After that surprise dinner at the Chef’s Table we were back in the dog house again. Or rather working on the dog house. Admittedly this is rather fancy, and very solid, for a dog house. The reason we’re going to all this trouble is to explore ideas and techniques before applying them to our tiny cottage. In fact, the dog house is very much a miniature version of our home to be.
Once the base of the dog house was well cured my first step for today day was to build the arch form. We used a reuseable arch form we had made a few weeks ago. We have already poured several other arches using this form but this would be the first time I used it for laying brick. The style of arch we’ve chosen is called a Roman arch which is also known as a semi-circlular arch or rounded arch. It is sized to the inner doorways and partition arches of our tiny cottage. This makes it so our practices sessions are more meaningful. When we go to do the real thing we’ll have already worked with this shape and size many times. After my fifth arch I feel like I’m finally getting the hang of it. Not perfect, but closing in on it and way past the 90% mark.
This is the first masonry arch I’ve done. To get the spacing of the bricks right I cheated. I used a 1/8″ diameter wooden stick to hold the bricks apart while I tapped them down. This made a fine jig. At first I also had tried doing that on the outside of the curve as well but I found it was not necessary. Better for me to observe the flatness of the brick to the curve and use that to get the angle right. I had considered setting a board behind the arch to push the bricks against to get them all in the same plane but found that wasn’t necessary.
While I worked on the masonry arch Holly and Will parged the exterior of the foam walls of the dog house. This is a test of building a bathtub as well as parging interior and exterior walls of our house. One trick is to score the foam up a little bit before beginning to parge in order to give it a rougher surface so the concrete sticks. They are using the same mortar mix as I am for the bricks. The formula in parts by volume is: 1.5 water with dish soap, Calcium Nitrate accelerant & Aquron 300, 3 portland cement, 1 lime, 6 sand (3/8″), 1 small handful PVA fibers.
A mistake we made is that we should have finished the pillars below the arch before doing the arch. It worked, but the arch was balanced on just the pink foam. Doing the doorway pillars first would have been easier and safer. Live and learn – one hopes.
I had planned to cut a keystone out of waste granite that we get from the local quarries and stone sheds. As I looked through my pieces of granite I saw a perfect natural stone – it fit exactly. Dang! I couldn’t use it because now I would have to save it for the real arches inside the house. On further investigation we found a dozen similar naturally shaped key stones within a short distance of the work area. Thus the arch has a natural rather than a cut keystone as planned – serendipity strikes again!
After we were all done with the arch and it had hardened a bit we washed the bricks to remove concrete stains. This is important to do as early as possible to avoid the stains setting as the concrete cures. That meant removing the form to get the last bit of brick work clean on the under side of the arch and being very gentle. The arch looks great!
Outdoors: 65°F/51°F Sunny
Farm House: 73°/59°F First day house exceeds outdoors – fall is coming
Tiny Cottage: 74°F/68°F