Modern Methods of Construction (MMC) can be Eco materials

I attended a mortgage lenders conference today at Buildstore on Modern Methods of Construction (MMC) and eco materials; it was great to see almost 100 representatives from lenders and valuers turning up to find out more about better ways to build. On the MMC section SIPS systems, such as foam sandwiched between layers of OSB were mentioned and for Eco, straw bale build and earth ships (car tyres piled up to form a wall) were mentioned. Other conferences & events also still associate ‘eco’ with wacky and very un-conventional building solutions, not that I’m opposed to them. I’ve built straw bale and supplied products on earth ships but never built with SIPS, so on the face of it what’s wrong?

The fundamental understanding of what eco materials really are sometimes needs addressing, yes straw bale is one, so is sheep’s wool insulation and clay plasters but so are engineered wooden triple glazed windows, light weight insulating clay blocks, interlocking wood fibre insulation boards and timber I beams. All of which could be described as Modern Methods of Construction (MMC) products. To me MMC is purely modern methods, or should I say off site construction or integrated building solutions (some of which are very old ideas), but not necessarily eco as I would not put a polystyrene hollow block filled with concrete in the same category as a clay block. To me the environmental impact of the production of a SIPS panel or polystyrene block outweigh any benefits gained in their use and cannot be described as ecological but merely economic, ie cheap solutions, assuming you only consider the energy saving benefits gained by using such products. I try to highlight the risks associated with different manufacturing processes and petro-chemical plants are currently necessary, but pose a high environmental risk so products manufactured in such a way should be minimised where there are suitable alternatives.

Passive House is similar in the context of material selection. High environmental impact materials such as polystyrene & foam insulations along with plastic windows can be used in passive house buildings, as they help achieve the in use energy targets, however somewhat go against the grain of sustainability and low environmental impact. Some say we have to make sacrifices to achieve the carbon reduction targets required to reduce global warming but to me these particular risks are too great, as with nuclear. We should be using MMC solutions that are also ecological in their design & manufacture, and large scale use of wood fibre and clay is perfectly possible and will have a greater impact on the global warming potential of construction. Light weight clay blocks are the main form of building component in mainland europe so most definately scaleable in the UK. Wood fibre is also big business in mainland europe, and could be manufactured in the UK assuming we had a secure feed stock, ie not too many Biomass power stations.

Eco is now most definately in the mainstream conscious,  it's the poeple who still promote the brick and block cavity wall that are wacky!