Repairs to Hempcrete

These pictures below show a hole that was created on a very windy night when the tarp we were using to protect the new hempcrete from the 'elements' was in fact the cause of the only damage. It wasn't the first lesson we learnt but it was quite an important one. We never bothered with tarps after that. I think tarps may be more important in extremely wet climates. Our concerns with exposed hemp have tended to be more towards the hemp drying too quickly. 

Back to the holes....Firstly I damped down the hole using the mister on the hose. I then held a piece of formwork over the hole and shoved the hempcrete down behind it, filling the hole up. It was rather rudimentary but it seems to have done the trick. It's certainly one of the things that I really like about hempcrete, it is quite forgiving. I am also hoping that the rendering will hide many of these small imperfections. 

A rather large hole caused by a tarp hitting the
wall all night by strong winds

The hempcrete wall filled.

Aww cute, it looks a little like a love heart

The repair 2 weeks later, I am very pleased with the result.

Gable Ends - one down three to go

There was a great feeling of satisfaction building out the first gable. Seeing a wall completed to the highest point after so many weekends spent forming, mixing and placing, it feels like we are over a hump. The gable ends are being built out on the east end of the building. We have left the western end open so that we can access the attic for filling the ceiling in with hemp.

The gable ends don't need to be 300mm thick. They are really only there for weatherproofing and to provide a continuous external wall for rendering. We thought about sheeting the gable and rendering, but we had enough hemp to build them, so we opted for a 150mm thick hemp wall instead. This should also eliminate any risk of a crack that could occur at the joint between sheets and the hemp wall.

The main technical challenge was to set up formwork that could be removed. Attaching direct to the outside of the frame would lock the formwork in. Dad and I cut 6mm OSB sheets to fill in the frame spaces and attached them to the spacer blocks for the battens. The battens were installed to embed in the hemp since the frame would not be embedded in the thinner wall.

Closeup of the formwork for inside the gables. They weren't too neat, but good enough for a wall you can't see!!

The gable wall is only 150mm thick. It sits in front of the frame and won't envelop it. So the battens will be embedded in the hemp to secure it.

The 90 x 45 blocks served to space the battens from the frame. They also allowed for attachment of the OSB sheets for the internal formwork.

The lintel over the bifold doors. Battens with a bevel cut top and
bottom are fixed to the face to retain the hemp.

The conduit for our outside light over the eastern deck.

The rope and pulley on the right are used to haul the hemp buckets up the scaffold.

The renovation will be finished by Christmas

Everyone wants to know when we think we will finish the renovation. We just don't have any idea as there are a number of factors at play, our standard answer is now Christmas...although we aren't sure which Christmas.

However we are working hard over the Easter break (who said break!) and we are up to some of the very tricky bits to hemp. Mainly above the highlight windows and then onto areas such as below. I hope to have another blog entry next week with some more progress shots, fingers crossed.

An old photo from a few months ago, however I wanted to show
the area above the windows and high up towards the roofline
that still needs to be hemped.

Grant preparing the timber to place above the sliding door near the
kitchen and bifold door near the dining space.

The angled timber will be placed on the boards to help support the
hemp and anchor it to the wall where it doesn't envelop the frame. 

Note how the timber has been cut to provide a hemp anchor.

Sam working hard today.

The set up of our scaffolding, tamping and hemping tools ready to go.

The parapet

Hemping around the parapet, near the link to the old part of the house.

That's me looking rather fetching if I say so myself, particularly like the
sombrero and knee pad combination.

Grant amongst the rafters hemping above the highlight window, not
the easiest of tasks, Sam also got to do some of this tricky stuff. Don't
worry Alan, we have left some for you! I, on the other hand was a bit
too scared to climb up to the very top of the scaffolding.

Brewery progress!

Well we have had a busy month, Grant took a week off during March. Grant's dad was also able to come over to help for a number of days, I hope you are enjoying retirement Alan!! The plan was to get the hemp walls built around the brewery/workshop...who am I kidding, it's a brewery! The first couple of metres worked very well. Grant and Alan set up the formwork so the entire perimeter could be completed in one go. It's much easier than doing a wall at a time and having to grade out at the end of the formwork. Sometimes we have been so keen to get the pan mixer going, but really it is much better to have more formwork set-up before starting. Of course, more formwork equals more cost, but we have managed to pick up some used concreting formwork and kept the costs in check.

Section of the brewery

Julian and some of the other builders putting battens along the ceiling
in preparation for the MgO board

A bit of the step that runs from the link to the renovation. When the concrete
was poured the plastic made this large crease.
Nick has ground it back and will grout the last bit before it is polished.

Battens in place, we just need to make room and order the MgO board.

Hemping around these pillars has not been easy so we are hoping our
novel method of adding fast wheels to help the hemp adhere to the
pillar works. Time will tell.

Julian and Paul adding the battens

Nick discussing the door jamb with Grant!

Beer and building make for a happy pair. We reused the beer wort
container (we have been buying wort as we are too busy building to
brew a full mash)

Grant managed to make a large scoop out of the container. This is to
help us get to the tricky parts of the wall, such as when the wall
meets ceiling.

Progress for February

Once again we have only managed to work on the house over the weekend and the odd day here and there. We now have hemp surrounding the entire renovation up to to at least 2.4m - it is a milestone. We are getting close to the stage of using the hempcrete as ceiling insulation. We will be lining the ceiling with MgO boards (a board that looks like plasterboard but is breathable) then dumping a mix of lime, hemp and water (no sand this time). This will then join up with our hemp walls so that our ceiling and walls will be completely cocooned.

looking towards the front of the house

this area above the highlight windows was particularly tricky to hemp
with big beams and a small gap between the formwork and roof. It could be worse.
There would be less gap with a skillion roof.

you can see where the hemp has been finished to, right where the black
bituminous paint is, the hemping will continue all the way along

The west side of the link, the hemp is finished within the old part of the
house, in fact the hempcrete is filled right up against the old back door.

We do have 3 tonnes of lime in one of the sheds but as you can
see we are down to 4 pallets of lime still sitting on the extension floor.

this was our lime

Looking into the window from the north, eventually there will be some
decking here.

Filling holes and Fast wheels

Matilda has been filling these conduits with hempcrete left over from the end of the day.

She hands them to me and I insert them into the holes and use a piece of bamboo to push the hempcrete into the wall. It is a job that needs to be done yet we are able to complete it in a relaxed way, when we have both the time and the leftover hempcrete.

The fast wheels are used to provide something more substantial for the hempcrete to hold on to when we have only 50mm deep hempcrete. We are experimenting with this and some of the wheels have had some OSB added to make it easier to pack hempcrete behind the fast wheel.

Pushing in the hempcrete using the bamboo.

the completed western wall with holes filled

This is a filled in hole,  I have tried to make it either flush or a little
under so that it will be easier for the renderer to achieve a flat surface

We have added a little piece of OSB when we screw in the fast wheels to give it some depth.
Hopefully by doing this we will give the hempcrete something firmer to hold on to when there
is only 50mm of hempcrete.

The fast wheels get covered up with the hempcrete. Note we have also
painted the nail with bituminous paint.