Monday, March 28, 2016

Building a Masonry Prototype

Over the past few months I worked on assembly of a masonry prototype which uses a recently designed, patented and manufactured proprietary topological interlocking concrete block.  This block design was discussed in my previous blog entry.  I think it may be helpful to share some of the steps involved in building this prototype.  I have some pictures showing the progress in chronological order below.  This prototype is not quite completed yet.  I'm about to start finishing the inside.

I was fortunate to have a proposal funded by the National Science Foundation (NSF) "Topological interlocking manufactured concrete block."  I wrote this proposal at the beginning of this project (6/15) and received the award just as the masonry was finished (1/16).  My company Spherical Block LLC is working on engineering and marketing solutions for bringing this technology to market. And: This material is based upon work supported by the National Science Foundation under Grant No. 1547958.  Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author, and do not necessarily reflect the views of the National Science Foundation.

First, I had a trench excavated for the foundation (my friend Martin Eddy was the man who ran equipment).  All trenches are at least 4 feet below the surface of the ground, to get below the frost line.

I used a concrete block system which is laid in the excavated trench, and each course is laid with two pieces of 1 inch rebar, both horizontally and vertically.  These block are simply 'dry-stacked' without mortar, and then the hollow cores are poured with concrete, to create a steel reinforced concrete foundation.  This was fairly quick and easy to do.

Here's my dog Bartleby wondering what I'm doing, and why.  Why?

Here's the plumbing being placed, to be cast in the concrete floor.

Here are the poured cores of the foundation wall.

I placed expanded polystyrene insulating panels on the floor, and ran plastic "pex" tubing for radiant heating of the floor.  This small test building has 3 loops of thermal pipe for radiant heating.

The floor was poured with concrete from a truck.  I used superplasticier to keep a low water-to-cement ratio (w/c) which makes better concrete.

My friend Chaz Curtis and his two sons, Tanner and Max helped place the concrete for the floor.

This is where the heating loops for the floor come out of the concrete.  A water heater will be installed to heat the floor, and the whole structure. Radiant heating will take advantage of the thermal mass benefits of this concrete test structure.

The dome section was then insulated, covered and shingled.

The walls were erected with standard concrete masonry units and mortar.  There are ~900 block, it took me 5 days to do the whole job, working alone (mixing mortar, moving block & laying block).

I made a custom slab for the roof over the entryway, to accommodate a small dome.

I built two rooms with arches, one on either side of the entryway.  These arches use the new block described in my previous blog entry.  These block were used for both the main arch, and for the small "gothic" windows.  #3 rebar was used for support and strengthening.  I built a temporary scaffolding to stand on while I lay the block for the roof.  Assembly was fast and easy.

Once the masonry was finished, stand-offs were attached to the outside of the building, as spacers for insulation.  By insulating the outside, thermal mass benefits are maximized.  The roof was finished with tarpaper and shingles.

I'll post more pictures as the last details are done; windows, painting, etc.  Finishing the inside starts now.


  1. Nicely posted article. I like the boy helping you in placing concrete on the floor. This is a good article. You may also like to know about quarry dust used in construction projects in-replacement of sand.