Designing an eco home is as much about working with your natural surroundings as it is about planning to use the right materials for your building In this book, Christopher Day draws on his extensive experience to explain the key principles of eco home design, focussing on natural methods rather than expensive technology Beautifully illustrated, it highlights how aesthetics, comfort, and economy arise from eco responsible design theyre not add ons, nor are ecology and art in conflict This book will give you essential guidance in working with your surroundings understanding what you can do yourselves and ecobuilding without relying on technology Good clear explanations Unfortunatley jobs added to my husbands to do list Great book My training and profession makes use of understanding of the natural sciences, Physics in particular, and I am trying to make ecologically sound and energy efficient improvements to a 1920s house I also like practical, earthy guides to home improvement and building, as I m susceptible to paralysis by analysis I therefore devoured this book with great interest and I am certain that it will guide and inspire ongoing and future projects in my home and garden Unfortunately, there s the significant problem that the entire book is riddled with errors mostly minor ones of physical units or typos but also serious errors and omissions in the explanations of the physical processes that are supposed to underpin the advice within.This is a great shame I have every reason to believe that Christopher Day is offering a wealth of practical knowledge acquired over decades of trying, doing, failing and correcting Just the kind of hands on knowledge that you d want if starting out in an eco home build or renovation I also appreciate that he s not a scientist and much of what he states is just repetition of commonly held misconceptions but all it would have taken to put this fine book on the right track would have been a proof reading from a qualified physical scientist.Examples include the statement that humid air conducts heat faster than dry air This just isn t supported in the scientific literature and in fact the opposite is true at the kinds of temperatures and relative humidity we live in Further on, there s the simply wrong statement that negatively ionised air molecules lack electrons that would make them positively charged and a host of other comments that would make anyone relying on science to inform their decisions feel rather queasy.Then there s the near criminally inaccurate comparison of the energy efficiency of heat pumps He rightly states that they are a means of getting around three units of useful heat energy for each unit of electrical energy by extracting heat from the surroundings and also correctly states the conversion efficiency of electricity of around three units of primary fossil burned energy to produce one unit of electricity He then multiplies the two factors together and states this made a net efficiency of 1 1, so they were in effect useless The logical problem here is that heat pumps should only considered in comparison to other electrical heat generation methods such as underfloor heating, storage heating or water tank immersion coils By comparing with these, the three for one factor is self evidently important and any on or off grid electrical generation that is done sustainably results in massive improvements in efficiency So, for example, if you had a PV roof panel or wind turbine generating electricity and wanted to use some to heat your home, then using it to drive a heat pump would make great sense, all else being equal.I am also irritated by the inherent suggestion that anything natural is safer and less toxic than anything synthetic While I happily agree that traditional natural materials are hard to beat and that we have introduced some awful toxins into our living spaces through man made materials and coatings, it s this kind of statement that drives non critical thinking in building design An extreme example is that I could spend 15 minutes in a local forest and find a plethora of natural toxins that could kill you but a relevant example in the context is that inhalation of wood dust hardwoods such as oak and sequoia in particular has been linked with nasal cancers in woodworkers Nature is full of evolved mechanisms to protect itself and plenty of other coincidentally dangerous properties Resist the marketing nonsense that equates natural with safe and healthy even if they often go hand in hand Don t get me wrong I completely endorse Day s holistic and human approach to architecture and design, considering the living system the home and its occupants in multiple aspects It s fantastic to consider the interaction of trees and plants in your garden with the conditions inside your home throughout the year it s true wisdom to point out that hermetically sealed airtight homes are at risk of air pollution and lack the stimulus of changes in air and temperature around the home I just wish he could have done this without resorting to what the skeptics call woo woo It s a real shot in the foot for an otherwise enlightening book.Ultimately I m conflicted by this title As a person who chooses hand tools over powered ones for sawing, chopping and stacking wood for my log burner who lays hedge rather than puts up panel fencing who throws on another sweater to relax in rather than sticking on the central heating I embrace so much of what Day writes here and thank him for penning a book full of hard learned wisdoms On the other side, as person who trained in the physical sciences and works in high tech engineering, I am disheartened that publishers think it s OK to put out a book with section headings of Building physics and Thermal Mass without asking a qualified critical technical reader to check the copy Green Books has their postal address in Cambridge and as I live there I can assure you that there are plenty of people around who would have done this job free or nearly free me included In fact, I invite the publishers to contact me if they want a list of the technical errors I noticed as I turned the corners down on each page where this occurred A second edition on a solid physical foundation would be get 5 recommendation from me As it stands, I can t give it than 3 for it s hit often and miss occasionally advice.
- 256 pages
- The Eco-Home Design Guide: Principles and practice for new-build and retrofit (Sustainable Building)
- Christopher Day
- 11 April 2019 Christopher Day