Mud-dauber Wasp demonstrates superiority

I've had a weekend off, but in my absence a tiny little Mud-dauber Wasp appropriated a small corner of the little red window to create an entire purpose-built adobe home for its family, installed the future family in it and stocked the larder with * horror alert * tiny little live paralysed spiders.  Isn't nature grand?

The workwomanship is simply exquisite.  You can just see in the photo the different mud colours.  The wasp has identified that the lighter colour mud from Hepburn is better for building, then it has used our own terra-cotta coloured earth to make it pretty, or camouflage it, or whatever.  It's altogether slightly Attenborough, yes?

The final straw

Gratuitous picture of Trevor

A few hours ago, I placed the final piece of straw in the final light-earth wall.  The structure of the building is done. 

Actually, it was a great way to finish off - I tried out a whole new technique for a different type of wall that we will probably use next time.  More on that later.

Last weekend, TJ put the roof on the bump-out.  That's him on the roof looking groovy with his new hammer drill (a Metabo, replacing the Makita that burned out twice - the Makita fought the shed and the shed won).

This weekend we mudded the last external wall, which was the triangular gable above the window-seat roof.

North wall core completed

The last bit of light earth on the exterior of the building was the gap between the frame and the roof above the new gable panel, to keep critters out of the roof cavity.  I had to get up on the window-seat roof and lie down to get my head and arms underneath the main roof's overhang.  Intensely uncomfortable. 

Gable - done and critter-proofed

You'll notice we buried the raw edge of the window-seat roof in the gable wall.  This is the sort of easy finishing detail you can do with mud but nothing else. It will never, ever leak.

Then we made an interior wall next to where the wood fire will go.

This final wall was an experiment to see if we could make a really solid thin wall, because I think the foot-thick walls on this building slowed us down a bit. If we do this again (TJ needs a woodwork shed) we'll do thinner walls.

The main challenge was to find a way to make the light earth stick firmly to a single stud, instead of having a double-stud "larsens truss" with a cavity in the middle to hold the wall.  After all these months of using bamboo to solve problems, the solution was obvious - TJ drilled holes in the frame and slotted in lengths of bamboo that spanned between solid wood, so when they are buried in a rigid wall they will be completely immoveable. I think in a stud wall for a new building, the bamboo would be horizontal, like a noggin, between vertical studs.

Single stud frame, cement sheeting and bamboo in place

The frame was backed with cement sheeting, to protect from the wood fire.  

Making and positioning the light earth took most of the day, but we completed 3.5m2  - more than double the area we could have built of foot-thick walls.   Don't get me wrong, I adore the thick walls and the curved lintels.  But thinner walls take less than half the time, which is not to be sneezed at - it might have knocked 6 months or more off this project.

Light earth, piggy-back formwork, wall-top technique

The photo above actually shows the last bit of straw we will use in the building.  We ran out of straw at that point and had to scrounge around for fibre to finish the wall.  But it's a good spot to look at the building method, and what we've learned.

Formwork made from scrounged MDF, but reinforced with pine boards.  The pine is offset so one board slots into the one below. In the gap above the top formwork (not usually as big as this, but meh) use a thin metal object like a float, or in this case a plasterer's hawk, and shove the mix in from the side.

And that's it.  The last wall in place.  When I walked outside I looked at the building and it struck me that I've lifted tonnes of mud and straw into place, bit by bit.  And I've grown some muscles, let me tell you.

New wall.  Now it's just fit-out, floor and render

Weekend alone smearing muck onto the walls

On yer marks

I spent last weekend alone and did the thick "parging coat" (undercoat) of render on two wall panels.

I made the job harder for myself by making a really weak, watery render mix on Saturday, which I tried to thicken by adding more fibre.  It was so hard to make that useless muck stick to the walls, I had to abandon my tools and smear it on with bare hands.

Render this - you just need to make mud defy gravity

I made one bucket of stickier render, which I rationed to use on the window surround.  Even then, it threatened to glop off onto the floor every couple of minutes.  I had to keep pushing it in place until it started drying.

Juuuust holding on

Still, I worked at it alone and got the wall finished.  There was a certain amount of "I am woman, hear me roar" going on.

You can almost see how fibrous and nasty the render is from here

Next day, I mixed some render that was extravagant with clay and sloppy as a cow pat. It practically lifted itself onto the wall.

Ta da!

It was peaceful working out there, alone in the bush.  Fresh air, bird-song and fresh food from the garden.  And there's nothing like staring into the corner of a building for two days to make you appreciate the view.

How's the serenity?

Ceilings ... nothing more than ceilings ....

Window seat becomes cosier

Last weekend we put a ceiling on the window seat bump-out, insulated it and finished the walls up to ceiling height. Suddenly the space has a greater feeling of depth and enclosure.

TJ puts up the ceiling boards, blocking out the sky

TJ got some old pine floor boards from a recycled timber yard, cleaned them up a little and put them in place.  That sentence accounts for two days' work!  

When we framed the bump-out we were very careful about the frame being vertical, but less so about it being square.  So there was a certain amount of adjusting and cutting to make the ceiling fit.  Welcome to amateur-land.

We considered at least half a dozen ceiling insulation options.  The main problem was that it's only a small area so there would be heaps of waste using a commercial insulation product.  Then we considered unofficial stuff like loose wool and blankets, until the idea came.

Light Earth insulation

Tucking Light Earth insulation into the ceiling was one of the quickest mud building jobs we've done.  For once, gravity was on our side!  While we were at it, we filled the top of the wall between the windows and the ceiling, so the area is completely enclosed.

TJ adds battens for the tin roof

We've left the insulation to dry under a temporary roof.  We should be able to complete it next weekend.  The other thing we hope to finish next weekend is the gable above the window seat - the last external wall of the mud shed.

Looking in the west wall window

I loves those niches to pieces

Window seat area with windows old and new and a niche - it's shaping up well, yes?

Working on the very shapely north wall and window seat means that every one of those little details that we've been planning for months or even years comes to life.

The latest bit of fun is the niches.  We planned two - one with shelves and one with just a ledge at the bottom.  The challenge was to create some niche-shaped formwork that could sit there while I made a wall around it, then removed later.  I'm not the world's greatest carpenter, so I sweated and worried and procrastinated.  Eventually, I did what comes naturally - improvised!

Wheely good formwork for niche with ledge

The wheelbarrow wheel exploded that day when all the infrastructure failed.  It turned out to be just the size and width I needed for the curved top.

On the last day of our summer holidays we mudded the first niche into place.  That day was a real slog and it was sad letting go of the summer hols, so pulling out the wheel at the end of the day and revealing the niche was a bit special.

Freshly minted niche - still wet, with bamboo in place

I buried lots of bamboo in the wall to hold the curve and support the structure.  I also used three or four strong pieces of bamboo as a lintel buried horizontally above the niche, to spread the weight of the full-thickness wall above the niche to the columns on either side.  But once the wall is dry and set, it takes its own weight nicely, so I snipped out some of the bamboo.

Partly dry, with some bamboo removed

The rest of the bamboo will stay buried in the wall and I'll render over it.  The key-hole shape is accidental, but I kind of like it.  Later on I'll decide whether to snip out a bit of straw to make the walls straight, or leave it like that.

Last weekend we finished the last full-height wall of the building (whoo!), which contains a matching niche with three shelves.

Wet wall: niche with three shelves all wrapped up, ready for the big reveal

The shelves are meant to look like they are just sitting in mud, but really they are attached to a strong framework buried in the wall.  The photo at the top of this page shows the niche in the wall, and the context.

It is soooo hot here.  I'm writing this in the shade, waiting out the heat of the day so we can work again in the evening.  Hopefully it will drop below 30oC because we are putting a ceiling on the window seat area and it is very exposed work.  

North wall! Finally! Whoo!

Still life of new wall in setting sun

Yesterday the north wall finally starting taking on some bulk and shape (not to mention a window in a frame - booyah).  

That's the thing about Light Earth; once the details of ordinary building are completed and some dodgy formwork made, the walls grow quickly.  More quickly yesterday, because above waist-height, most walls are only 10cm wide, instead of 25cm.  

It was very interesting watching the inside of the building change in character as it became enclosed.  

The most notable change is the acoustic, which is shaping up to be extraordinary - quiet and clean, but what my old musician buddies call "live".  

There's more done, but we ran out of light and decided to leave some of the formwork on overnight.  And speaking of formwork, it's time for the January 2012 Dodgy Formwork awards!

Dodgy formwork winner

I don't think it's possible for formwork to get any dodgier.  But it did the job. My personal faves are the bit on the corner held on with a clamp, and the bit with the wavy edge.  Why wavy?  It was cut for the shape of the rocks below the window, and we are re-using it here.

Creative special mention

 Why is there a wheelbarrow wheel in the wall cavity?  Watch this space.

Honourable mention for being odd but kinda neat

Patience

Still horizontal and not affixed to any wall

Patience. It's a virtue, apparently.

Two people, three hours and the big northern window is still lazing around on the saw-horses.

Clearly, carpentry is not my forte.  Estimating the amount of time it takes to do carpentry is even less of a forte.  Here's me thinking we'd pick up the replacement glass, pop the window in the wall and get on with some lovely mudding. I mean, we had a huge wooden rectangle frame and two as-yet-unbroken bits of glass.  Join frame A with glass B and get on with it, yes?

The thing is, apparently you need strips of wood around the edge of the window, nailed to the frame to sandwich the glass into the rebate.

This is what three hours looks like

Most people just buy these strips - they're called quad.  But apart from destroying native forest, new hardwood quad would look stupid against the gnarled old second-hand wood of the frame, so we cut these strips from more gnarled old planks.

Then there was measuring, sawing, planing, sanding, oiling, measuring again, sawing again, little beads of silicone, tiny little nails (swinging a hammer less than 1cm from glass!). We're nearly there, but I said that the day before yesterday.

On the bright side, we haven't broken any glass lately.