House, does anyone have an idea or contacts where one can buy quality vibrated building blocks in Owerri or Umuahia.
Also btw Vibrated and hand moulded which is better. Can someone throw more light on building blocks.

Good evening Flav,
There are a number of vibrated block companies in Owerri. One is Badger Brickyard Limited (BBL) located along Aba-Owerri Road, before Obibi Junction, Naze. You can reach them at 09081949695 or visit their site at http://www.badgerbrickyard.com/get-a-quote to get a free quotation.

A number of factors determines the quality of blocks. These include: cement/water ratio, cement/aggregate ratio, cementious property of aggregates [ie stonedust (stonecrete) blocks are stronger than sharp sand(sandcrete) blocks, all things being equal] evenness of mix, whether or not the blocks were completely moulded within the setting time of the cement, among others.

Assuming that the cement/water ratio and cement/aggregate ratio is the same for both the vibrated and hand-moulded blocks, Vibrated Blocks will still be better, stronger and last longer than hand-moulded blocks for a number of reasons:

The main difference is that the aggregates (sand, dusts, cement, water, etc) in the mix are compacted using vibrators which compacts the blocks with a force that is way higher than hand compaction. This ensures that all the spaces in-between the aggregates in the mix are filled up completely. This increases the density of the block and therefore the compressive strength of the block. Note: Compressive Strength determines the load that the blocks can carry. In Nigeria, the minimum compressive strength for non-load bearing block is 2.5N/mm2 while for load-bearing block is 3.5N/mm2. Hand-moulded Blocks may never achieve this compressive strength. That is why in cities like Lagos and Abuja, Engineers and Builders are discouraged from using them, as a matter of policy.

Another difference is that hand-moulded blocks are usually made from manually (with hand and shovels) mixed aggregates which is usually not evenly and completely mixed due to human errors, while SOME vibrated block companies (like Badger Brickyard Limited) use electric Mixers, which ensures even and thorough mix as well as well prevents escape of moisture/water from the mix during mixing and moulding.

All things being equal, comparing vibrated blocks to hand-moulded blocks is like comparing Mercedes G Wagon with Keke NAPEP. Well, I hope the general point has been made. I hope this helped.