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Energy Celebrity visits site!
The West-London low energy community was all-a-flutter recently at the visit of Professor David Mackay to our build. As well as being DECC’s Chief Scientific Advisor, Professor Mackay also wrote the seminal work on addressing the UK’s energy conundrum - Sustainable Energy, without the hot air. A must read and free to download from his website.
Professor Mackay spent many hours visiting our site, another one of our (very similar) projects up the road and the windows workshop. As well as discussing a range of impressively technical (and sometimes frankly indecipherable) questions with our engineers, Professor Mackay also found time to query whether the insulation would be irresistible to rodents for nesting…let’s hope not!
It was most encouraging that someone with such influence over UK energy policy has the time and inclination to visit projects that are actively addressing low energy retrofits. Converting our solid-wall housing stock into buildings that will keep people warm without having to pour heat into them constantly (current practice) is a massive practical challenge, one that will need proven, practical know-how, so it’s just as well those responsible for deciding how we proceed are genuinely keen to harvest as much of it as they can.

Energy Celebrity visits site!

The West-London low energy community was all-a-flutter recently at the visit of Professor David Mackay to our build. As well as being DECC’s Chief Scientific Advisor, Professor Mackay also wrote the seminal work on addressing the UK’s energy conundrum - Sustainable Energy, without the hot air. A must read and free to download from his website.

Professor Mackay spent many hours visiting our site, another one of our (very similar) projects up the road and the windows workshop. As well as discussing a range of impressively technical (and sometimes frankly indecipherable) questions with our engineers, Professor Mackay also found time to query whether the insulation would be irresistible to rodents for nesting…let’s hope not!

It was most encouraging that someone with such influence over UK energy policy has the time and inclination to visit projects that are actively addressing low energy retrofits. Converting our solid-wall housing stock into buildings that will keep people warm without having to pour heat into them constantly (current practice) is a massive practical challenge, one that will need proven, practical know-how, so it’s just as well those responsible for deciding how we proceed are genuinely keen to harvest as much of it as they can.




Oakey Dokey
Today’s blog should rightly be about The Windows Problem and Consequent-Month-Delay-To-The-Project - Aaaagh!!! But I’m hoping that if I ignore that, it will resolve itself…
So instead, I’m going to concentrate on the positives. Our wood floor is in and looks beautiful.
Wood flooring can be a very eco-friendly option as it is durable, renewable and takes little energy to produce. However, it can also be a very bad option if you choose a wood that is not from a sustainably managed forest. Trees suck up carbon dioxide as they grow and release oxygen back into the atmosphere. If a forest is harvested for wood which is not replaced, the carbon dioxide that was previously locked up is released and there is less forest left to continue absorbing carbon dioxide from the atmosphere. There are also associated problems of threats to biodiversity, soil stability etc.
You can go some way towards lessening the impact of your wood floor choice by restricting the source country of your wood (i.e. European sources are generally a safer option as forests in Europe are protected by legislation which requires a minimum requirement of replacing trees that are harvested and limiting volumes that can be harvested).  However, that is not necessarily a foolproof approach.
The best way to ensure your wood is eco-friendly is to look for certification which tells you your wood is from a sustainably managed source. The most reliable certification scheme is offered by the Forest Stewardship Council (FSC).
The wood we have ended up with is solid board oak from The Natural Wood Floor Company (NWF):
1.       Eco-credentials
The oak provided by NWF is sourced from a sawmill in Romania which is FSC certified (we checked this out on the FSC’s certification checker.) In addition, the NWF promises that “a strict policy is followed throughout the manufacturing process to ensure that the company’s products are produced with minimal impact on the environment. [NWF ]operates a zero waste policy throughout the whole production process… The entire tree trunk is used … By-products, such as sawdust and bark, are then used to power the wood drying kilns, as well as to heat the factory buildings. Anything leftover is made into bio-fuel and sold.” So that all sounded pretty good to us.
Price
We looked at a few wood flooring providers in the London area and none could compete with NWF in terms of price, except for ones which sourced their wood from China without certification (and therefore raised questions about sustainability), and ones which could only offer narrow widths (i.e. less than 150mm). The price we paid was £28 (exc VAT) per square metre for unfinished 175mm-width planks of solid board oak. For that price, we are expecting to last forever!

3.       Style

Lovely simple wide-board oak. What more could you want?

Okay, so we played it a bit safe style-wise. We did toy with two alternative ideas which might have been a bit more radical. One was using reclaimed wood and the other was using bamboo (which is, botanically speaking, actually a grass rather than a wood). However, we discounted reclaimed wood because of lack of time – it requires a bit more hunting around for the right batch and is generally trickier to install (although no doubt it a very rewarding search to do if you have time as you end up with something unique and with its own special history). Bamboo we discounted because we were not entirely convinced by the narrow-striped look of it, although no doubt in the right context it is looks great

Right now, we are just enjoying the fact that, in spite of other delays, some things are continuing to come together. Even if it means we will be camping in a window-less shell with a newborn baby and toddler, at least the floor we are sleeping on will be lovely.
 PHOTO - as far as we know, this isn’t the tree that our floor comes from, rather a pic taken from flickr…if you’re the photographer and object, please let us know!

Oakey Dokey

Today’s blog should rightly be about The Windows Problem and Consequent-Month-Delay-To-The-Project - Aaaagh!!! But I’m hoping that if I ignore that, it will resolve itself

So instead, I’m going to concentrate on the positives. Our wood floor is in and looks beautiful.

Wood flooring can be a very eco-friendly option as it is durable, renewable and takes little energy to produce. However, it can also be a very bad option if you choose a wood that is not from a sustainably managed forest. Trees suck up carbon dioxide as they grow and release oxygen back into the atmosphere. If a forest is harvested for wood which is not replaced, the carbon dioxide that was previously locked up is released and there is less forest left to continue absorbing carbon dioxide from the atmosphere. There are also associated problems of threats to biodiversity, soil stability etc.

You can go some way towards lessening the impact of your wood floor choice by restricting the source country of your wood (i.e. European sources are generally a safer option as forests in Europe are protected by legislation which requires a minimum requirement of replacing trees that are harvested and limiting volumes that can be harvested).  However, that is not necessarily a foolproof approach.

The best way to ensure your wood is eco-friendly is to look for certification which tells you your wood is from a sustainably managed source. The most reliable certification scheme is offered by the Forest Stewardship Council (FSC).

The wood we have ended up with is solid board oak from The Natural Wood Floor Company (NWF):

1.       Eco-credentials

The oak provided by NWF is sourced from a sawmill in Romania which is FSC certified (we checked this out on the FSC’s certification checker.) In addition, the NWF promises that “a strict policy is followed throughout the manufacturing process to ensure that the company’s products are produced with minimal impact on the environment. [NWF ]operates a zero waste policy throughout the whole production process… The entire tree trunk is used … By-products, such as sawdust and bark, are then used to power the wood drying kilns, as well as to heat the factory buildings. Anything leftover is made into bio-fuel and sold.” So that all sounded pretty good to us.

  1. Price

We looked at a few wood flooring providers in the London area and none could compete with NWF in terms of price, except for ones which sourced their wood from China without certification (and therefore raised questions about sustainability), and ones which could only offer narrow widths (i.e. less than 150mm). The price we paid was £28 (exc VAT) per square metre for unfinished 175mm-width planks of solid board oak. For that price, we are expecting to last forever!

3.       Style

Lovely simple wide-board oak. What more could you want?

Okay, so we played it a bit safe style-wise. We did toy with two alternative ideas which might have been a bit more radical. One was using reclaimed wood and the other was using bamboo (which is, botanically speaking, actually a grass rather than a wood). However, we discounted reclaimed wood because of lack of time – it requires a bit more hunting around for the right batch and is generally trickier to install (although no doubt it a very rewarding search to do if you have time as you end up with something unique and with its own special history). Bamboo we discounted because we were not entirely convinced by the narrow-striped look of it, although no doubt in the right context it is looks great

Right now, we are just enjoying the fact that, in spite of other delays, some things are continuing to come together. Even if it means we will be camping in a window-less shell with a newborn baby and toddler, at least the floor we are sleeping on will be lovely.

 PHOTO - as far as we know, this isn’t the tree that our floor comes from, rather a pic taken from flickr…if you’re the photographer and object, please let us know!

Painful paint

This week we dipped into the world of “eco-paints” in an attempt to find the best solution for our house. It is not an easy process. There are lots of brands making lots of claims that fall under the broad category of “eco-friendly”, but without doing a Phd on the subject, it is incredibly difficult to compare. Sorry that this post is so long, but hopefully it will be interesting/helpful.

The main reason seems to be what counts as being “eco”. Some paints, eg Earthborn, concentrate on the impact of their paints on the living environment of the user compared to traditional paints. The argument here is that conventional paints can release harmful chemicals into the air, whereas Earthborn’s “natural” paints are water based and contain no VOCs* (the real bad boy in paint) or acrylic softeners.

However, even if these claims are sound (I say this because there is sporadic debate about whether the alternative ingredients of “natural” paints also have a harmful effect on health and the environment), they don’t drill down into other considerations such as the carbon emissions of the manufacturing process.

Also, on another point, without buying and testing a million different pots of paint from each brand (which wouldn’t exactly be eco-friendly), it is impossible to get a thorough comparison of how the different brands compare with one another in terms of opacity and durability. Clearly, even if a paint scores highest in terms of eco-friendliness on a litre by litre basis, if you need to buy a whole lot more litres to do the job, or if the paint lasts only the half the time of one of the competitor brands and needs to be replaced, its high score gets chipped away.

So, somewhat reluctantly, we accepted that without being able to compare reliably, we were not going to find a clear winner. Instead, we decided to go for a brand which appeared to tick as many boxes as possible.

Our choice is Dulux’s Ecosure range. This feels like a cop out but that may just be because of inherent doubts around big mainstream providers jumping on the green bandwagon with token offerings and lots of greenwash… However, putting our natural scepticism to one side, we think that the Ecosure range fares pretty well against out key criteria:

  1. Eco-credentials: 
  • Almost zero VOCs. According to Dulux “no organic materials such as solvents are added in the manufacture but some of the raw materials that are used can contain traces of volatile components which is why this figure can never really be absolutely zero.”
  • 35% less embodied carbon. This was based on analysis of the lifecycle of the new range, developed in conjunction with the sustainability charity Forum For The Future, compared with the standard Dulux Trade range, from extraction, growing and re-processing of raw materials to the manufacturing process itself. What we couldn’t find were the actual figures showing what the embodied carbon was reduced to or from.
  • Packaging contains 25% recycled plastic
  • “High opacity provides excellent coverage and application” (we couldn’t test this claim, but Dulux produces some charts showing high performance compared with unnamed “eco brands”.  Presumably we will find out as we start to use it…
  1. Price

The Ecosure range is more expensive than standard Dulux paint, but probably broadly comparable to other eco brands, although it is difficult to assess as you need to take into account average coverage of the paint as well as the cost per litre. For comparison, the Ecosure is approximately £10 more expensive per 5 litre pot than standard Dulux matt emulsion.

  1. Style

The easiest sell for Dulux is the beautiful colour charts they have. “Greenness” is all very well, but other colours are very important too! Unfortunately, none of the other eco brands that we were looking at could offer us a showroom at the end of our road with a library of beautiful colours and a stool to rest a weary pregnant body on…. I fear this may be the main reason we ended up with Dulux, but please don’t judge me.

It is a bit unfair to judge Dulux above other green brands on this element, as some of the other brands we came across said that they would match any colour, but in terms of ease and practicality, this where mainstream providers do come into their own.

Some more options

In order to give a bit of balance, there were a few brands we came across that looked great, responded promptly to our queries, and appear to offer a good spread of colours. If we had the time and tools to do a proper comparison of their products against the Ecosure range, we suspect they might have done rather well:

  • Paint The Town Green – who manufacture their paint in a “green” factory in Iceland which uses hydro-electric and geo- thermal power.
  • Auro paints – whose ingredients are sourced as locally and ethically as possible and whose factory uses wind power and solar energy to help with energy supplies and rain-harvested water for washing down machinery.

Anyway, enough talking, we need to get on slapping some paint on the walls asap if we’re going to get into this house any time soon.

 

*NB it should be pointed out that there is new legislation in effect which means that from 1 January 2011, VOCs levels in paint will be subject to certain restrictions depending on the particular use to which the paint is being put. There is more information here.

The Team!
This is our great team of builders. They have risen to the many challenges of the build with remarkable calm, resourcefulness and skill. Not a single member of the team has been anything less than exceptionally talented and hard-working. And perhaps most amazingly of all, they are all very very nice people.
There are a couple of people in this photo, who I will certainly write about individually because they are so impressive and instrumental to the success of this project.

The Team!

This is our great team of builders. They have risen to the many challenges of the build with remarkable calm, resourcefulness and skill. Not a single member of the team has been anything less than exceptionally talented and hard-working. And perhaps most amazingly of all, they are all very very nice people.

There are a couple of people in this photo, who I will certainly write about individually because they are so impressive and instrumental to the success of this project.

THE WINDOWS ARE COMING (AT LAST!)

It’s fair to say that there have been many technical challenges in bringing this project to fruition, though perhaps none more testing than producing triple glazed sash windows that are thermally efficient and pass stringent planning regulations.

Being in a conservation area, the windows have to be “similar in appearance” to existing sash windows - i.e. look pretty much exactly like a traditional sliding sash, including being made of wood. It just so happens that nobody makes triple-glazed windows like this, so we had to it ourselves…

The challenges are multiple and onerous, including:

  • achieve whole window U-values of 0.9 at least,
  • carry the weight of triple glazing in a sash structure, and
  • achieve sufficient levels of airtightness

In some ways having to start from scratch has been an advantage as we have been able to work from a blank canvas. Some exceptional design and technical brains have been deployed throughout the process.

The end product is a sash lookalike, with a fixed upper pane and tilt-and-turn lower section. With a triple seal, this results in excellent airtightness and allows us not to have to overly beef up the central bar to carry the weight. It also makes the window easy to clean and allows passive ventilation without compromising security.

I know these are not the most amazing pictures, but I guess they may be of interest to machine/carpentry geeks. And who knows, perhaps this is just the beginning of a bit of the fabled low carbon economy here in little old West London…?!

PAINT THE HOUSE GREEN
As the skin and bones of the house begin to fall into place, we are turning our attentions to the prettier side of things - i.e. the decoration.
Given our limited budget and tight timetable (baby due in 7 weeks), we may not get as far as sourcing ethical napkin holders at this stage, but rather will concentrate on the plain old underwear of the house: paint, flooring, work surfaces etc.
There is masses of information, not to mention masses of greenwash, on the internet about environmentally-friendly decoration, so it is dangerous territory we are entering.
Worktops
One area where we do think we may have struck gold is on kitchen worktops. There I was getting bogged down in all the pros and cons of the traditional products: granite, stone, corian, concrete etc, when along popped two extremely exciting and attractive products: recycled glass and recycled plastics.  I got cold feet about the recycled plastics fairly early on into my research as they were too challenging for my conservative taste and, probably unnecessarily, I felt slightly nervous about them releasing toxins into the purity of our air-tight house… if you want to look into this yourself, the company we came across is www.smile-plastics.co.uk. So, glass is our main contender. Time for a quick check against our three criteria:
Eco-credentials:
Glass worktops supplied by GLASSeco are made from 89.4% recycled materials. The glass used is 100% recycled post-consumer waste, including bottles, jars and mirrors. So instead of mouldering away on its own in the purgatory of a landfill site, a bottle that makes its way into a recycled glass worktop is essentially given a ticket to a new life of usefulness and beauty. It is also a One Planet Product, which measures various factors including lifecycle, but we have not had time to check this.
Price 
Okay, so this is not the cheapest solution in the world, but compared with directly comparable products such as granite or stone, it is at least no more expensive.
Style
The product is undoubtedly beautiful, with great depth and interest. There are lots of different colours to choose from. Our favourite is the classic white, which is simple and stylish, but has flecks of mirror throughout which make it sparkle. If you really want to go to town, though, you can specify your own special blend of materials, get lights in-set into the surface or cast special designs into the surface.
Sorry for the rubbish photo – the best a blackberry camera in our corridor could manage – but if you like the sound of this material, visit www.glasseco.co.uk
We’re hoping to write a bit about paints soon, if we can successfully navigate the utterly confusing world of eco paints…til next time!

PAINT THE HOUSE GREEN

As the skin and bones of the house begin to fall into place, we are turning our attentions to the prettier side of things - i.e. the decoration.

Given our limited budget and tight timetable (baby due in 7 weeks), we may not get as far as sourcing ethical napkin holders at this stage, but rather will concentrate on the plain old underwear of the house: paint, flooring, work surfaces etc.

There is masses of information, not to mention masses of greenwash, on the internet about environmentally-friendly decoration, so it is dangerous territory we are entering.

Worktops

One area where we do think we may have struck gold is on kitchen worktops. There I was getting bogged down in all the pros and cons of the traditional products: granite, stone, corian, concrete etc, when along popped two extremely exciting and attractive products: recycled glass and recycled plastics.  I got cold feet about the recycled plastics fairly early on into my research as they were too challenging for my conservative taste and, probably unnecessarily, I felt slightly nervous about them releasing toxins into the purity of our air-tight house… if you want to look into this yourself, the company we came across is www.smile-plastics.co.uk. So, glass is our main contender. Time for a quick check against our three criteria:

  1. Eco-credentials:

Glass worktops supplied by GLASSeco are made from 89.4% recycled materials. The glass used is 100% recycled post-consumer waste, including bottles, jars and mirrors. So instead of mouldering away on its own in the purgatory of a landfill site, a bottle that makes its way into a recycled glass worktop is essentially given a ticket to a new life of usefulness and beauty. It is also a One Planet Product, which measures various factors including lifecycle, but we have not had time to check this.

  1. Price

Okay, so this is not the cheapest solution in the world, but compared with directly comparable products such as granite or stone, it is at least no more expensive.

  1. Style

The product is undoubtedly beautiful, with great depth and interest. There are lots of different colours to choose from. Our favourite is the classic white, which is simple and stylish, but has flecks of mirror throughout which make it sparkle. If you really want to go to town, though, you can specify your own special blend of materials, get lights in-set into the surface or cast special designs into the surface.

Sorry for the rubbish photo – the best a blackberry camera in our corridor could manage – but if you like the sound of this material, visit www.glasseco.co.uk

We’re hoping to write a bit about paints soon, if we can successfully navigate the utterly confusing world of eco paints…til next time!

SOLAR PANELS IN PLACE

Exciting news - the solar thermal panels are now in place on the roof. There are 3 in total, 2 integrated into the slates on the front roof slope and one mounted on an A-frame on the flat roof.

Planning permission was only granted on the basis that the panels are unobtrusive - we’re rather pleased with the final product and think they look a lot better than the average Velux window.

It will be interesting to see how the system performs given the different shading profile on each panel, especially the top one which is shaded by the huge chimney stack. Time will tell…

FITTING THE CAMEL THROUGH THE EYE OF A NEEDLE

Don’t worry, this is not going to turn into some sort of biblical rant, rather it struck me as an apt description for the challenge of getting the MVHR into the cellar.

At over 2 metres tall and weighing a beastly 250kg, it is going to be a titanic struggle squeezing it down the tiny cellar stairs, pictured.

Any strong and willing West Londoners interested in lending a hand are most welcome!

THERMAL BRIDGING

As the build races ahead, we can look back at the dozens of different techniques and tricks we have used to eliminate thermal bridging throughout the build. The Foamglas structural insulation we use has played no small part, as can be seen from the photos - it is the black brick-like stuff.

Take the kitchen for example - to extend the kitchen outwards we installed a steel frame to support the old wall. This “warm” frame sits inside the thermal envelope, so foamglas was used to insulate it from the cold brickwork above and the ground below.

Next, our first layer of insulation (130mm thick) was mounted on battens and a small membrane used to ensure the integrity of the airtight layer.

This left the insulation standing 20mm (or one batten’s width) away from the foanglas, so be sure of closing off the bridge we filled the bottom of the cavity with polystyrene beads. This keeps the thermal skin around the building completely unbroken.

In a different area, we insulated over the top of a suspended floor (which we lowered specifically for this purpose). This meant that any stud walls resting on this suspended floor had to sit on top of a foamglas plinth, which in turn had to be sealed to the OSB with special tape to keep the integrity of the airtight layer.

With a loft extension, kitchen extension, bay windows and a floor that is part basement, part suspended floor and part slab, this build does not have the geometrical simplicity that most Passivhaus designs espouse. This has meant literally dozens of highly complex details must be prepared to cut off thermal bridges and potential air leakages at every single junction, interconnection and corner in the house…

It makes for a lot of work!

"PREPPING" THE AIR

By “prepping”, I mean pre-heating or pre-cooling, but couldn’t think of a word to describe those two things at the same time…any suggestions on a postcard please.

I’m going to tell you now about an exciting little innovation that we have built beneath the cellar of the house - a labyrinth heat exchange! Because the temperature more than 1 metre underground remains at a constant 12(ish) degrees centrigrade all year round, we are able to use it to pre-heat our air before it comes into the MVHR; or cool it in summer.

Low level heat energy from beneath the earth is used in many contexts, but when we were designing the house, we did not find an example of it being installed in a cellar. This is interesting because there are plenty of properties with cellars/basements, but no gardens, for whom a cellar heat exchange could be a helpful energy source.

Including the 6 metre long inlet pipe that brings air in under the kitchen floor, there are 28m2 of surface area for the air to come into contact with before entering the MVHR. We have placed various sensors to measure incoming air temperature (i.e. temperature outside), ground temperature and the temperature of the air when it comes out of the heat exchange. We haven’t turned the MVHR on yet, and anyway it hasn’t exactly been cold, but we are hoping that the labyrinth heat exchange will bring the incoming air up to 12 degrees in the winter, or down to 20 degrees in the summer.

We have addressed condensation issues by sloping the surface inwards to a central drain channel, which runs to a sump.

It is insulated on top and now all covered up, so let’s hope it works because I don’t want to have to take the floor up to fix it!