Monday, 14 January 2019

Carbon Fields

The plants of wild flower meadows are adapted to,
and need, grazing Photo: Sue Everett
Belted Galloways grazing marshy pasture in the Kennet Valley
Photo: Sue Everett
This is the title of Graham Harvey’s excellent book, published in 2008, dedicated to the benefits of grazing and grasslands and their role in mitigating climate change and supporting biodiversity associated with grazed and open habitats, such as flower-rich meadows and pastures. However, in recent years livestock farming has been vilified for its role in climate change (e.g. see Livestock’s long shadow - https://bit.ly/2xUdwzu), with the spotlight on cattle in particular owing to their ruminant physiology that results in them belching copious quantities of the greenhouse gas, methane. Last year a new metric for calculating methane’s global warming potential was published (acronym GWP*) which more accurately reflects its climate impact and short life (it is broken down by natural process in about 12 years). Methane does not accumulate in the atmosphere, unlike CO2, therefore reductions in livestock numbers and corresponding falling methane emissions will result in falling levels of the compound in the atmosphere, leading to cooling. Applying this metric and taking into account the role of extensive livestock in building soil in permanent grassland, will give more positive carbon accounts to extensively grazed pasture-lands. Climate metrics for ruminant livestock has been issued by researchers at Oxford University and can be downloaded from https://bit.ly/2MbVNH2. See also Christine Page’s blog from Smiling Tree Farm in Shropshire (Carbon Mooves - https://bit.ly/2J4mpvC), the many contributions from Simon Fairlie in The Land magazine (www.thelandmagazine.org.uk) and Simon’s book Meat a benign extravagance.

At the end of the day the clear focus for emissions-reductions must be fossil fuels - which provide much of the energy used to support growing crops for intensive and environmentally-damaging livestock production. Reducing dietary consumption of intensively-farmed meat, and to a lesser
The Large Blue Butterfly requires
closely-grazed flower-rich limestone
pasture, where it's larval foodstuffs,
Wild Thyme and the grubs of red ants,
can thrive
  
Photo: PJC&Co, Wikimedia
extent dairy, can obviously be an important driver for reducing the most environmentally-damaging kinds of farming. In contrast, extensive pasture-fed livestock are powered primarily by the sun and provide the engines for maintaining some of Europe's most fabulous high value nature sites - from Devon's Culm Grasslands, to the Grand Causses in southern France and the high mountain pastures in the Pyrenees. So for those of us who choose not to be vegan, 'eating the view' and 'slow food' are the ways to go.

This article is a preview of a small part of the February edition of Conservation News which I compile, that will be published in British Wildlife magazine. This magazine is issued 6 times a year and is available by subscription only.


Organisations supporting sustainable grazing for climate and biodiversity include the Pasture Fed Livestock Association, European Forum on Nature Conservation and Pastoralism, the Agricology initiative, Nature Friendly Farming Network and the Wales Grazing Animals Project.

Monday, 12 February 2018

Wednesday, 15 November 2017

Which way for Glyphosate?

Version 1711/17

I've just done some research into the world's most commonly used herbicide - Glyphosate. Admittedly, there's many limitations on what I've done. For example, I have not looked at other than one study into the adjuvants (chemicals used in the commercial herbicide formulations to assist application) nor at the huge number of reports on food residues. Some of the adjuvants are considered to be of greater toxicity than glyphosate itself - I’ve written about these before in my Conservation News column in British Wildlife.

A complete document with references (bear in mind it's not 100% tidied up as I've run out of time to do that right now) is available, let me know if you want to see it. I'm also happy to update what I've done with missing info and to correct any errors. 

If you manage to get to the end of this blog, let me know what decision YOU would make on whether to relicense it for use in the EU - a decision which will be made at the end of this month (November 2017).

My interest in the subject is because I want to understand more about glyphosate-based herbicides (GlyBH) and their actual and potential effects on human and environmental health, including on soils. I have used Roundup® - the original formulation marketed exclusively by Monsanto until recently - personally and professionally. It’s very useful, for killing weeds growing in the patio, knackering bindweed in the allotment and extremely helpful when establishing new wild flower grassland on arable or other bare ground.


One of the claimed for ‘vital’ uses for GlyBH is in the increasing adoption of minimum tillage, which means that farmers no longer need to plough arable land, but can direct drill the next crop into soil that has been cleared of weeds using glyphosate. Minimum tillage is considered to be beneficial to soil conservation by reducing erosion by water, wind and oxidation. In the UK there is a campaign among conventional farmers, led by the National Farmers’ Union, for Glyphosate to be relicensed by the EU (#GlyphosateisVital) - a decision which should have been made November, but a qualified majority vote could not be reached on the proposal to issue a new licence for five years. The European Parliament had previously voted by significant majority to phase out the herbicide completely for agricultural use by 2022 and to ban household use immediately. A decision by the European Commission will now have to be made by the Appeal Committee by November 2017.

GlyBH have been used since 1974 and while their use has escalated across the world over the past two decades there remain significant gaps in our knowledge of the risks the herbicide poses to people, soils, air, water and nature. Research into its role and benefits, such as for rebuilding soils under minimum tillage, has also been neglected - meaning that claims on its usefulness for this purpose are not adequately supported by peer-reviewed evidence.  Making a reasoned decision on whether this useful herbicide - one which agriculture currently relies upon - and which some say is a vital tool for producing food under current ‘conventional’ farming systems (and for other purposes such as invasive weed control) - should be banned across Europe, is what might some would call a wicked conundrum.

Here's a summary of what I found out (or in some cases knew already through my work as a land management adviser):


  1. USE. GlyBH are widely used across the UK on farms, parks, gardens, along roadsides,around buildings and to keep the railways clear of weeds.
  2. FOOD RESIDUES.
    1. Glyphosate residues are found in many samples of food consumed in the UK but are also not present in many food samples. However residues, where found, are generally well below the permitted Maximum Residue Levels.
    2. Sampled foodstuffs often contain multiple pesticide residues. We have no knowledge of the synergistic effects of these on human health.
  3. HERBICIDE RESISTANCE.
    1. GlyBH are relied upon in conventional arable farming to destroy infestations of herbicide-resistant black grass that have arisen partly because GlyBH have facilitated changes in farming practice.
    2. Although glyphosate-resistant Black Grass is not yet a problem in the UK, many consider this is only a matter of time, especially as farmers now rely on GlyBH for conservation tillage.
    3. Glyphosate-resistant weeds are a massive problem in countries where glyphosate-tolerant genetically-modified (GM) crops have been/are widely grown. Some of those weeds are already present on UK farms.
  4. LAND TRANSFORMATION.
    1. GlyBH (along with other changes, such as larger and more powerful farm machinery) have made it easy to transform previously diverse mixed-farmed landscapes, with adverse indirect and direct impacts on soil, nature and freshwaters.
    2. This transformation has also contributed to increased flooding of settlements as it has encouraged the cultivation of unsuitable land that is at high risk of water erosion.
  5. USE IN ECOLOGICAL RESTORATION.
    1. GlyBH are commonly used in ecological restoration, such as the re-establishment of flower-rich grassland on bare land, for weed control in hedge and tree planting and for killing invasive species such as Japanese Knotweed.
    2. It is currently the main tool for controlling/eradicating some non-native invasive species, such as Japanese Knotweed. If banned, other herbicides would instead need to be used to control some of the UK’s worst invasives such as Japanese Knotweed.
  6. SOIL and WATER.
    1. A recent study found residues of glyphosate and its metabolite, AMPH, present in European soils. However, there is no long term, systematic monitoring programme of this herbicide in the soil environment.
    2. Glyphosate and AMPH have been found in a large proportion of sampled water bodies, but there are no water quality requirements for the substances and no ongoing monitoring programme for them.
    3. Currently, minimum tillage practiced by most non-organic farmers is reliant on using GlyBH. There is some evidence that minimum tillage increases soil carbon and biodiversity, reduces water erosion and rebuilds topsoil and that it also reduces GHG emissions owing to the reduced amount of fuel used compared to a conventional plough-based system. However, to quantify and scientifically validate these claimed-for benefits, a systems-based long term research programme on minimum tillage systems is needed - with and without GlyBH.
    4. Evidence on the long term impacts and potential side-effects of pesticides, including glyphosate, on non-target soil organisms, is thin. A recent study found adverse impacts on the surface casting activity of vertically burrowing earthworms and the reproductive capacity of some soil fauna, plus large increases in soil nitrogen and phosphate - suggesting an increased risk of nutrient leaching to ground and surface waters. Effects on nutrient cycling had been identified previously.
  7. HUMAN AND ENVIRONMENTAL HEALTH.
    1. There are significant concerns for human and environmental health regarding the widespread and common use of GlyBH in conventional agriculture across the world.
    2. Human exposures to GlyBH are rising.
    3. Concerns for public health are not confined to potential links to cancer, that have recently been discounted by the European Food Safety Agency.
    4. Risk assessment methodology for this and other pesticides has been criticised by some scientists as being insufficiently robust.
    5. RoundupⓇ has been found to be 125 times more toxic than glyphosate while adjuvants found in GlyBH have been assessed as being 10,000 times more toxic than glyphosate itself.
    6. Recent studies have identified adverse impacts of glyphosate on honeybees.
    7. According to the European Chemicals Agency, glyphosate is not proven to be carcinogenic, mutagenic or to negatively affect reproduction (e.g. reduction of fertility or occurrence of malformations), but it can cause serious eye damage and exert toxicity on aquatic biota, with long-lasting effects
    8. Long term, systematic, field-based research is lacking that would enable us to fully understand the use, fate and impacts of GlyBH at the landscape-scale, in the environment and on people.
    9. There are calls for safety standards for GlyBH to be reviewed and updated as “they may fail to protect public health and the environment”.

Wednesday, 26 July 2017

100 priority questions for landscape restoration in Europe

How can biodiversity and ecosystem processes be restored to degraded landscapes across Europe at a time when there are profound changes of many kinds, from climate change to social and economic upheavals? Please send your questions by 10 August 2017 - read guidance below first. Thanks!

Background
Academics, practioners and policy analyists are repeating a research-agenda-setting exercise to identify the 100 priority research questions, that will help shape research to inform policy and action over the next decade.


Restoring biodiversity and ecosystem processes to degraded areas is recognised as an important part of conservation strategies. The Convention on Biological Diversity Strategic Plan aims to restore 15% of degraded land by 2020 (Aichi Target 15), a goal reflected in the EU’s Biodiversity Strategy (Target 2). Recent reviews have identified habitat fragmentation as a major cause of biodiversity loss in Europe, and recommended landscape-level approaches, based on creation of ecological networks, to help halt and reverse biodiversity decline.

Through this exercise the aim is to identify the questions which, if answered, would make the most difference to the restoration of European landscapes. Questions should be relevant to European landscape restoration, and may relate to areas including, but not limited to: policy, culture, economics, equity, sustainable development, governance, planning, connectivity, reintroductions, climate change and resilience, ecosystem services, or habitat management.

Links to the output of the previous exercises carried out in 2006 are here and in 2008 here 

Framing your questions - guidance
Please send your questions to me at conservation.news@gmail.com with "Landscape Questions" in the subject header. Please provide your full name, any affiliation and phone number.

In order to be a contender for the final list, it is important that questions satisfy a number of criteria. Please ensure that questions:

·         Are answerable through a realistic research design.
·         Have a factual answer that does not depend on value judgments.
·         Address important gaps in knowledge.
·         Are at an appropriate spatial and temporal scale and scope
o   Not too general: i.e. a research programme could make progress towards answering each question. Questions such as ‘How could we improve forest restoration in Europe?’ are too general.
o   Not too limited in scope: i.e. answering a question should have a significant impact on the effectiveness of landscape restoration. For example, questions about the specific ecology of a single species in a particular place might not have enough wider significance.
·         Fall within the scope of the exercise
·         If related to impacts and interventions, contain a subject, an intervention, and a measurable outcome.






Tuesday, 19 April 2016

Wising up on land use and adaptation - more musings on flooding

This post was written at the end of the 2014-15 winter. Since that time parts of the UK experienced yet another "wettest period on record" with widespread flooding in the north of England during December and January 2015-16.

The record-breaking wild, wet and windy winter of 2014-15 was probably a game changer for many reasons. The onslaught of storms fired a series of warning shots showing what climate change probably has in store for us. Serious and prolonged flooding, especially in the Somerset Levels, where about 6,500 ha (c.10% of the area) was under water for several months, and along the Thames in Berkshire, revealed a paucity of resilience at all levels. Despite having successfully defended many thousands of properties from flooding this winter, the Environment Agency became the scapegoat, blamed for allowing the flooding to occur because of something it hadn't done, or in some cases, had done (such as creating the Jubilee River which successfully protected Maidenhead from flooding). It received (in my view) an undeserved kicking from many individuals and some politicians for failing to dredge rivers or install sufficient flood defences, when it has been forced by Government to making swingeing cuts, affecting front line staff and capital expenditure. Further cuts of 1550 staff are planned for the coming financial year, although the flooding crisis has put a consultation on this temporarily on hold.

In the Somerset Levels, where the clamour for river-dredging has been particularly loud, it was subsequently revealed that the EA had agreed that some dredging was needed, but didn't have enough money, while local authorities had refused to contribute. Meanwhile, in recent years, the same local authorities have granted planning permission for new houses in areas that were under water for several months. Andrew Gilligan, writing for The Telegraph, reveals that land next to Curry Moor had also been designated by Taunton Deane Borough Council for new homes while "the neighbouring council, Sedgemoor, had identified sites in at least four villages for housing, even though all are within the highest-risk flood zone". Gilligan also describes the scale of projected housebuilding in areas flooded by the Thames. While most would agree that local authority planning policy is as leaky as a sieve, it is driven by national housebuilding targets and the Coalition Government's dogmatic pursuance of economic recovery based on a stripped-down planning system that has little ability to refuse permission for new homes, even if they are going to be under water within months of occupancy. Government has been a clear and guilty accomplice in the scale of damage caused by floods but the insurance industry is now beginning to call the shots. This is hardly surprising, given the estimated £400m of payouts anticipated from damage this winter and warnings from the UK Climate Change Impact Assessment that nearly 1 million properties are likely to be at risk of flooding during the 2020s. There is no doubt that the Government will continue to support building houses in areas of flood risk, such as at Ebbsfleet (North Kent) where it has announced it is to support the development of a new garden city. The area is considered as being at high risk of tidal flooding.

Magicians Paul Daniels' and Debbie Magee's luxury Thames-side home was one of many threatened by the overflowing river (they kept theirs dry by continous pumping), and they too accused the Environment Agency of causing the severe flooding by failing to dredge the river (thus the water would be instantly magicked away, wouldn't it?). Politicans were caught back-footed, with some (including Communities Minister Eric Pickles, and Somerset MP Ian Liddell-Grainger) behaving in ways that were wholly inappropriate to their status. IL-G, who can at best be described as a baying buffoon, said that EA Chairman Chris Smith   " is a coward, a little git and I'll flush his head down the loo". The TV satire Spitting Image would have had a field day with the lot of them.

The voices of reason from ecologists, hydrologists, engineers, climate-change scientists, the Government's own independent advisers (including the Emvironment Agency and Natural England) and independent commentators, such as George Monbiot, had, until the latter stages of this event, been drowned out by the vociferous minority interests of farmers, the National Farmers' Union and ill-informed politicians (as well as traumatised flood victims) seemingly incapable of taking in the wider picture and the alternative view. However, evidence (much of it collected thanks to Government-funded research, work by the EA, NE and a few water companies) shows that river-dredging and hard defences are out-dated and expensive one-trick ponies that will often not work and in some cases make things worse. For these reasons, engineers and ecologists agree their use should be limited and targeted in places where sufficient evidence is able to show clear cost-benefit. (More on this via G Monbiot here.)

The scale of the damage, from farmland and houses underwater for three months, to the destruction (yet again) of the main coast rail line at Dawlish, and disappearing houses at Hemsby, show that choices will need to be made.  There is not going to be enough cash to defend every vulnerable house, industrial estate, field or farm from the floods, or every crumbling coast from rising sea levels and increasing storm surges. As part of catchment-based flood mitigation plans, and as now indicated in the emerging action plan for the Somerset Levels, water will need to be held back upstream, using ecological restoration techniques and by reversing some of the inappropriate land drainage that causes silt and nutrient-laden soil to devastate land and settlements downstream. This is where the winter storms have become a game changer - upstream measures now have a credible place at the table, helped by the mounting evidence of benefit and greater media coverage given to environmental scientists who can describe what is needed, and warn against what may be unaffordable and unachievable.

On 5 March,  a clear reality check was offered to the Government by Professor Sir John Krebs. Writing to Environment Minister Owen Patterson on behalf of the Adaptation Sub Committee of the UK Climate Change Committee, Sir John offered five key points to consider in relation to Somerset Levels action plan: (1) the plan needs to recognise rising sea levels and flood risk associated with climate change; (2) it should consider the range of drivers operating on the Levels; (3) the plan should be sustainable and cost-effective; (4) it should focus on adaptation and be responsive to new evidence; (5) responsibility for delivering and funding the plan should be shared. In the letter, Sir John makes pointed comments about exploitation of Level's peatlands (which have shrunk as a result and further lowered land levels), the appropriateness of farm subsidies and the need for a review of land-use practices in the catchment. In an interview with The Times (reported in The Western Daily Press) Lord Krebs more explicitly suggested that "It may well be the case that there are areas too expensive to defend". Needless to say, his honesty was not welcomed by either Somerset farmers nor the local MP.

This was preceded, in February, by a letter written to The Telegraph by seventeen professional bodies, representing engineers, ecologists, hydrologists, surveyors, landscape architects, foresters, arboriculturists and other environmental scientists, calling on the Government to act on knowledge and best practice, and have a joined-up strategy for managing water, to include soft-engineering solutions. Growing experience in such techniques, such as piloted in Exmoor and at Pontbren, shows that farming and ecological restoration are not mutually exclusive, although there will certainly need to be a major rethink about intensive farming practices that are causing soil erosion and unacceptable levels of runoff. The dialogue about what to do about this in England has come in the nick of time, as Natural England is putting together proposals for the new environmental land management scheme paid for out of Pillar 2 of the Common Agricultural Policy. This scheme, and a much more comprehensive approach to Catchment Sensitive Farming, could offer the 'carrots' but the stick of regulation will still be needed, coupled with much better monitoring and enforcement of basic environmental protection measures that will act to dissuade farmers from causing significant damage to land and rivers. There is plenty of evidence showing that neither carrots or sticks are working across much of the countryside right now, not helped by the Coalition Government's  wish to strip down regulation, cut back regulatory agencies and let everyone police themselves. In the future farm subsidy cash (up to £200 per hectare) must come with an absolute requirement that those in receipt of it practice sustainable land use. This requirement however, will not be met unless there is a comprehensive extension programme in place with one-to-one advice available, and support for the production of farm- and operations-based environmental improvement plans that farmers and their contractors will need to sign up to.

Back along the coast, the National Trust has already begun to face up to the fact that some of our favourite coastlines are being rapidly re-shaped. Its 2005 Shifting Shores report identified 608km of coastline it owns as being significantly affected by coastal erosion with 169 sites likely to be lost during this century. 10% could lose between 100-200m width of coast, with a further 5% likely to lose 200m or more. This winter's storms also indicate that the rate of loss originally anticipated could be much greater, should such storms become more commonplace. Storm surges in January this year broke up the shingle bank at Spurn Head, where dunes were also completely washed away. The shingle bank, defending the Norfolk Wildlife Trust's Cley Marshes nature reserve in Norfolk was also breached, flooding the reserve and washing boardwalks away.
Langland Beach, Gower, less the sand. M Crafer, Feb 2014.
Most of the sand did come back in 2015, but not all of it.

There were huge strandings of bivalves on The Gower. Local resident and ecologist, Mike Crafer, reported that at least one of the smaller beaches there had disappeared with almost 3m-depth of sand gone. See Patrick Barkham's 7 February column in The Guardian for more opinion on the future shape of Britain's coast.

Experience with both flooding and coastal erosion during the 1990s and to the present, further underline the need for the Government to kick off an honest debate with the public, not only about adaptation, but planning for a future when some vulnerable coastal and floodplain settlements, farmland and nature reserves, will not be able to survive as climate change impacts become more severe. Heritage and conservation bodies have much to lose; in some places they may not be able to gain new ground when long-established nature reserves lose out to either the sea or inland floods. The shape of Britain will change, and so will its wildlife.

Nature-friendly farmers abandoned by Defra & Natural England?


One of my favourite farms in England sits high up (about 1000 feet to be precise) on the limestone above Settle, not far from the world-famous Malham Cove. Lower Winskill is very different from many of the farms surrounding it or elsewhere in the Yorkshire Dales National Park, because it is full of wild flowers that have been encouraged to be at their best (and increase) thanks to the careful stewardship of this land by its owner, Tom Lord. Tom's farm is a beacon of excellence for nature, and his work here has been made possible by 20-years of very special "agri-environment" agreements made with successive government agencies charged with encouraging farmers to do the right thing by nature. Currently, the Higher Level Stewardship Scheme  provides a payment to Tom for maintaining and restoring flower-rich pastures and meadows, and using a variety of livestock species (cattle and sheep) grazed at the right time, to produce the "goods". These include rarities such as Alpine Lady's Mantle and Alpine Cinquefoil as well as plentiful numbers of other flowers, such as Limestone Bedstraw, Cowslip and Devils'-bit Scabious. In summer, his fields are alive with butterflies, including the scarce Northern Brown Argus.

Weed infested flowerless upland limestone grassland
in Swaledale (2015)
These grants have been vital for Tom - without it he would have had to fall into the intensive-farming trap that most others have done and nature would not have been given the chance to remain and recover. A week last year spent walking in the Dales proved how successful he has been; while I visited some stunning limestone landscapes, their grasslands were poor in flowers with too many sheep all over them like a white rash. The pastures had become flowerless for a variety of reasons. Many "free-ranging" sheep for much of the year means a high input of dung and urine - flowers don't like nutrients. Heavy grazing throughout spring and summer also means no flowers, and fewer insects and butterflies as their foodplants are not permitted to thrive. Intolerance of the fox, both associated with sheep-farming and adjacent grouse moors, means too few predators and too many rabbits: their digging and grazing (20 rabbits is the equivalent of one sheep) has no doubt helped the spread of pasture weeds, especially Creeping Thistle. So no surprises then, to see men (no women were seen) out on quad bikes spraying off these weeds in the middle of summer. The herbicides used against thistles also kill other wild flowers - few are species-specific, which many users seem to think they are. So a few years of weedkillers, plus free-ranging sheep that graze off everything during the growing season (and perhaps beyond) means the lovely limestone landscapes (at least the ones I walked across last summer) are practically flowerless. Tom, being a local, will corroborate my description of what's happening on land in the Dales. I might write more on this subject later.

But, back to Tom. He is very cross. After 20 years of using taxpayer's money to maintain and recover nature on his farm he is now told that when his scheme ends next February he will have a year to wait before his land will be entered into a new one. Tom is a dedicated nature farmer, but he cannot afford to carry on without the grants unless he intensifies his farming, and this will be to the detriment of the limestone flowers of his pastures and meadows. Almost his entire farm income after costs is from the Stewardship grants (about £15,000 per year). Tom is not the only farmer or landowner in this position - there are thought to be a large number of others in the same boat, including some national conservation charities such as the National Trust (and probably the RSPB and local wildlife trusts as well). Something similar happened when farmers' Environmentally Sensitive Area Scheme agreements finished; it is widely known that some land that had been supported as hay meadow came out of the scheme and was immediately "improved" to the detriment of the wild flowers that had begun to reappear in them.

The current palaver seems to be two fold: (1) there isn't enough money in the agri-environment scheme "pot" for everyone who needs support at the moment; having a gap between agreements will undoubtedly save the government (i.e. Defra/Natural England) a lot of money and one cynical view that this cost saving was planned for; (2) not all upland farmers with existing Higher Level Stewardship agreements can be "converted" without ease into the new Countryside Stewardship scheme as the latter cannot offer all the same options. There are also other inflexibilities which don't make sense.

So, was this situation arrived at by Cockup (or Conspiracy to save money)? Don't get me wrong - there will be plenty of Natural England advisers on the ground who are mortified by this situation because they see decades of hard graft now abandoned and likely to put High Value Nature areas (that are not legally protected) at risk. No part of Tom's farm is a Site of Special Scientific Interest (although it should be) - as soon as his agreement ends he could talk to the nearest dairy farm and get them to spread slurry all over his beautiful meadows, or just go buy some bags of NPK and tip them across his land. After all that's what's happened to most other flower-rich grasslands in England except for ones on inaccessible slopes; even though farmers are meant to apply for permission to agriculturally 'improve' such areas the regulations covering improvement of uncultivated land are useless and unenforceable. I know, I've tried to use them.

Tom's existing agri-environment agreement ends next February. Let's hope the powers that be sort out something very very soon to ensure that farmers like him continue to be rewarded for doing the right thing by nature.

Thursday, 27 February 2014

Warm work - home insulation

The work described here is part of package of measures being embarked upon, to reduce heat loss from a 1960's semi-detached house in Frome, Somerset. The work has been jointly designed by myself and Paul Buckingham - we are both graduates of the Centre for Alternative Technology Architecture course Advanced Environmental and Energy Studies (PG Dip/MSc).

Before
Top left shows roof plate of my 1960s semi-detached house - uninsulated and with a large area of cold wall inside above all the top floor windows. This is where condensation occurs and mould grows - a problem with all the 1960s houses built to this design.(See my post Save before Generating for more on this.) Windows are below the soffit boards at the base of the roof. Battens attached to the outer blocks support the soffits. The top row of outer blocks is has been used to close up the 50mm cavity.

The picture to the right shows the party wall with an uninsulated cavity that is exposed to the cold where it joins the roof - a major problem. To address it will require pumping insulation in via the internal wall or taking all the roof tiles off to expose and fill it that way. We are exploring the possibility of insulating from inside but have yet to find a company willing to do it. They seem to be few and far between.It is mad that if cavity wall insulation is done (often under a government grant scheme - now it is free to anyone) the party wall is not. As a consequence, this type of house will have only one brick skin between the internal part of the property and the cold winter air.


After
100mm polystyrene insulation has been used - cut in steps up to and including the first 500mm into the loft space. Loft insulation has then been overlapped. An air gap has been left to allow for air to circulate in the roof (inflow via vents in the soffits). Ventilation - moving air - in the roof is vital to prevent condensation occurring in the loft. A section of roof felt had to be replaced with a suitable membrane, although we were able to reuse the battens for fixing the tiles.
Vermiculite was used to fill in gaps between the steps of insulation. The insulation sytem used is Knauf-Marmorit - 100mm polystyrene stuck down with a lime-based mortar (also used to insulate the rear exterior of the house). The down side of this system is the huge quantity of polystyrene waste, and the impossibility of controlling where all the bits go. Despite our best efforts, there are bits of polystyrene all over the place in the garden. With hindsight I would in future prefer to use a wood-fibre product - much more sustainable and environmentally friendly (although nowhere near as good an insulator).

Cavity wall insulation
The house was cavity-wall insulated in 2008, but we know that the insulation did not reach many areas, including under windows and beside doors. Thermal imaging of other properties has shown that insulating cavity walls, especially those with 50mm cavities, is not an exact science. However, leaving bits of uninsulated walls means small areas of cold surface where condensation will readily occur. I have begun the process of seeking restorative work on my property by the company responsible for the insulation - there is a 25-year guarantee.However, they don't seem to be able to find contractors to do the work, as yet.