Dan and I headed to the Ecobuild conference at the London Excel centre last month. It seemed a good and fun opportunity to research the industry for new and relevant products and to speak to various experts. It didn’t disappoint. Although I was concerned to find that the event appeared quite a bit smaller than when I last attended we did find some really interesting products and were able to make some useful contacts.
The most interesting – and I thought it was a very understated launch given the potential of the product – was a cement-free concrete called Cemfree. Cemfree purportedly uses 95% Ground Blast Furnace Slag (GGBS), seemingly overcoming previous complications when replacing higher percentages of Portland cement. Given the carbon intensity of cement manufacture – regularly cited as being responsible for approximately 5%-8% of global CO2 emissions alone – this is a really exciting development. Cemfree themselves report that their product reduces the carbon legacy of concrete from approximately 312kgs to 31kgs per m3. It would appear to have additional benefits over traditional cement based concrete as well; improved durability, no need for jointing, reduced requirement for reinforcing, improved thermal mass qualities and lower water demand. One further benefit that Cemfree didn’t appear to be pushing but which I think very attractive from a specifying point of view is that its’ natural finished colour is light and present, almost a creamy colour. The premium in terms of price appeared absorbable at a suggested 10% though whether that is accurate in reality remains to be tested. All in all it is a product we will most definitely be investigating. It is a pity a polished concrete floor isn’t perhaps the most practical for house intended to accommodate the elderly otherwise it would be interesting to explore using the slab as the finished floor surface!
Other products of note included a greywater harvesting system with integrated heat recovery called reaqua+ that I’d not come across before. I am much more familiar with rainwater harvesting products than greywater – the former seeming to have established a better reputation than the latter. The ability to reduce water consumption whilst also benefiting from the recovery of heat from greywater is an attractive one. There are still calculations to be run in terms of cost benefit over rainwater harvesting. Rainwater harvesting offers an opportunity to reduce water demand further than greywater recycling. However the shower heat recovery products that I’ve come across are on the whole extremely expensive and simply not worth the investment. The only reasonably priced product, though still not cheap, that I’ve come across is the Zyhpo shower heat recovery system. This combination is likely to be at least £1000 more expensive than the neat and compact reaqua unit, probably more once the additional building costs of burying the rainwater tank are taken into account, so whether it would be worth the investment is questionable. I’ll certainly be running calculations.
There were other finds; some promising contacts in the windows department. Central to the design of the building is a large corner window on the first floor which captures the views right back down the valley. The plan is for the window to be frameless with a butted silicone joint. Finding a manufacturer capable of doing this at a reasonable price is going to be a challenge. It was also interesting to come across the construction system Val-u-therm. This is a closed panel hybrid system encompassing principles of timber frame and structural insulated panel (SIP) systems. I’ll discuss this more in due course but it could be a really attractive option for us. Cladding, flooring, lighting options, the list goes on. All in all a worthwhile visit and I’d recommend to anyone considering or planning their own build.