building
practicing the fine art of slaking quicklime in an old bath tub.
July 7th... A few days ago Ben Scott (pictured with me above) came by and taught me how to slake quicklime. This was a very eye-opening event for me - not so much because of the actual process as the realisation that I might be biting off way more than I want to chew!
My original estimate of the amount of quicklime I would need for the job was six tonnes. During our little practice session we did 20 kgs. It took about half an hour. At that rate six tonnes would take me about 150 hours. Add to that the process of sifting the lime putty to remove impurities - another 30 minutes - and it starts to look completely impractical!
However, I did realise that my original calculation of quantity was probably excessive since the quicklime actually produces at least double its volume of putty, rather than the one-and-a-half times I had thought. So perhaps I can get away with four tonnes... but that is still a huge amount of slaking and sifting.
So, I need to go back to the drawing board. What I am now considering is to use a number of different forms of lime throughout the building. Maybe hydrated Type S for the interior walls, pre-hydrated pure lime mixed with pozzolans for my scratch and brown exterior coats; and then use the slaked quicklime for the top coats. This will also allow me to gain experience with several types of lime.
July 9th... Yeah!! we got the variance! One more step in the process completed, and we can start working towards getting our building permit.
The Board of Variance meeting took place last night and it turned out to be a very brief and easy process for us. The five members were very complimentary about our application, asked if we had anything we wanted to add, agreed that they had no questions they wanted to ask us, and that was it! We were in and out in a couple of minutes...
This coming Tuesday (July 14th) I have my first 'serious' meeting with my engineer - David Romain - to start work on the techical process of taking my ideas and turning them into plans that he can 'approve' and which can be submitted to the planning department!
July 14th... Two steps forward and one step back... I thought I had figured out what I was going to do with my plaster: lime, in various forms, for all three layers. But recent research has now presented another option that needs serious consideration: using an earthen (clay) plaster on the bales, with a final coat of lime for protection.
I still have a lot more research to do but it seems that, while there are some challenges with this system, the advantages of using an earthen plaster may be considerable. One of the first things I need to do is get the earth at my building site tested to see whether it will be suitable. If it is, then I could be saving a lot of money with free material and no transportation! I will add more information as it becomes available!
For the moment I am continuing to slake a reduced amount of quicklime (about half a tonne) for my finish coat. This Sunday (july 19th) I intend to hold a free demonstration for people who might be interested in the process. (see the Events page).
July 15th... Yesterday afternoon I met with my structural engineer.
We started by discussing his fees and his estimate of what it might cost for his services. Happily I didn't get 'sticker-shock'. He indicated that it usually costs about $1.25 to $1.50 per square foot on average, and then a charge for each site visit at a rate of $165 per hour.
Given that our project falls completely outside of the building code in so many ways, I anticipate that we will need extra visits, but my estimate is that his services will probably cost about $3000 - $4000. That will add about $3-4 per square foot to the final price.
After we had established the cost, we got down to the 'real' work and, starting at the bottom, focussed out attention on the foundation system. It was a very constructive discussion for me, reassuring me that, from an engineer's perspective, everything I am proposing is viable. I have updated my foundation diagram to reflect the latest design. This may (probably will) be modified once David gets his teeth into it! :)
David is very supportive of my plans and has a great optimism, believing that you can always find a way to do something if you have the will! He also had a very good suggestion that, as we work through the various elements of the building - foundations, floor, supporting structure, etc - we should present each element to the inspectors. His idea being that, if they have seen and discussed each of the components with us during the planning process, they will not be overwhelmed by a flood of alternate materials and methods when we finally present our plans for approval!
Now I have to get the soil sampled so that we can determine whether it is suitable for use in rammed earth...
My original estimate of the amount of quicklime I would need for the job was six tonnes. During our little practice session we did 20 kgs. It took about half an hour. At that rate six tonnes would take me about 150 hours. Add to that the process of sifting the lime putty to remove impurities - another 30 minutes - and it starts to look completely impractical!
However, I did realise that my original calculation of quantity was probably excessive since the quicklime actually produces at least double its volume of putty, rather than the one-and-a-half times I had thought. So perhaps I can get away with four tonnes... but that is still a huge amount of slaking and sifting.
So, I need to go back to the drawing board. What I am now considering is to use a number of different forms of lime throughout the building. Maybe hydrated Type S for the interior walls, pre-hydrated pure lime mixed with pozzolans for my scratch and brown exterior coats; and then use the slaked quicklime for the top coats. This will also allow me to gain experience with several types of lime.
some of the tools I have made or adapted to help sieve the lime putty after slaking.
July 9th... Yeah!! we got the variance! One more step in the process completed, and we can start working towards getting our building permit.
The Board of Variance meeting took place last night and it turned out to be a very brief and easy process for us. The five members were very complimentary about our application, asked if we had anything we wanted to add, agreed that they had no questions they wanted to ask us, and that was it! We were in and out in a couple of minutes...
This coming Tuesday (July 14th) I have my first 'serious' meeting with my engineer - David Romain - to start work on the techical process of taking my ideas and turning them into plans that he can 'approve' and which can be submitted to the planning department!
July 14th... Two steps forward and one step back... I thought I had figured out what I was going to do with my plaster: lime, in various forms, for all three layers. But recent research has now presented another option that needs serious consideration: using an earthen (clay) plaster on the bales, with a final coat of lime for protection.
I still have a lot more research to do but it seems that, while there are some challenges with this system, the advantages of using an earthen plaster may be considerable. One of the first things I need to do is get the earth at my building site tested to see whether it will be suitable. If it is, then I could be saving a lot of money with free material and no transportation! I will add more information as it becomes available!
For the moment I am continuing to slake a reduced amount of quicklime (about half a tonne) for my finish coat. This Sunday (july 19th) I intend to hold a free demonstration for people who might be interested in the process. (see the Events page).
July 15th... Yesterday afternoon I met with my structural engineer.
We started by discussing his fees and his estimate of what it might cost for his services. Happily I didn't get 'sticker-shock'. He indicated that it usually costs about $1.25 to $1.50 per square foot on average, and then a charge for each site visit at a rate of $165 per hour.
Given that our project falls completely outside of the building code in so many ways, I anticipate that we will need extra visits, but my estimate is that his services will probably cost about $3000 - $4000. That will add about $3-4 per square foot to the final price.
After we had established the cost, we got down to the 'real' work and, starting at the bottom, focussed out attention on the foundation system. It was a very constructive discussion for me, reassuring me that, from an engineer's perspective, everything I am proposing is viable. I have updated my foundation diagram to reflect the latest design. This may (probably will) be modified once David gets his teeth into it! :)
David is very supportive of my plans and has a great optimism, believing that you can always find a way to do something if you have the will! He also had a very good suggestion that, as we work through the various elements of the building - foundations, floor, supporting structure, etc - we should present each element to the inspectors. His idea being that, if they have seen and discussed each of the components with us during the planning process, they will not be overwhelmed by a flood of alternate materials and methods when we finally present our plans for approval!
Now I have to get the soil sampled so that we can determine whether it is suitable for use in rammed earth...