Why not just fill the cavity, then?

When I've explained our plans to wrap a bungalow in strawbales (even when I just say "externally insulate it") a number of people have asked why we don't just fill the cavity to insulate it.  It's becoming quite irritating, but that's my problem not anyone elses.  It does deserve a proper answer, which sort of serves as an example of what's wrong with general standard construction too.

The rented bungalow we currently live in does have insulated wall-cavities, and around 35cm depth of glass-fibre-blanket loft insulation (albeit poorly fitted with lots of gaps between rolls and an area in the centre with no extra blanket at all, apparently to leave the existing boarded area free for storage).  The windows are all double glazed (more on them later).  So it should be nice and warm and efficient to heat, then?

Nope.

In winter it gets cold very quickly once the heating goes off (ie: the heat escapes quickly through the walls, window, roof and the cold uninsulated floors).  In summer it gets very hot when the sun is on the building.  According to our latest gas bill (we have no gas cooker so our gas use is only for heating and hot water) our average daily usage for the last 3 months is 38kwh.  According to Which that's about average for non-condensing boilers, equalling a yearly bill of £760 in our case.  That will increase as it gets colder though.  It's been unusually warm lately; we used much more gas this time last year when it was so much colder.

Planning permission progress report

Yesterday we got official confirmation that our planning application has been received and registered.  The full details (all 20 documents of application 1/D/11/001941...) are now available for viewing and comment on the council's website (apart from brief down-time for maintenance this weekend).  So it's passed the bureaucratic hurdle of validation, has been allocated a case officer, and things are moving along.  The planning officer allocated to the case should be making a site visit shortly (I still don't know whether or not we show them around or whether they just go and have a look from the street). The application is open for comments until 23rd December, so with luck we should get a decision early in the new year (they say we should hear by 12th January 2012).  Keeping fingers crossed.

Are free solar panel offers any good?

There's nothing exciting to report about the bungalow plans; our planning application has been given a reference number by the district council but not yet allocated a case officer.  If we get any real news I'll report it here...

So here's a relevant if slightly tangential blog about the merits or otherwise of the increasing number of free solar panel offers - companies offering to install photovoltaic solar panels for free on your roof, in theory giving you the benefit of free electricity.  I keep coming across these and a few people have asked me about them.  Sparked by the latest request for comment (specifically about these people: A Shade Greener) I found myself giving a rambling answer and thought I'd try and edit it into more coherent form to post here.

The free solar companies finance the panels they fit by using the Feed-in-Tariff/FIT (for more about the FIT and planned changes to it please see here: Solar Rush; or for more general FIT info this site is useful - http://www.fitariffs.co.uk/FITs/).  The FIT is in two parts: payment for all electricity produced by your solar panels - even that which you use yourself, and a bonus payment for electricity you don't use that gets exported to the grid.

On top of that there should be a saving on your electricity bill when you use electricity from the panels rather than importing it from the grid.

My understanding is that the free panel companies install and own the panels and receive both parts of the FIT. You get any saving from using power generated on your roof.  This can be worthwhile but it depends on how you manage your electricity use.

Planning application is in!

Wahoo - planning application is officially submitted!  Before it gets looked at properly by the planning officers it needs to be validated - checked to see if we have submitted everything required in exactly the right format.  I have tried really hard to make sure we have done everything correctly, but I've found it hard to know in advance exactly what all the information specifications are.  I highly recommend anyone applying for planning permission to start filling in the forms online (at www.planningportal.gov.uk) ahead of time - partly because it's time consuming, and partly because other requirements are made apparent as you go.  For example, we need to cut down one non-native tree which has been planted far too close to the existing bungalow: it's not enough to just mark this on the plans with a note that it needs to be removed, you have to label it and any other affected trees T1, T2 etc, and list this reference and the reference number of the plan that shows it in the right box on the planning application forms...

Other information about the required format of plans is more straightforwardly available, to be fair.  It's just important to make sure you follow the guidelines strictly (it's hard to know how accurate they are but there are plenty of stories on the web of applications failing to be validated due to minor technicalities).

But anyway, it's in, fingers crossed/touch wood it'll be validated, then we wait to see what the planners think.  They said at my last meeting with them that they'd probably need to make a site visit, so I guess that's the next thing in line.

Solar Rush

Our plans for planning application are virtually complete and now only lack details of solar photovoltaic/electric (PV) panels, and solar thermal (hot-water) panels on the south-southwest facing rear roof.  We will definitely install solar thermal panels to provide around 60% of our annual hot-water needs.  This is easier to plan as the panels are a fairly standard size.  We hope to also install PV panels, but this depends on the amount that can fit on the roof and the potential output of the system balanced against the cost.  As the sizing of PV panels is much less standard and the calculation of output and which panels to use in what configuration around roof-windows is much more complex, we need this information from solar installers.  Two local firms have agreed to provide a quote including all the relevant information, enabling us to reach a decision and - if we decide to go ahead - to include accurate details of solar installation on our plans for planning permission.

Of bats and bureacracy, Part 2

Brief summary of Part 1: the bat man checked for bats and found bat poo indicative of one bat, but couldn't rule out the possibility of there being more bats hidden between the felt and the tiles of the roof.  He then wrote us a bat plan which received the necessary approval from the bat people at Dorset County Council, once we'd resolved a few glitches (they initially failed to read the plans properly).

The bat plan (Dorset Bat Mitigation Plan/DBMP) sets out an approach to roof works that will minimise any potential disruption to bats.  Although the plan describes "a bat roost of low conservation significance", we have to act as though there may be more bats roosting in the space between the roofing felt and the concrete roof-tiles, just in case.  Had we known earlier about the need for a Bat Survey we could have carried out emergence surveys - checking at dusk to see how many bats emerge from the roof - and based the Bat Plan on more specific information.  Sadly, it was already October by the time we knew a survey was needed and at this time of year the bats aren't active in that way.  I'm not sure what they are doing, but it isn't flying in and out of roof roosts.

Of bats and bureaucracy, part 1

The last week or so has been a flurry of fairly stressful activity.  I haven't felt so stressed about the project at any point so far.  Thankfully as a result we now have nearly everything in place to finally submit our planning application.  I hoped to have done that by now, and as I'll explain one of the reasons for the recent activity also makes it more urgent than ever to submit the plans as soon as possible.  Urgh.

I went to see the planning officer again with the virtually complete plans (previously I'd only shown them my own computer mock-ups of possible designs, rather than the actual accurate plans).  The planning officer didn't really have much to add this time, having already commented on the basic principles of the project (and broadly approved - see Elevated Greenery), but she did add that we'd need a Bat Survey before we could submit our application.  Despite my best efforts to find out what additional information we needed to accompany the application this annoyingly hadn't shown up in any lists on the Dorset For You website or the Planning Portal site.  The Dorset website is so convoluted that I can't guarantee it's not on there somewhere in the depths but certainly not anywhere obvious.  The Planning Portal ("the UK Government's online planning and building regulations resource") does have a lot of information, but when it comes to local information requirements it just says that pull-down lists will show what you need when actually submitting a planning application online.  That's not much use in advance.

Design and Access Statement?

Below is a draft Design and Access Statement (DAS) to accompany our planning application.  It now appears we may not be required to submit one as the regulations have changed since the guidance I've been using was issued.  If nothing else I hope it provides a pretty good summing up of our plans and the reasoning behind them.

The property is in an Area Of Outstanding Natural Beauty which used to require a DAS for householder applications, but now it's unclear.  I'm sure the planning officer I'm meeting tomorrow will be able to tell me.  In any case, our project is unusual compared to standard applications for building an extension so it may help to submit the DAS by way of explanation.  Any comments from anyone used to dealing with things very gratefully received!  I'm sure it's too long for starters, despite a fair bit of editing down.

No more pink

I'm feeling very fuzzy headed but pleased, having just finished extensive 'artists impression' of the bungalow design and its position in the street, mostly to show neighbours when we go to talk to them about our plans this week, but it might help planning application too (to illustrate the proper plans).  This is a north elevation image capture (without the front garden and street) from the 3D model.

After a gentle nudge in the right direction from Kuba (designer) we've decided to go with plain lime render for the exterior of the strawbale sections, and are hoping the planners go for it.  We think it looks a darn site better than any 'brick-coloured' pinkish paint.  The render we're likely to use is a lime render made up using crushed recycled glass instead of sand, which we like the look of.  Much less energy is needed to collect and crush glass bottles than to extract new sand for use in the render.

I'm taking the plans and my Sketchup file/image captures to see the planning officer on Friday, hopefully (touch wood, if they don't want us to change too much) it'll be the last face to face with them before actually submitting planning application soon.  Just a few details to sort now...

Colouring

We're finally nearly there with the plans for planning permission.  I think I had in mind that this stage of the planning would be the simplest, perhaps because the fee for planning permission drawings is much less than that for building regulation approval drawings and construction drawings, as befits the fact that so much more detail is required at the building regs stage.  But so many details have to be thought about now that affect the overall design: details about what heat source we're using for example, along with what kind of chimney or flue it requires, where we want it to be and whether it can use an existing chimney or needs a new one built.  Although this doesn't need to be shown on planning permission drawings (which are concerned primarily with the external appearance of the building, and overall layout) it has to be resolved now - otherwise we may find further down the line that we need to change the layout somewhere, which could affect the external appearance and so require a revision to our application.  In short, planning officers don't need to know how we're providing heating, but they need to know where chimneys will or won't project from the building...  Also, although full building regulations submission comes later (if planning permission is granted) it is essential to make sure planned layout and use of space will comply now, to avoid having to make costly changes to plans later on.

Musical Interlude

Our designer is starting the build of his own strawbale home this month, and I'm waiting for various people to get back to me with information about different materials or kit, and in between massage work I've been wearing my music hat for a bit.  So instead of going into details of how if you insulate a wall internally too well, you increase the chances of condensation (and mould, rot etc.) at the point where the insulation meets the wall (one of the infuriating potential problems I'm waiting for technical advice on - it would be so much easier if the planners would let us wrap the entire building in straw, but I do see their point) - here's a musical interlude.

These tracks (and more) are on Soundcloud (soundcloud.com/bicipital-groove), a wonderful website for sharing music and getting feedback, hearing other people's weird and wonderful music that you wouldn't otherwise get to hear, and collaborating with complete strangers on other land masses that you will probably never meet.  It's great. The first track is such a collaboration - my accompaniment to a vocal-only track posted by a lady from Boston called Tea Leigh, asking for people to do something with it.  The second is all mine, a bit of electric mandolinery.

Chopstix (Tea Leigh/Bicipital Groove) by Bicipital Groove

Tears Before Bedtime (updated) by Bicipital Groove

The wonderful world of wood-pulp

As explained previously (see The Importance of Fitting In) when we wrap our bungalow with strawbales the bedroom that projects forward of the main building will remain as brick outside, in order to visually tie the building with the other brick bungalows in the street and appease the planners (see Elevated Greenery).  This presents some problems.

We want the whole building to be very well insulated and maintain a comfortable temperature without central heating.  The cavity walls of the existing bungalow will be filled (with glass-fibre granules made from recycled glass) but this only gives a U-value of around 0.57.  To achieve a central-heating-free home, we need the external walls to have a U-value of around 0.15 or less (there's some explanation of U-values here).  The strawbale wrap will easily achieve this for most of the building.  But in order to retain the external brick wall of that bedroom some kind of internal insulation will be needed there.  This in turn, presents some problems.

Elevated Greenery

Had another meeting with the local planning officer last week.  We thought it was about time to check they were supportive of our plans in general, and wanted to ask specifically how they might feel about a green-roofed extension.

There was a bit of humming and hawing, with the uncertainty based on the fact that externally insulating the bungalow with straw would turn it into a rendered bungalow surrounded by rows of near-cloned brick bungalows.  But they understood and seemed impressed by the reasoning behind the project (to bring a cold and damp bungalow up to at least level 5 of the Code for Sustainable Homes, making it warm, dry, cosy and healthy using the most sustainable materials we can).  However, ultimately they appeared to be convinced that our compromise of leaving the projection at the front of the bungalow as brick and internally insulating that section was acceptable and enough to visually tie the building in to the rest of the street.  Internally insulating is not ideal as there is more potential for condensation problems where the insulation meets the cold-hard surface of the external wall in a way which is not an issue with breathable external insulation - more on this in the blog soon.

Future-proofing and car crashes

We've had a change of plan about the massage treatment room which outwardly may not be very exciting but it was something that had been increasingly niggling at me, starting to consume a disproportionate amount of nervous energy, and turning mild concerns into raging anxieties.  Possibly the most absurd of these escalated worries stemmed from the fact that my clients tend to be a touch spaced out after a massage, coupled by the fact that most would drive to appointments: would I indirectly be the cause of hideous car-crashes as floaty-headed clients headed out into the tiny rural lanes, their response times fatally compromised? Well, probably not.  As a massage-therapist friend pointed out "most of my massages are where they come to me and they have to drive. I haven't yet heard that anyone has had a crash!".  I think this was an example of other underlying and more sensible worries getting randomly focused on that one idea, preventing me from having to deal with the real issues.

Strawbale wrappaging

By way of showing that wrapping a building in straw really is a viable and sensible option, below are photos of the strawbale wrap completed by Jakub Wihan (Kuba) in the Czech Republic.  The external appearance of roof and window details is likely to be different in our project, but the Czech build gives a good idea of what's possible.  Many thanks to Kuba for use of his photos.

The building before renovation

Wrap nearing completion.  Some of the ties used to clamp the bales to the wall are visible, along with the edges of the new boxes to accomodate windows/doors (photo by Jindra Sláma)

Cobwebs and measuring headaches

The most taxing mission yet (mentally at least) has been gathering the measurements necessary to arrive at the above sketch of the main roof trusses.  It looks so simple now it's done, but gave me major headaches as every time I tried to draw it in Sketchup major bits refused to meet where they should.  Unsurprisingly the bulk of the problems were my fault, usually not notating my on-site sketches clearly enough, thinking I'd measured from one point when in fact I'd measured from another.  The same issue applied when translating the measurements on the computer, starting a distance guide from the wrong point etc.  After a few trips back and forth from the bungalow I got it sorted, and was able to email the crucial info to Kuba (our designer).  The purlins in the sketch (long chunky timbers running the length of the roof to support the rafters - barely visible on the skethch as they're end on) still don't sit quite where they should, but I blame that on the impossibility of using perfectly straight lines to represent a fifty-year-old timber structure.

A good pair of boots

It's been a week or so of structural fact-finding missions for me and the bungalow.  Lots of crawling about in the loft, lifting roof tiles, sticking my head into small spaces to see what's going on (or just hands and camera into the smaller holes), and digging down through clay.  Large hairy spiders and their face-clinging webs are featuring large, and no doubt will do so in increasing amounts from now on.

The foundations.  Featuring large quantities of concrete, splashed liberally around and up the sides of the orginal foundation trench...

The importance of fitting in

Before deciding to make an offer on the bungalow I went to talk to the local planning officer again.  We needed to know what the planners' reaction might be to a strawbale wrap and extension of the bungalow.  The short answer is "mixed".  Normally, within certain criteria to do with size and materials that match the existing structure, side or rear extensions are covered by "permitted development" rights.  As long as you meet the criteria you can go ahead and build once you have building control approval (to ensure the construction meets current standards).  As Bridport lies in an Area of Outstanding Natural Beauty (AONB) all side extensions here need planning permission, as do any that don't match existing building structure.

So straight away, our project quite rightly does require planning permission.  This is then more likely to be given if the plans still comply with the restrictions normally covering permitted development.  Our plans clearly won't...  The planning officer was extremely helpful and generally supportive, but of course he has to work within the guidelines and regulations governing planning and development.  He explained that the main problem we might have comes down to the visual change from a brick bungalow (in a street of brick bungalows) to a rendered one, as the strawbale walls will have to be rendered.  He said that just extending with straw, but leaving the main building as brick would probably be fine, but was hesitant about the wrapping of the whole building due to the conflict of this with the guidance that development should be in keeping with surrounding structures.

Fact backed rant

I think it might be time for a bit of explanation of why we want to wrap a perfectly good bungalow in straw.  Because - like so many buildings - it isn't actually perfectly good.  It is structurally sound and mostly weather proof, both of which are very good things, but it is also cold, very poorly insulated, would require huge amounts of energy to heat, and is massively prone to condensation-related damp problems.  By wrapping it and extending it with strawbales (along with associated works to insulate floor and roof, and careful attention to details of design and construction) we aim to produce a home that is super-insulated, so requiring very little energy to maintain comfort levels, and remaining pleasantly cool in summer.  When necessary in the coldest parts of winter top-up heat would come from a highly efficient and beautiful masonry stove  in a central position (more on these at some point in the future) from where heat can easily circulate throughout the home.

But why straw and not some more common kind of insulation material or construction technique?  I've covered this is general terms before, so this time here are some numbers to back it up.  The key figures here relate to the insulating capabilities of materials and to their embodied energy.  Embodied energy represents the amount of energy used to make a product, including extraction of raw materials, processing, transport, installation etc.  There are different means of calculating this ranging from "cradle to gate" - preferred by some manufactures at it gives the lowest figure as calculations stop at the point the product leaves the factory, to "cradle to grave" preferred by most environmentalists as it provides the most accurate estimate of the energy consumed in a material's entire lifespan.  Generally, the higher the embodied energy of a product the higher the associated carbon emission from it's production and use, though this could potentially vary depending on the processes and source of energy used.  Even when renewable energy is used it is still important to move towards low energy use throughout production though, in order to ensure sustainability of energy supply.

The Bungalow

So then, the bungalow.  It's a two bed brick built, cavity walled, bog-standard 60's bungalow, that has mostly been left alone apart from basic redecorating and the removal of one wall.  The back of the bungalow and the garden are south/south-west facing, on a gentle slope, so are near perfect for catching the sun.  A very skinny stray cat has taken up residence in the "sun room" (a rotten shed-like extension with windows) after apparently being left behind by some people who moved away from across the street.  It's very friendly, which is nice, but clearly pretty ill too.  If it's still alive by the time we move in (we give it food and water when we're up at the bungalow by way of helping that happen) it's unlikely it and our small yappy type dog will get along well, but they just have to cope with that.  It's home will be disappearing at some point in any works too, but we'll cut it a hole in the shed so it can hang-out there instead.

The plan is to super-insulate the existing bungalow by externally wrapping it in new strawbale walls which will sit tight against the outside walls, and build a strawbale extension.  The image above is a guestimate of how it might look.  My 3D design skills didn't exist before I started trying to design possible layouts so there are lots of errors in the model, and it's liable for wholesale change once our strawbale building designer gets going on it shortly (http://jakubwihan.com/) - but it gives a rough idea.  I'll explain next time why the front bedroom that extends forward of the main building is left as brick.

Progress report (there has been progress...)

Apparently my last post was 10 months ago. There wasn't much to report over the winter as housing and land markets had their winter dip, then I just got a bit down and frustrated about the whole thing and didn't feel like writing the blog. Then suddenly quite a lot started happening and I thought about writing but haven't got around to it until now. I will try and update much more regularly now, at least once a month but more often when there is more to say.

As quite a lot has happened I'm not sure where to begin today. We have now bought an old bungalow to give a strawbale upgrade. I've been busy researching lots of things in relation to this, learning to use Google's Sketchup program (free 3D design software), drafting rough design possibilities for the bungalow, digging exploratory holes in the garden and more. That's easily a whole blog post in itself, so I'll return to it in more detail shortly. In the meantime, some kind of general update is probably in order.

As I said in the last blog, we decided to separate home and treatment room from pottery workshop and kiln, allowing us to live nearer the centre of town than we would be able to with kiln, workshop and home all together. The hope was that it would also make it easier to find suitable sites where planning permission was possible, and impact of any new build would be low.