August Arch Tests

Dog House Arch Form
In the photo above my son Will is washing bricks we’ll use to build a masonry arch on the front door of a dog house. A fancy dog house it is with insulated concrete walls, a barrel vault, masonry arch and a bottle wall in the back.

This past month or so we’ve been doing a lot of experimenting. We completed the very complex aquarium wall that serves so many functions between the bedroom and the bathroom of our tiny cottage. While we waited the 28 days for the mortar and concrete to cure to full strength we have been working on learning techniques we will need for upcoming projects like arches, parging, counter top pours and building a concrete sink that looks like a combination of sandstone and marble.

The purpose in the project pictured above isn’t to build a dog house, that’s incidental. The real function is to test out a lot of techniques and figure out how we want to do things. The dog house is actually practice for:

• Parging walls
• Building a Bathtub
• Concrete On Insulation
• Lightweight Insulating Concrete
• Ceiling pour
• Concrete Pigment Mixing and Marbling
• Masonry Arches
• Bottle Walls
• Waterproofing
• Earthshelter Dirt Cover
• Floating
• Hand Smoothing
• Grinding
• Polishing
• Waxing
• Key Stones
• Encapsulation
• Embedding

The fact that we’ll get two heavy duty dog houses big enough for our big livestock guardian dogs is a bonus. I like to do this sort of double duty so that a learning project also serves some real life function. Thus we also have built concrete domes for animal shelters and have a beautiful, although unused, piglet hut that looks remarkably like our tiny cottage in basic design. Practice, practice, practice…

First Form Design
This is the first form we made for doing arch pours. It worked. It was two pieces of 2″ foam glued together to make the arches. The problem was it was very hard to remove. There is a better way as shown below with the blue form…

First Form in Place
To do our first arch test we simply did it against the north wall of the bedroom. This area will be under the bed in the end so mistakes won’t be visible. More over the arch will become the edge of the frame for the bed thus giving the test a purpose.

Test Arch 1 – Ugly
A bit on the ugly side – good thing it’s way back under the bed! We failed to pack the concrete densely enough. It’s very strong, but ugly. Subsequent arches were far better. Live and learn…

A Better Arch Form
This was my second design for an arch form. It worked far better. It is smoother and very easy to remove from the finished cured arch as well as being easier to get level. The blue section is 1/8″ thick plastic taken from around a 55 gallon drum. The rest is simply 2×4’s all screwed together. Screws also go through the blue plastic into the ends of the 2×4’s. The resulting form is stable and light weight.

Arches from the Blue Form
Note the hand sander for vibrating the forms, the first granite window sill in place, but not yet cemented, under the Marvin window in the bedroom and the Marvin window itself with it’s view. These arches also had two bottle tests and some embedding tests. Then we parged the columns. Getting the parge really sticky is a trick.

More details tomorrow…

Outdoors: 76°F/53°F Sunny
Farm House: 74°F/60°F
Tiny Cottage: 72°F/69°F Dog House Tests