods:

The first method is, when we have the drawings available, we can calculate the total weight of steel required, and dividing it by the total volume of concrete for the different components.

This will give us the weight of reinforcement steel per cubic meter of concrete for the different components.

The second method is assuming the percentage of reinforcement for different components.

The following are the percentages of reinforcement steels generally required for the different components. Its values can vary from structure to structure, and can be assumed from past experiences of similar structure.

For slabs = 1.0% of concrete volume.

For Beam = 2% concrete volume.

For column = 2.5% of concrete volume.

For Reinforced concrete roads = 0.6% concrete volume.

CAUSES OF BUILDING COLLAPSE

Collapse of buildings is not new to Nigeria, neither is it only peculiar to Nigeria. Nevertheless, that will not stop us from taking critical look at the situation and finding a solution to it.

Collapse though can happen to any kind of building, but the casualties that usually follow the collapse of multi-storey buildings can be so terrible.

The collapse of storied buildings in Nigeria usually goes along with it, casualties which can be more up to 20.

But what really motivates multi-storey buildings?

Multistorey buildings are either built because of social status. There are places you get to, and all you would see are very high-rise buildings; so you wouldn’t want your building to be unnoticeable amongst them.

Commercial viability of a location can also make more people to build storied structures in the area because more people would clamour for space in the area.

Some locations are routes to a lot of places; so, high vehicular and human traffic is usually associated with such places, hence more commercial activities, and thus, the need for high-rise buildings.

There is always a tendency of man habiting very close to water because of the opportunity of controlling the waterways which can give opportunity for inter trade between nations. Their closeness to water naturally gave room for shipping ports in these areas, shipping port in turn promotes commercial activities, and commercial activities naturally generates heavy human traffic, and human being requires shelter for himself, his goods and services. So, buildings spring up in these places, and this brings about competition for the very few available spaces. Hence to meet with the demand, designers and building contractors will have to settle for multi-storey buildings because of the increasing unending economic value of these places.

Now, the soils in these areas are sandy and loose soil. They are not strong or compacted soils. Hence, the need for building construction professionals is usually high here. For most of these buildings, they dig long and strong piles foundation. However some few of these buildings still collapse.

 So, what causes the collapse of these buildings?

(1) The first problem is boycotting the professionals -

This issue had been over flogged both in print media and electronic media but it still persists. There is also a problem of egghead professionals that believe they know everything and are not ready to take advice from a colleague. There are known cases like that, which has turned awry.

(2) Contractors cutting corners -

Contractors trying to make gains at the expense of the lives of the users of the building are another problem that has to be tackled. There should be a check from policy makers to make sure specification is thoroughly adhered to by contractors.

(3) Human activities on building -

As insignificant as the human weight may seem to be; the moving up and down of the live loads and the dead load contributes over time in no small measure in wearing down the building. It will take long time though, but houses also expire, and in the case of the types of buildings we have in Nigeria, their lifespan is shorter than those in the civilized world.

(4) Inadequate foundation -

This is the most important part of a building. Unfortunately, a lot of people are not giving adequate attention to this and it is causing more problems. A registered Structural Engineer is very important to you if you are planning on building a strong and solid multi-storey building.

(5) Ageing Building -

Many do not know that buildings also have their life span. Most of the buildings in Lagos Mainland have spent 25 years and above; despite that, they are of shallow foundation and very low quality materials are used for them. As you lay your bed, so you shall lie on it. If you use low quality materials in building, and thereby thinking that you will cut cost, then also be expecting to park out of that building very soon.

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ADVANTAGES OF ENGINE MOULDED BLOCKS OVER HAND MOULDED BLOCKS

Many people mould blocks onsite, using masons and labour to do the job, and claims it is cheaper but I don’t think so when you consider the advantages the engine moulded blocks has over hand-moulded.

(1) Engine moulded blocks compacts better than hand moulded blocks because of the greater pressure that is being applied by the engine. The sands are better compacted and give better products than the hand-moulded blocks.

(2) The engine-moulded blocks are faster to produce; therefore a deal of time is saved which helps in reducing the general project construction time.

(3) The engine-moulded blocks are also finished with a smoother surface which helps the bricklayer during laying and gives the building a nice look.

(4) The engine moulded blocks process helps to reduce theft. Imagine you having a limited time to monitor the forming of the blocks with engine, what would have taken one month to do will be done in three days or less depending on the capacity of the engine. You can take less time to monitor the materials used like cement, quantities of sand bought, and you can monitor the mix ratio/quality unlike the hand-moulded that will delay and create room for the labourers to steal the materials.

(5) Is easier to monitor the forming process as well

(6) The engine-moulded blocks with same mixture ratio as the hand-moulded blocks would be stronger due to better compacting.

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WAYS OF FINANCING YOUR BUILDING PROJECTS. NO. 1. PERSONAL SAVINGS

In order to get a loan to build a house, you must understand that collateral is always needed, but not everybody is comfortable with this arrangement. What becomes of you if you are unable to pay back?

Now, let us talk about all the means available for you through which you can finance your building project, and then, you can choose the one that is most suitable for you.

PERSONAL SAVINGS

This is by far the most popular method people are using to get their house built. There is no fear of creditors knocking on your door and it gives a lot of rest of mind. Honestly, no matter how small your salary is, you can build a house if you set your mind towards it. There is always a case of you saving from whatever your income is. Study has showed that 30% of the moderate level of what we get monthly goes to buying very unimportant goods and junks. So you can cut unnecessary costly foods in costly restaurants.

Sit down, make an inventory of wasteful spending, and start saving 20% only of your income, no matter how small. In 2 years time, you would start building a house of your own. Whatever you were able to save would be enough to start your house.

Personal savings amongst others is the first option if you want to acquire a land and building a house.

ADVANTAGES

i. There are no debts to pay no matter the turn of things.

ii. You have rest of mind, since there are no creditors coming to knock on your door.

iii. It is healthy at the long run. When your mind is free of fear, you are most likely to live a healthier life and avoid hypertension.

iv. It gives you room to channel your earnings towards something valuable and gives you more responsibility.

DISADVANTAGES

i. It may take a long time to achieve your dream

ii. It bites on your income and may moderate your style of living

iii. Staying for too long might make somebody to loose interest altogether and abandon the project.

iv. There is always fear of families of (Omo Onile) Landowners rising up to lay dubious claim on your land especially when the seller is dead, because of long time of building.

v. There is always probability that the savings might be converted for other uses.

vi. Inflation on cost of materials and labour may also be seriously catching in.

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WAYS OF FINANCING YOUR BUILDING PROJECTS. NO. 2. WORKPLACE MORTGAGE AND LOANS

In order to get a loan to build a house, you must understand that collateral is always needed, but not everybody is comfortable with this arrangement. What becomes of you if you are unable to pay back?

Now, let us talk about all the means available for you through which you can finance your building project, and then, you can choose the one that is most suitable for you.

WORKPLACE MORTGAGE AND LOANS

This is most attractive to workers that are planning to invest in Real Estate. Though it is mostly used for personal buildings, but in giving you a honest advice, it would be better for you as a young man or woman to build the house, then rent out and let the building pay back for the loan back as you collect the rents. Then you can use the dividends to finance another project.

The National Housing Fund remains the most attractive leeway for those who desire to build with loans, especially the civil servants. It is designed by the government to aid the Federal Mortgage Bank of Nigeria, with less bureaucracy unlike before, and it offers presently a maximum of N5m at an interest rate of 6%, and a whopping 25 years of repayment tenor. This fund can be joined through any of the mortgage banks in Nigeria.

ADVANTAGES

i. Fast completion of building

ii. The paying back period is long and it is deducted automatically from your monthly income without you feeling the pinch because it is usually very small.

iii. The interest rate is very low.

iv. If you understand real estate business, this opportunity can turn you into a millionaire.

DISADVANTAGES

i. You are indebted for a very long time.

ii. Interest rates, no matter how small, will still eat into your pocket.

iii. Sudden severance of your job may leave you in the cold against your creditors. What if you were unable to get another job?

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WAYS OF FINANCING YOUR BUILDING PROJECTS. NO. 3. THRIFTS AND COOPERATIVES’ HOUSING SCHEMES

In order to get a loan to build a house, you must understand that collateral is always needed, but not everybody is comfortable with this arrangement. What becomes of you if you are unable to pay back?

Now, let us talk about all the means available for you through which you can finance your building project, and then, you can choose the one that is most suitable for you.

THRIFTS AND COOPERATIVES’ HOUSING SCHEMES

This method is becoming more popular among the young workforce and a lot of cooperative housing schemes are springing out daily. It employs the same old mode of operation, only that in this case, you are expected to own a home at the end of it.

All members pool resources together to build houses for each member in areas of choice. This is an alternative to mortgage for the low income earners, who makes monthly minimal contribution overtime.

ADVANTAGES

i. Just as in mortgage loans, fast completion because of readily available funds.

ii. At times members purchase large expanse of land and divide between members which is more comparatively cheap. They get professionals to do the projects in large volume, and the professionals in turn charge less because of large numbers of jobs. Housing cost can be reduced by 25% with this method.

iii. Encourages other mutual benefits and promote friendliness.

DISADVANTAGES

i. It definitely goes without saying that the cooperative society of choice must be well researched and thoroughly investigated to ascertain the commitment and integrity of its members. Some members can decide to default and this may lead to the collapse of the cooperative club.

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THE IMPORTANCE OF GERMAN-FLOOR OR OVERSITE CONCRETE IN A BUILDING

Question: I’m trying to put up a two-flat Bungalow in Lagos. It is already at the foundation stage. I was advised to run German floor after foundation, but considering quotations I’ve got so far, it seems a bit expensive. Another person advised that I should rather spend such money to set blocks and do flooring later. My inquiry into other projects within the site revealed that not everybody did German floor after their foundation. Please, what is the importance of German floor?

-               - Victor.

Answer: Thank you Victor.

The importance of german floor or oversite concrete in a building can’t be overemphasized. There had been a lot of arguments on whether to use a german floor for building projects or not. I have also built too without a german floor in exceptional cases, but this is not the best practice.

On a very solid soil, most people tend to forgo german floor because of the cost of concrete, especially on a one-floor bungalow. However, you must not build in a waterlogged place or area susceptible to heavy settlement without doing german floor.

In other words, german floor is important and very necessary, if you can afford it, even on solid and non-problematic areas.

These are the importance:

(1) German floor stops water from percolating from the soil into the building. It reduces the movement of water from getting to the walls and floor, which may cause damp and result in algae growth around your walls. If the german floor is used with a membrane or nylon or cellophane spread to cover the floor before casting it will reduce water getting up greatly.

(2) The german floor is also a part of foundation; it should be seen as one of the structural elements that make your house to stand. Loads transmitted from the building are also received by the german floor before being transmitted to the foundation. In a raft foundation, it is inevitable to have german floor because you have to blend it with the strips coming from the foundation base, in order to form a mass of concrete that is monolithic and helps to stabilize the building.

(3) For stability. As was mentioned earlier, it is a part of the foundation, and it forms a stable base for both live loads and dead loads in the building. You should be confident while stepping on the floor by making sure you have a solid floor which can also sustain earth tremors or vibrations from machines in and around the building.

(4) When there is a movement in the soil, the german floor helps to redistribute the forces on the building, and spread same around the floor easily which may also help to sustain the building from collapsing.

(5) When there is cracking on the block wall, (for non major cracks) the german floor can serve as a breaking point that will stop blocks from extending crack lines into the other parts of the building; that is, if the crack is up, then it may not extend beyond the german floor towards the foundation, and if the minor crack is from blocks under the german floor, it may not extend beyond it except there is a major defect in foundation due to settlements or improper foundation.

(6) A well done german floor also helps in determining and correcting problems associated with levels when construction is on.

Before your builder cast the german concrete, you have to ask him to take the level of the building round to achieve an even plane which will make your house to come out better during construction.

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ADVANTAGES OF ALUMINUM ROOFING OVER OTHER TYPES OF ROOFING

Though costly, the trend these days is to use aluminum roof to cover your house because of its advantages.

1. It is light.
Aluminum is comparatively very light .Conveying from one point to the other is easy. And it doesn’t add much weight to the building structure. The structural effect of it on a building is virtually nonexistent.

2, It is clean.
The roof is also very clean and easy to handle, you don’t need to wash or do some extra treatment on it.

3, It is not harmful.
Due to shortage of tap water, A lot of Nigerians drink rainwater dropped from the roof. For an asbestos roof, study has shown that drinking water from it may cause cancer, and for common zinc, it easily corrodes and particles from it also go along with the fetched water. But this is not so with aluminum because of its clean nature.

4, It fits perfectly well to your building.
Aluminum in the factories are rolled like toilet rolls it is when you measure the span of your building roof trusses that the aluminum is cut into the size and length of your roof.

5, It doesn’t leak easily.
Except during the process of installation, it is only when the roof is damaged by nails or others that you may experience leakage; but this can also be easily corrected.

6, It is not corrosive
Aluminum doesn’t corrode or rust, hence it is good when you are thinking of long term benefits.

7,It lasts long
Because of its non corrosive nature and ease of dismantling it lasts longer than most of other roofing materials.

8, It is reusable
Due to changes in house plans and taste, some buildings are daily demolished to pave way for modern and new buildings. But the aluminum roofs can always be carted away to be reused somewhere else or sold.

9, Ease of dismantling.
You can easily dismantle the roof and use it elsewhere without damaging it.

10, Ease of installation.
Among the roofing materials, aluminum roof is the easiest to install. Just cut to roof trusses length and fix together with nails at 1200mm centers e.t.c.

11, It is aesthetically more pleasing.
It is most beautiful among the roofing materials we have, especially when you are looking for a colour that will blend easily with paints on walls and the environment.

12, It can be of any colour.
The roof can be coated to any suitable colour you might like to have.

13, It is malleable.
Under certain conditions, it can be bent to form some desired shapes. Eg., arcs, curves e.t.c

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HOW TO MAKE MONEY AS A SUPPLIER IN THE BUILDING INDUSTRY

The opportunity available to you in the building industry is limitless.
Suppliers are making a lot of money now than ever.
The steps you have to take to become one may actually be the easiest.
Depending on your target, you may not necessarily have the money before you begin to market a product and end up supplying same.
Most of the building materials company will be glad to have you as an individual with no money in your pocket, but with zeal, determination, and agility to market their products. A lot of them give fantastic commissions for every successful purchase made by your client.
To do this, you only need to walk into some of these companies and register as a marketer for them. They will gladly give you guidelines and steps to take in order to make sure you are successful.
A lot of people are already doing this, so it is not a new thing; and if people can be there and still doing it, then, that means they are getting paid for their efforts.
Quite a few people have met me on site to introduce one product or the other to me.
But what you need is consistency, loyalty to the company you are marketing, know their products and be ready to walk, make phone calls, and do some trekking.
In this information age, most of the building construction firms you need are already on the internet, so you can email them, get their addresses, and also call. You have to invest your time and money; and also be consistent.
The easiest method you can get a supply is through referral. When somebody that knows somebody somewhere is referring you, the person is putting trust and reputation on you; and people tend to give contracts to referred persons by someone close to them.
The list is endless amongst suppliers in the building industry. They are
-Wood suppliers
-Iron rods
-Cement
-Sand
-Granite
-Marble and Tiles
-Electrical fittings/cables
-Plumbing fittings
-Doors
-Aluminum products
-Alucobond
-Furniture
-Burglary proof/gates
-Ceiling materials- P.O.P, asbestos slate e.t.c
-Roofing materials- aluminum,
-Paints
-Interlocking stones- laying and supplies
-Wire or Cables e.t.c

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HOW TO START A CONSTRUCTION COMPANY WITHOUT A DIME.

We sit on and around wonderful opportunities that can turn our lives around and make us the millionaires we eagerly wish for. Quoting Samson Makinwa, chairman of Techo Quip Ltd, on the Wealth Platform of Vol no 3/09 the headline reads “it is easy to make money in Nigeria. There is money all over the streets, yet most people cannot see it”, I can’t but agree with these sayings.
The first thing you need to have before dabbling into the construction industry is the will, you need the determination to do it, and you must be patient; because it is unlike the other industries where you may have jobs to do throughout the whole year. Though your company could grow up to actually achieve that, but for a beginner, business may not come even for some months before the breakthrough.
The second step is to learn the trade. You can make friends with a contractor or a professional in the field with vast experience that you can understudy and learn from. He may actually be your friend, or a pure professional that you may have to contact and arrange a time to work for him in order to have an idea about how things are run.
The next step after some few months of training or understudying your mentor should be for you to start thinking of registering a company.  However, since you are starting with no money down, I will advise you liaise with an established and registered company to work with and write proposals, with this you will make an agreement with the business owner on profit sharing before you can finally stand on your own with your name, and organise your office.
What you should naturally do is to get an office, but your home address could be your office address, or you use a friend’s office temporarily.
Without the job, all the facilities you are running after would be a waste of time and resources, so I will advise you start writing proposals to different companies that may need your services; look for a brother, a church member and other people that could be of help in making sure your proposals pass through the right offices.
Then begin to strongly think of given yourself a proper packaging. I mean people loves to look at things at face value in this part of the world, so you can also meet their expectations by looking very good, and in the right frame of mind when you would be going for a presentation. Wear a suit or a corporate dress well ironed, if possible rent a car with a driver for that day. A man was able to secure a contract of hundreds of millions of naira because he was wearing a Rolex wristwatch he borrowed for a business meeting; same as for car, e.t.c.

Before the big jobs start coming, be a subcontractor to some major contractors, our dailies are filled with the advertisement for subcontractors from big time contractors. Check Tuesday Guardian newspaper and others. The money you make will help you to stand as a contractor ultimately later on, and you can be quoting for jobs directly.
Be articulate and bold, you need this if you are going to win any contract.
Find out where to source for equipments before bidding for any project; all projects have their own peculiarities. Do not bid for a project because you are desperate to get a job, else you might bite your fingers at the long run.
Pretend and present yourself exactly the way the client would like to see you and feel about you. The client won’t be happy to know you are a hungry man that needs their money to get out of poverty. He will also not be happy that he is given out a job of a big magnitude to somebody that has not handled a job of that size before. Avoid what will make the client to doubt your competencies.
Use professionals as business partners, and leverage on their expertise; just agree with them on a percentage sharing formula and you are on.
Source for loans from families and friends, especially when there are no interests, or that it is very low; but make sure you are working for an organisation that will pay you in time and that they have a record of prompt payments to their contractors.
Lastly, pray for the success of your projects.

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TYPES OF FOUNDATIONS AND THEIR USES

Foundation of building, as the name implies, is the starting of a building construction on site. Types of building, nature of soil, and environmental conditions are the major determinant of the type of foundation you will use for your building.

1) Strip foundation- This is the most common type, it is mainly used where you have strong soil base and non-waterlogged areas. Most small buildings of just a floor are constructed with this type of foundation.
Depending on the structural engineer’s recommendation, the depth of your foundation could be from 600mm to 1200mm (mostly for small scale buildings). When the soil is excavated, a level at which the concrete will settle evenly is established, then concrete is poured. This may be from 150mm (6”) thick to 450mm (18”) thick, depending also on the type of building. After that, blocks are set round the trenches at the center of foundation; the foundation usually follows the block lines. The blocks are then laid to d.p.c level before another concrete is poured on top, this is the german-floor or oversite concrete. This type seems to be the cheapest.

2) Pad foundation- This is where isolated columns (pillars) are casted from the foundation to carry a slab at the top of the ground. This is mostly used when you want to make use of the under of building as parking space, or when the other space is not conducive to have foundation. Imagine you are planning to build a house across a flowing stream and you want a situation where you can use your boat to pass under the building because the stream is underneath. Then you may not need to dig foundation that would cut across the river; but just by applying columns (pillars) at the edge of the river like a bridge. These columns are thus isolated, and their foundations are referred to as pad.

3) Raft foundation- This is where you have concrete spread around your building from the base of foundation all through to the german-floor/oversite concrete/ground floor slab. It is mainly used in areas where the soils are sandy and loose. Most of the time, you spend more on this than the other previous two. It is also recommended in waterlogged areas, but with buildings of fewer storeys.
It has ground beams which shoots out from the foundation base, and is also attached to the ground floor slab to form a network of concrete embedded round the building space. The ground beams are usually from 600mm to 1200mm for low buildings.

4) Pile foundation- This is the most expensive and the strongest type of foundation. This requires specialist engineering to construct. The soil is bored deep down the earth, and filled with concrete to be able to support loads of multi-storey building on top. Most skyscrapers are constructed with this type of foundation. A high building in a waterlogged area may also require this type of foundation.

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HOW TO BUILD YOUR OWN HOUSE FROM A N10,000 SALARY

Anybody, no matter the stipends he receives as the take home pay, can actually build his own house. It takes just determination, knowledge and persistence. A lot of people today have increasingly come to find out that you don’t need your entire life savings just to get a home. Rather what you need is adequate planning and ability to know the difference between wishful thinking, reality and actually taking action. There are always a category of houses for every class of persons in the society.
First of all, you need to calculate the amount of your salary for 2 years and find 30% of the sum. Whatever you get, just meet your building professional and ask him what kind of building the 30% can cover for its foundation only. If you get that, then know it that you can easily build your house with that terribly miserably low salary you take home every month.
Assuming your salary is N10,000; for 2 years your total salary will be N240,000; and 30% of this will give N72,000. This can conveniently cover a 2 bedroom flat strip foundation.
But you think you can’t possibly save 30% of your income, because your salary is already too low. Let me tell you, from studies carried out, it had been known that no matter how extremely small a person received or how poor he is, 30% or even more of his money goes into what he can’t account for monthly. He just needed to sit down and take stock for a month, and he will see that he had been spending 30% and above on very unimportant things in his life.
Yes, I know cost of land is high, but that is because you don’t want to live the crowded and so called urban area for the outskirt.
You can also save for land if you put your mind on it. But if you already have one, then your dream of getting your own house will be faster than expected.
Within 10 years of determination, you will complete your project.

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