Saturday, 29 July 2017

Using Bamboo in place of 'Iron Rods' in Concrete - Engr. Osaz’ ENOBAKHARE

There are now sufficient reasons to appreciate suitable alternatives in today’s construction. Whether it’s due to cost considerations or environmental factors, exploring alternatives is highly welcomed. Being the world’s most commonly used building material, nearly all our buildings have a signature of concrete on them. Unfortunately, the cost of a cubic-metre of concrete produced in Nigeria has nearly doubled in recent times. The price of iron rods (or steel rebars) is also largely unstable; swinging here and there like a triggered pendulum. 

There seem to be absence of any serious price regulation mechanism and the manufacturers also have their own side to the story – exchange rate issues, increased cost of raw materials, taxation and all sorts. It is not clear whether the building industry has any special provision for the average person or the common man. Interests charged on financial loans are not encouraging. You can go on and on; but complaining is obviously not the solution. They say if life gives you lemons, make lemonades out of it. Here we are; we need to reinforce concrete to maximize its potential and we have got an option –bamboo.

Tested, tried and trusted, bamboo has appreciable tensile and compressive strengths making it suitable for use as reinforcement in concrete. With ultimate tensile strength reaching 124N/sqMM, it only takes a combination of bamboo strands to equal the 250N/sqMM ultimate tensile strength of mild steel and 460N/sqMM  tensile strength of high-yield steel rebars in common use today. More so, provision for bamboo reinforcement in concrete is structurally designed in the same way as steel rebars; the mix ratios and construction processes for bamboo in concrete are not different from the norm, making it not necessarily a change in technology but a change in the material used. It’s that simple!  

There are around 15,000 species of bamboos around the world; the suitable variants are abundant and wasting away in our mangrove forests and elsewhere while we simply look away. There is need to put on a thinking cap and intensify research on the use of the naturally-occurring bamboo which is bio-degradable and eco-friendly than the carbonized steel rods. However just like every other construction material, bamboo has its own limitations; perhaps that is why it has not been approved for use in fully load-bearing members. Does this mean it can’t be used for concrete at all? No!




Bamboos, like several other plants when placed in water tend to absorb it and swell. As it expands in the concrete, it makes the concrete to crack. Water is needed to work concrete and there lies an issue. Researchers have provided solution to curing bamboo to be used in concrete so that it does not absorb water as much as it would normally do.  This treatment can be done right on the site or through other industrial processes before taking the bamboo strands to site. You have to be sure to select healthy brown ones with sizable culms to reduce the cost of treatment. Another worrisome issue was the bonding potential. Naturally bamboo has a smooth surface so it may not bond properly with cement, sand and granite or other aggregates in the mix therefore the strands are often chopped in various sections along its length before they are used in concrete. 


Beyond these two prevailing limitations, what bothers users is the durability of the material in concrete; that’s why it’s not yet broadly applicable for use in fully load-bearing members. As it stands now, the improved variety can be comfortably used for concrete piers, coping and panel of fence walls, lintel beams, ground floor slabs (or ‘German’ floors) in areas with low water table, construction of concrete kerbs, dividers, entrance pavements, wholly in concrete in temporary structures, roof parapets, ground decks, in the construction of low traffic concrete roads and as composite placed side by side with iron rods. Using bamboo as reinforcement slashes the cumulative cost of producing reinforced concrete by almost half. There are no known producers of the improved variety of this material in the country and this also poses an investment opportunity to investors interested in alternative building materials and technology. 

Wednesday, 12 July 2017

Bad Rendering or Plastering of Your Walls: Here is what to do - Engr. Osaz' Enobakhare

‘Perfection’ is the word. ‘Smoothness’ is the feeling. ‘Mortar’ is the item. The wall is the receiver and we are the admirers. Everybody wants a perfectly smooth wall for their interiors but we sometimes get more than what we bargained for. Rough, uneven and not properly detailed wall plastering or rendering are some end results that stares us in the face because we somehow engaged the wrong hands. But that’s not the end of the road. 

Rendering (or plastering) action on wall usually precede painting. It is the process of applying mortar made from a mix of cement, fine aggregates (or smooth sand) or Plaster of Paris and water to cover the surfaces of block, brick or concrete walls. This process if not properly handled can lead to a bad output. 
For instance there is often the problem of unevenness in the texture of the finish, flaking-off, breaking edges, cracking, etc. which hitherto affect overall aesthetics and durability. But not all cracks on walls are as a result of poor mortar or rendering work; sometimes it is a consequence of structural defects in the building. Sometimes when this happens, there is a temptation to simply cover it with paints or other finishing material; but that really doesn’t work. The effect of a bad plastering will still resurface with time. Talking about getting the job done properly; it is important that the mason team understands the mix ratio for mortar in order to get the right output. They must also know how to use the trowel (or application device) and smoothing devices well. A cement-sand mix ratio of 1:6 -12mm thick is generally acceptable for walls; corresponding to about 3 wheelbarrows of smooth sand to 1 bag of cement. 12mm specified here represents the thickness of the layer on the wall after application.

The nature of sand is also important. The suitable grade of smooth sand for wall rendering is one that contains a good proportion of clay which gives it a tacky or gummy feel. This does not imply the use of pure laterite. The use of sharp sand for rendering should be avoided because overtime pores are generated within the layer that affects the surface texture of the wall. The moisture content in your mortar should be adequate; just enough to make the mix workable. There are special cements used to achieve quality rendering; they were produced with the required functional requirements of good mortar/plaster in mind. It is good to make use of them rather than the general purpose cement so as to obtain great results. It is wrong to use mortar made for setting blocks or bricks to also render your walls because the composition are naturally different. Naturally if you make a bad mortar, you can only expect a bad rendering.

 Building Contractor in Nigeria

Once there is a noticeable defect on a rendered wall, even if it has been painted; it is better to simply chip-off, prepare the surface and reapply properly so that it cures without cracks. Although it may cost more to chip-off old rendered layers before re-applying mortar or P.O.P, the durability potential often override the cost burden, hence making it a cost-effective approach to the alternatives. The use of filling materials to close-up voids in walls to create even texture without chipping off in walls is a welcome development but it is not often the best option; especially if the defect is on a large scale. If you must use filling materials some Experts advice that you drill tiny holes into sections of the wall (using a simple drilling device) to allow for a good grip to the wall; the hole is such as extends beyond the plastering layer well into the wall fabric. Special gums are sometimes used to fill the hole to enhance firmer grip; thereby improving stability in the face of shocks.

Saturday, 8 July 2017

Flooding: Turning Your Perimeter Fence into a Retaining Wall - Engr. Osaz' Enobakhare


Security and privacy are common reasons for constructing perimeter fences around a building. Some fences are simply symbolic while others are basically for defense. They also help to prevent land encroachment from neighbors which is not uncommon in this clime. However, fences can be designed to perform yet another critical function of flood control especially for buildings constructed in areas prone to flash floods, run-off waters from faulty drains, erosion, etc. This is the core functions of embankments and retaining walls including the ability to stay earth. Retaining walls hold back or fend off flood waters from entering into your compound. There are a number of designs and technologies suited for this purpose and they can be incorporated into your fence wall and not necessarily constructed separately; saving cost and space in the end.

Generally, aesthetics is valued from outside in, not necessarily inside out. Therefore the perimeter fence and gate of our houses becomes a very vital point for aesthetic reference for the buildings as a whole, being mostly the first point of contact. 


This places a burden on the designer (or architect) to allow for aesthetic considerations for perimeter fences intended to serve as retaining walls or embankments; understanding that these fence types will be under intense water pressure when the weather goes wild compared to ordinary fences. Only suitable color, texture and styles should be used for the finishes of such fence walls. Stone-based finishes are often recommended while some others prefer to use special moisture-resistant paints and coverings. There is also the structural engineering consideration which factors in the strength, stability and durability components. If the fence is beautiful but cannot stand strong against flood pressure adequately, then it may be considered good for nothing. The method of building them is slightly different from the normal ones. One striking difference is that the base for retaining walls are normally higher than those of other fence types usually extending beyond the level of projected flood heights before block walls are introduced. Some are even designed to be trapezoidal rather than rectangular in section.

Perimeter fences are normally designed either as non-load-bearing or partially-load-bearing walls but those intended for retaining walls are essentially load-bearing walls. They do not support their weights alone or small loads from security furniture but also sizable pressure forces from external flood. There are various types of materials that can be used for building special fences of this nature; the most common type is concrete. Other types include a composite of reinforced stabilized earth with bricks or blocks as well as other poly-based substitutes for concrete. Whichever material is used, there is need for it to possess sufficient strength to withstand the pressure forces of water as well as be stable enough not to deflect, crack, fail or over-settle in the process. It should also be able to perform this function throughout the life span of the building or space it was designed to serve.

In areas susceptible to flood, the sub-surface soil conditions are often poor because of the long overbearing effect of stayed water on them, so there is always a need to take cognizance of the nature of the soil during the design of the fence. Well-built solid raft base or a combination of short-bored piles and reinforced concrete strip are good options for the foundation of such walls. Reinforced stabilized earth has also been successfully used for this purpose and is said to be a cheaper option to both polymer-based fences and concrete. 


Flood control is serious business especially in rainy seasons. There is no better way to imagine the devastating effect of flood than to watch a house go partially or completely under water; destroying the building fabric and other valuable properties in the process. Although fencing alone cannot completely take care of flood on a large scale however it is known fact that the retaining wall fence type surely minimizes the effect by helping to redirect water from a property.   

Saturday, 15 April 2017

The Red Road: How to construct Estate Roads with Lateritic pavers - Engr. Osaz’ ENOBAKHARE

In-tune Developers and Estate Owners with an eye for budget-friendly yet aesthetically-appealing, stable, strong and durable estate infrastructure are already exploring the option of adopting the ‘red road’ technology. With the abundance of cheap and good quality laterite deposits in various parts of the country on the one hand and the prevalent rising cost of construction materials on the other, the use of lateritic pavers for estate road construction in place of concrete interlocks and asphaltic (tarred) roads may just be the real deal.


In structural/highway engineering terms, the Red Road is designed as a light and medium-traffic road with individual unit of paver having the same compressive strength as that of Grade M40 concrete (i.e. 40N/sqMM) as obtainable in concrete pavers for the construction of similar road types. Light and medium traffic roads includes car parks, office driveways, housing estate roads, rural roads, farm houses, office/commercial complexes, boulevards, city streets, small market roads, intersections/rotaries, utility cuts on arteries, service stations, etc. If properly constructed, the red road sufficiently satisfies nearly all known functional requirements for roads with durability potential believed to span beyond 50 years during which only little maintenance is needed. 



Because one of the main constituent material, Laterite which usually amounts for more than 50% by volume of the mix in the red pavers normally contains up to 70% clay -which is known to be ‘plastic’ in nature, the thin gaps or voids between interlocking pavers allows for expansion and contraction across various seasons and at different temperatures; although a suitable infill material which does not affect this natural process can also be used to seal the void. Some engineers also lay damp proof membrane (dpm) beneath the bed in areas with high water table. 



As applicable with concrete pavers, pavers for red roads are built on good bedding usually made of highly-draining sand spread uniformly to form a longitudinal bearing throughout the surface area of the road up to a thickness of 100mm or more depending on the subsoil conditions. Stoppers are installed at the edges of the road with protected linkages to the adjourning drainage to prevent the bedding sand from washing off. In areas where highly compressive soils like clay and peat are encountered at near surface levels, the poor soil is first excavated and a more stable earth fill is used to replace it before the bedding is made. The bedding in any case must be properly leveled and compacted before the lateritic pavers are laid to avoid depressions, bulges and over-settlements at various sections as they receive varying degree of stresses from live loads.  
  
Red roads are built from lateritic pavers made of a stable mix of laterite, crushed stone/stone dust and cement. The proportion of each constituent material known as the mix ratio largely depends on the expected bearing capacity of the road. For instance, the percentage by weight of stone dust in the mix is often higher for pavers to be used in main arterial roads (i.e. the road(s) leading from the main estate entrance gate to the streets) than the pavers used on the streets (or branch roads) because the load bearing requirements are relatively different.


Recently (March 2017), a kilometer of dual carriage red-road to be constructed by an indigenous firm in Garki, Abuja has already been estimated to cost some 37% less compared to the use of conventional methods. Interestingly also, for lovers of road ‘black’, the red road can also be sprayed black with hot black soot material at an extra fractional cost and still maintain its functionality. As it stands now, Red-roads may soon become a part of our road life.

Why You Need A Material Schedule For Your Project -Engr. Osaz' Enobakhare

Sometimes the use of direct labour in conjunction with supervisory and quality control inputs from one or two professionals is seen as a more budget-friendly approach to the delivery of a project, especially small-scale projects. Other times, the project owner may choose to be engaged directly in purchasing and organizing the supply of construction materials to their site, also in a bid to save cost. Whatever the case may be, whether it’s your personal project or as a group, it is important to know what and what you should expect at completion. You don’t plant grapes and expect to reap blueberries. A project for example, a building development is essentially a product of the use of materials and workmanship. You don’t order for tiles and expect to see epoxy flooring; neither would you see a classic brick wall when you actually paid for blocks.


The usefulness of a material schedule is undoubted. You may never know it until you lose money buying the wrong or a substandard material at the same price as the original or even more. It is that piece of document that shows you the types, sizes, quantities, quality specifications and sometimes current price of all the materials you would need for a project from start to finish. It is not the same as a Bill of Quantities (B.O.Q) or Priced Bill of Quantities which gives brief details of all the items of work in a construction project and cost included respectively, it doesn’t give you the work item or work processes, it only deals with the materials aspect.

The Material Schedule is presented in such a way that the user can easily identify with what materials will be used in the construction of his/her project and it often reveals approximate quantity estimates of all the materials needed with minimal allowance for wastage. Usually the material schedule is a construction document prepared after all the relevant designs/drawings has been completed so that at no point is any material is omitted due to incomplete architectural and engineering details and a thorough market survey has been done to check availability and current prices of the required materials. It is often done in conjunction with the owner’s specifications.

When engaging a contractor, it is important to ask for a material schedule so that you can follow up on the quality of materials used for your work. If the materials used are not those you have agreed on as duly reflected on the material schedule in the absence of a pro-work variation, you can call for a replacement. But if there are no documents to show material specifications, then you can expect anything. Sometimes regret may follow; this is particularly the case when a nominated supplier is engaged without a material schedule to back up your claims on the specs of the materials ordered for. Take for instance, you need a simple timber (wood) to construct your roof carcass, if you don’t specify the product type, size and condition (e.g. Mahogany Hardwood, 50 x 75mm full lengths, new and smooth) but just say supply me ‘wood for roofing’ who is to blame when a truckload of used fragile softwood is brought to your site and workers begin installing them?  Although the material schedule comes at a cost, it is worth it.

Saturday, 11 March 2017

Why It Is Structurally Wrong To Build Directly On Sand - Engr. Osaz’ ENOBAKHARE

As construction cost rises due to attendant rise in prices of building materials, the trend of building houses directly on sand has been observed to be on the increase especially by unscrupulous developers and contractors. Having carried out an independent monitoring of construction activities in some areas in the Ajah axis of Lagos lately, it became obvious that in order to save cost people have resorted to constructing buildings directly on sand.

The awkward idea been adopted in most of the cases under study is to sand-fill the land, level and compact it with the use of machines and the construct a reinforced concrete strip foundation directly over it without recourse to minimum construction/engineering standards.

They do so very quickly so that before any of the regulatory bodies saddled with the responsibility of building control gets wind of their ill act, they are already on super-structure level at which point it is burdensome to ascertain how the foundation was actually built. 

On a particular site, using this vague method the entire foundation including the ground floor slab was put up in one week and by the next week, they were already building up the walls and frame. Dishonest developers thrive in such indecent acts and sell or lease these buildings to unsuspecting prospective buyers who in-turn occupy them or cause others to do so by way of lease/rent too. There is no consideration for lives and properties put at risk of an imminent collapse even as some of the buildings observed are already exhibiting symptoms of instability and sick building syndrome pre-occupancy.

Five years post-occupancy, the building over-settles (or sink) and then tilt in a particular direction. When asked, some of these developers claim that before there will be any major issue with the building they would have recouped the returns on their investment and its left to the new owner to do a repair by way of underpinning as the need arises. To know that some greedy professionals have joined the bandwagon of quacks in delivering such poor structures is condemnable. This act should not be encouraged in any form.

Here are some structural considerations; normally after leveling and compacting operation has been carried out on a sand-filled land it still remains a made-up ground. Although the land becomes stiff at sub-surface levels, this doesn’t in anyway erase the fact that the underlying bad soil (or peat) remains intact and retains its poor attributes. Peats are highly compressible soils and will naturally compress upon the impact of load. As this happen, the building will settle indifferentially, especially during seasonal changes and mass movement of the earth; which occurs at various times of the year.  Such structural anomaly often leads to poor stability of the building and eventually a collapse if unable to bear the load, especially for single or multi-storied structures.




Rising cost of building materials should not be a yardstick to adopt poor construction methods in the construction of buildings and estate infrastructure anywhere. The authorities should not turn a blind eye to such activities that jeopardizes or threatens the lives of people as well as the overall health of the built environment. Project owners and developers should not connive with contractors or builders to manipulate well established engineering prinicples. It is important to select a good contractor for your projects. Yes, there is room for adopting cost-saving methodologies like the use of dry construction methods, cold brick construction, etc but bad construction methods is never the way to go.   

Thursday, 9 February 2017

Dredging to Sand-fill an Estate: The Tricks and Gains - Engr. Osaz’ ENOBAKHARE

Developing housing or industrial estates close to large water bodies throw open the option of dredging to sand-fill with the aim of reclamation or just to prepare the site for the construction of buildings and infrastructure on it and/or to get sand for the actual construction. In more extensive application, sands can be dredged to stockpile and sell. Basically, for estate development the option of dredging is often weighed alongside the possibility and cost-effectiveness of the alternative approach of trucking sand from nearby sources.

Contrary to popular opinions, industry estimates reveal that for mini-estates (of 5 acres or less) located close to water bodies with shallow fill depth (not exceeding 1-metre) and where manual dredging is prohibited, the option of trucking has proven to be cheaper than mechanical/hydraulic dredging. 


Besides unlike dredging which restricts the user to the particular quality of sand deposits available in that water body at the material time, trucking also allows for the use of a variety of filling materials. However beyond these rare scenarios, mechanical/hydraulic dredging remains the best approach.

Although manual dredging is still the cheapest form of dredging, it is tedious, relatively slow and highly risky hence no longer in vogue. Mechanical/Hydraulic dredging allows for the digging up of mud, sand, gravel, pebbles, rocks and other deposit from the bottom or sidelines of the water bodies by means of a mechanically or hydraulic-driven equipment known as a dredge (or dredger). There are various types of dredgers each defined by its mode of operation. However local industry folks can easily relate with two popular types which are Cutter-Section and Plain/Jet Suction Dredgers.  The striking difference is that the former cuts into the bed, agitates it and sucks up the mixture before transferring it to the end point through a pipeline while the Suction dredger simply sucks up the sand directly and transfer.

Dredging activities requires you to obtain a license/approval which is given by the appropriate authorities after providing relevant documents. These conditions defer from state to state across Nigeria but generally a sand search is often conducted at first to determine the source, availability/quantity and quality of sand in the water body or shoreline to be dredged. This sand search result is often the first and major item developers look out for in a hydrological survey carried out pre-dredging. There is really no need attempting to dredge what is not available in required quantities? A Bathymetric survey is also carried out to determine the depth and bed ‘topography’. Both surveys are often used interchangeably to mean the same thing but they actually have their specifics. An Environmental Impact Assessment (EIA) is then carried out to determine the level of impact the proposed dredging activity will cause to the environment. 

The most suitable type of dredger to be used for a project is largely determined by the cost of purchase or leasing, the size of task to be performed, pumping requirements par efficiency as well as the nature of the sand deposits present. From observation, most small estate owners normally opt for suction dredgers of 8 – 14 inches with sand capacity averaging 350 cubic-metres of sand per hour; relatively cheaper to purchase or lease.  Larger cutter-section dredgers sizing up to 18 inches or more with sand capacity reaching 1000 cubic-metres of sand per hour is in high demand among medium and large estates’ owners. Experience shows that the rate of breakdown of jet suction dredgers on sites is relatively higher than the cutter-section type owing to their inability to withstand stresses associated with sucking up very stiff clay and rocks. But in any case, with a good dredger pumping sand constantly into your site, the heavy cost and risks associated with long-distance sand trucking is completely erased. 

Wednesday, 8 February 2017

Improving Construction Speed by Mass Block Production - Engr. Osaz’ ENOBAKHARE

In most completed building projects, the items of work either classified as wall or associated with the use of block/bricks normally constitutes at least 20 percent of the total volume of work done. Now that’s substantial. Block/Brick wall often extends from the substructure through to the superstructure and extensively, the external works. In Nigeria, the most common types of walls built till date are made from hollow sandcrete blocks which come in standard widths of 6 and 9-inches (i.e. 150 and 225mm). Although in some parts of the country, there is appreciable use for solid sandcrete blocks.

There is also a growing market for baked Redbricks, Polyblocks, Lateritic Coldbricks, Nvarsform, Hydraform, Ecobrava, etc. as well as hollow and solid concrete blocks made from crushed stones. But put together, they still accounts for less than 50% of the total existing wall forms in modern construction in the local industry. For medium and large sites, it has been observed that the time taken to produce blocks/bricks readily available for use is often mismanaged thereby contributing largely to project overstay. 


On the one hand, contractors have overtime observed that relying on supply of blocks/bricks from a production factory increases the overall project costs and do not always guarantee desired quality and speed of delivery; therefore it becomes imperative or perhaps reasonable to produce on site.

Visits to several estate project sites across the country recently reveal that the old single-or double-mould block machine is still in common use. When asked why they choose to stick to the old ways of doing things, they often lament that they do not have reliable information on how to get mass block/brick production machines and may equally not know how to use them. Working with a unit of the popular single-mold machine, workers are only able to produce some 300-500 blocks per day (i.e. 8-hour construction time). Then the down-times which are pretty-more frequent than the new variants. These low production capacities measured against time spur contractors of sizeable sites to acquire some more units of the same ‘old-clog’ machine just to beat time. But why have 3 units of the same machines with 3 different operators each and their respective 4-man supports to produce say 1000 blocks a day when with just a single gang you can produce 1000 or more blocks a day using a single unit of mass-production machine? Ironically, its penny foolish, pound foolish.

Furthermore, using variants of multi-mould machine erases the cost associated with the use of block palettes (i.e. the sitting table/plank for freshly-molded blocks) which as at December 2016 goes for an average price of 400 Naira per piece. The new machine class literarily lay blocks directly on the floor as it pulls along. In-tune contractors and block makers are fast trading-off their old machines for the new variants. Interestingly, most of these machines possess higher compression potentials and come with automatic mould changing functions. Some users order for those with trio-capacities; for produces blocks, lateritic bricks and concrete pavers together.  For mega projects, machines with installed capacities of 3000 - 5,000 bricks/blocks per day are highly recommended. It is believed that the market for these new machine variants would increase rapidly in coming months. 

Monday, 23 January 2017

Limited Space to Park Cars? Car Park-Lifts Can Help - Engr. Osaz’ ENOBAKHARE

Advancement in technology has enabled parking of two or more cars on top of each other within the same floor area without having to construct any new concrete slab. This is relatively convenient for offices, malls, hotel or living apartments with limited car parking spaces. Car Park-Lifts as they are fondly called back here consist of an often open-ended mechanical lift that can lower a car to park below earth while platform(s) within the system automatically slide and lifts the other car(s) to be parked over it and by means of a remote control, extends out again in a systematic manner to allow access to the drivers to move their cars away at any time.  This way, the vehicles are safely kept in position and the attention of other drivers does not necessarily have to be drawn to the park if a user of the system intends to drive out. This slide and lift mechanism help maximize space and enhances security of motor vehicles parked especially in public places where often ‘cars are parked at owner’s risk’.

As it stands now, there is only a little presence of semblance of car park lifts in the country but it is believed that as cost of lands in metropolitan cities continue to rise, developers and building owners who intend to maximize the benefits of their land would embrace this technology. Besides because of the thrill and ambience that lifting cars before driving-out brings, it is often used as ‘stunts’ by wealthy individuals who are often keen on impressing visitors -showcasing class and style even when space is not an issue.

Car Park-Lifts are so designed to take care of the weight of a wide range of cars intended to be accommodated by them without falling-off or failing at any point throughout their life span and like the cars they were built to keep, they also need periodic maintenance. Also, like many other lift systems, they run on power. More recent models now come in self-powered, low energy configurations. Special Park-Lifts are designed and built for heavy vehicles like tankers, dump trucks, etc. There are very rare cases of vehicles getting trapped in the system and most of such reported cases across the world have been caused by power outages or poor maintenance of the system. 
   

Car Park-Lifts are factory-built and may or may not be installed over an excavated portion of land. For those with underground features, the usual construction process of setting out, excavation and surface preparation is done and with the aid of a hoist and other related equipment, the already assembled lift system is placed right inside the excavated area on the basement floor. The system is thereafter connected to electric source to power on. Afterwhich it is test-run for safe use.


For commercial buildings with high vehicular traffic, several units of this park lifts are often installed side by side while an electronic card is issued to users which helps them control the slide and lift functions of the unit housing their individual vehicles for the time of using the park. These cards are then retrieved from them at the exit point and given to other users in that manner. The system is easy to use, quicker and relatively cheaper than constructing traditional multi-level car parks and can be installed almost anywhere. 

Monday, 2 January 2017

High-Rise may soon use wipers - Engr. Osaz' Enobakhare

A young Nigerian Engineer, 27 is working on developing automated detachable and retractable self-powered wipers to clean surfaces of glass facades, glazed wall panels, tiles and cladding on high-rise buildings of dust, molds and stains. A clean glass improves visibility and enhances the aesthetics of the building on which it is installed. 

The proposed wipers are similar to those used in motor vehicles except that they are exceptionally longer in length and so can cover a larger area. Buildings 18-metre or more in height above the natural ground level are often classified as high-rise buildings. The cost, risks and complexities involved in maintaining the exteriors of high-rise buildings may reduce drastically if this invention sees the light of the day. Considering the growing number of high-rise buildings across the country and by extension all over the world, there is likely widespread in the adoption of this technology. 


The first prototype of the wiper would be available in 2017. The idea of powering itself is so that as soon as it is programmed, it continues to perform its duties irrespective of power outages. There are indications that the wiper will rely on solar power. This is based on the fact that solar panels can fit in perfectly into the engine compartment of the wiper. The wiper itself is not to be programmed to work every day, hence there is ample time to collect and save energy for next use. The wiper engine compartment is to consist of water channels, micro-tanks and sprayer that automatically spray clean water and liquid soap on the surface as the wiper’s blade wipes across.


Photo Illustration of wiper on a high-rise building
Ideally cleaning of glasses is to be carried out every year, especially during the dry season when dust naturally gathers on glass surfaces but with this invention in the pipeline, cleaning can be done by just anyone every other day. Due to the cost implication of such exercise it has been observed that most high-rise building owners in the country normally carry out maintenance every 5-10 years. The cost implication is even higher for sky-scrappers.

The price and durability potential of the building wiper is not yet known but it is not baseless to assume that this concept is a cost-effective maintenance solution. According to the inventor of the building wipers, they are to be attached to a top beam or roof of the building from which they stretch out their blades to wipe and then automatically retract back to original position after cleaning operation is completed. Its component parts are detachable and the wiping blades can be replaced with even greater ease. Enthusiasts are imploring that smaller model that can be used for small residential or low-rise commercial buildings should also be produced.