I've been doing some research recently into the sustainability of building materials and have hit a sort of impass. I wonder if anyone here has any ideas.
let me explain.
looking at the damage that cement does to the environment (see note below) I have been looking at alternatives and find that most of the materials used before cement, as we know it, was invented in the mid 19th century are miles better. especially the use of lime for mortar.
anyway it occured to me that where most of us seem to use cement (in the form of concrete) with absolute abandon is in foundations. when I tried to find out what people did before filling a trench with concrete, there is almost no record apart from some obscure references to using the largest slabs of freestone available, using gravel, and thirdly scorched oak posts.
I suppose it is worth making a distinction here between foundations for large structures and smaller structures such as garden walls, as far as I can tell walls were often built simply by digging down to compacted subsoil and building straight onto it. It seems that some of the flint walls in my area of sussex that are built this way have actually lasted longer than the victorian brick equivalents (mainly due to the brittleness of cement based morter as opposed to the flexibility of lime shingle mixes).
does anyone here have any experience of structures built without concrete foundations? or anyone ever heard of anything useful?
the note about cement?
seems that the government has given the cement industry a few years to clean up its act - the cement industry puts the blame on 'excessive specification' as the problem. but the facts seem to point to the need to find an alternative fairly soon.
why?
in the year 2000 one and a half billion tonnes of cement was used globally. making it the second most consumed commodity after water.
each tonne of cement produces its own weight in CO2 and smaller amounts of highly toxic substances are released into the air.
cement production in the uk accounts for 10% of energy production.
cement cannot be recycled and contributes significantly to landfill.
in the uk cement furnaces are the only permitted users of SLF (secondary liquid fuel). there is an international trade to Britain of SLF because it is the only way of disposing of hazzardous substances that cannot be disposed of in any other way in other EU countries.
shocking eh?
p.s.
Lime, the precursor of cement actually absorbs its own weight of CO2 over a few years, making it one of the few CO2 negative building materials alongside wood.
I appreciate that everyone has an opinion concerning green issues, and each to their own, but I really would like to know more about alternative ways of making foundations. any info gratefully received.
let me explain.
looking at the damage that cement does to the environment (see note below) I have been looking at alternatives and find that most of the materials used before cement, as we know it, was invented in the mid 19th century are miles better. especially the use of lime for mortar.
anyway it occured to me that where most of us seem to use cement (in the form of concrete) with absolute abandon is in foundations. when I tried to find out what people did before filling a trench with concrete, there is almost no record apart from some obscure references to using the largest slabs of freestone available, using gravel, and thirdly scorched oak posts.
I suppose it is worth making a distinction here between foundations for large structures and smaller structures such as garden walls, as far as I can tell walls were often built simply by digging down to compacted subsoil and building straight onto it. It seems that some of the flint walls in my area of sussex that are built this way have actually lasted longer than the victorian brick equivalents (mainly due to the brittleness of cement based morter as opposed to the flexibility of lime shingle mixes).
does anyone here have any experience of structures built without concrete foundations? or anyone ever heard of anything useful?
the note about cement?
seems that the government has given the cement industry a few years to clean up its act - the cement industry puts the blame on 'excessive specification' as the problem. but the facts seem to point to the need to find an alternative fairly soon.
why?
in the year 2000 one and a half billion tonnes of cement was used globally. making it the second most consumed commodity after water.
each tonne of cement produces its own weight in CO2 and smaller amounts of highly toxic substances are released into the air.
cement production in the uk accounts for 10% of energy production.
cement cannot be recycled and contributes significantly to landfill.
in the uk cement furnaces are the only permitted users of SLF (secondary liquid fuel). there is an international trade to Britain of SLF because it is the only way of disposing of hazzardous substances that cannot be disposed of in any other way in other EU countries.
shocking eh?
p.s.
Lime, the precursor of cement actually absorbs its own weight of CO2 over a few years, making it one of the few CO2 negative building materials alongside wood.
I appreciate that everyone has an opinion concerning green issues, and each to their own, but I really would like to know more about alternative ways of making foundations. any info gratefully received.
