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Articles about Building Material:


  1. CEMENT POLLUTION
  2. TIMBER INFORMATION - Timber Engineering Europe

CEMENT POLLUTION


Wash Out and Wash Water in Construction
Concrete is a product that has no place in modern construction, not least for its damaging effect on the planet at the birth of the odious stuff, but for the after effects it leaves behind. In the past, I have discussed the massive embodied energy emissions this outdated and unwelcome material creates as well as many other reasons for not using it in construction. There are two very undesirable and hugely unwanted effects of concrete production and use, that the vast majority of us do not know about, simply because they are never brought to our attention! The first effect I refer to is:


Washout

Washout is exactly what it says it is – Washing out concrete carrying or delivering apparatus, such as mixers, pumps, trucks and hoppers. In each case after every operation, the equipment must be thoroughly cleaned – its obvious why, because if the machinery was not cleaned with copious quantities of water, the concrete would set and very expensive plant would have to be sent to the scrap yards. It has been a known “punishment” in the industry for a disaffected concrete worker to leave a couple of cubic metres in a drum or in a chute over the weekend, resulting in a massive solid problem for the boss on Monday!
So where does the washout and wash water go? This is an operation that is rarely mentioned, because although rules may exist, nobody supervises the washout operations. If the residue of the washout operation permeates the earth or worse a drain, it leaves deposits of Chromium V1, Copper, Iron, Selenium, Vanadium and Zinc
The lime found in cement and concrete products easily dissolves in water, just like sugar. Lime is alkaline, so as a result concrete slurry and any water that comes into contact with cement or concrete, becomes strongly alkaline (pH11-13). This is deadly to aquatic life.
Plants, insects and animals can be burnt or killed by high pH water. High pH substances such as slurry or concrete wash water will attack the sensitive membranes of fish and eels, including the gills and the skin; effectively burning them much the same way acid burns us.
Often fish and eels try to jump out of the stream to escape the burning water resulting in death by suffocation. All life in a stream can be wiped out by a concrete or cement slurry or washout discharge, and will take years to rectify. A recent report from New Zealand indicated that 30% of fish that died as a result of poison discharge were killed by washout discharge.

In the USA alone the amount of concrete washout material and wash water generated each year accumulates to approximately:

  • 34 times more concrete than was used to build the Sears Tower in Chicago (2 million cubic fee/72,000 cubic yards), the World's tallest building until 1996
    or
  • Enough concrete to build an 8-lane freeway system 175 miles long
    or;
  • Nearly 3/4 the amount of concrete used to construct the entire Hoover Dam and
    Enough water to provide a city of 50,000 people for nearly three months.



Imagine how much wasted water is used not just making concrete, but with the wash water needed several times a day.


The second little known, but large problem is Cement Carbon Emissions
We all hear about the effect of concrete in construction and the main carbon emission offender is only one component of concrete – Cement.
While most of the population has been busy worrying about travelling by air and car in a responsible manner, the cement industry has been quietly pumping more CO2 emissions into the air, more than the entire aviation industry. Cement manufacture is responsible for 5% of all global industrial carbon emissions and is increasing rapidly. China alone was responsible for 540,000 tonnes of carbon dioxide emission last year, as a result of cement manufacture.


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TIMBER INFORMATION - Timber Engineering Europe


All timber used by our company MUST be of a recognised type and origin. It also must pass certain test rules and treatments:


  1. The only timber used by us is the type classified as Spruce/Pine/Fir. All supplies are from Northern Europe, Russia or Canada and all MUST come from replenish able sources, under a chain of custody suppliers agreement. A "PEFC - TRADA" certificate must be in force at the time of supply.
  2. As subscribers to the system we contribute to growing 252 million cubic metres of wood SURPLUS to requirements (after harvest) EACH YEAR. This means that we add a forest in Northern Europe the area of Cyprus EVERY YEAR, besides replacing all the harvested timber.
  3. The wood is sent to mills to be converted to Canadian Lumber Standards (CLS) this is planed all round and thicknessed to ensure close tolerances can be achieved.
  4. All the planks are then stress tested to ensure that they will meet the stringent conditions laid down by various European codes.
  5. The planks are then Vac-Vac Treated as follows:
    • Planks are placed into a treatment vessel
    • A vacuum pulls the air out of the wood and the vessel
    • Osmose preserve is then flooded into the vessel
    • The vessel is then pressurised, forcing the preservation fluid into the timber.
    • The fluids are then removed, and a final vacuum is applied sucking out all excess fluid
    • The timber has now been treated against Wood boring Insect and Fungal Decay
  6. The fluid used is a water-borne borate base which is harmless to any wildlife and is environmentally accepted globally.
  7. The last operation is KILN DRYING. All timbers must be kiln dried to max 19% moisture content, to avoid any problems post-construction.

ALL TIMBER MUST MEET:

  • U.K. Building Regulations
  • TRADA
  • British Standard Institute (BS5268)
  • Robust Detail
  • SAP Energy Rating
  • NHBC
  • Etag 007
  • Euro Code 5
  • European Technical Approvals (ETAs)
  • CPD: EN 13986

We are happy to supply articles or information on several aspects of Environment in Construction including:


  • Water usage and wastage.
  • Land and impact damage.
  • Carbon Emissions and U Values
  • Sound in Buildings
  • Insulation
  • Earthquake and Construction (ERD)

Chris Thorpe

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