Friday, December 2, 2011

Masonry and wood


Corrado “Junior” Soprano:   “My father was a master stone mason.  He never cut fucking wood.”

-          From HBO’s “The Sopranos:  He is Risen”

Masons are known to sometimes be contemptuous of wood as a material, and of carpenters and carpentry in general.  Yet wood often plays a critical role in masonry construction.

Wood is tough.  In engineering terms, this means it is less prone to crack propagation.  Wood is also much less dense than stone or concrete.  It is also a good thermal insulator. 

Wood is sometimes used in a masonry type of construction, known as cordwood construction, stackwood construction, or stackwall construction.  Cordwood consists of logs that have been cut into lengths which are suitable for burning in a fireplace or woodstove, around 16 inches to around 24 inches in length (~40 cm to 60 cm).  This wood can be split or left in the round.  The length of the logs is the thickness of a wall to be built.  Nice thick walls: very strong and good insulators.


To build a cord wood wall, the logs are simply stacked as one would stack firewood.  A layer of mortar is placed between logs, much in the way mortar is placed in beds between rows of stone, block or brick.  The only real difference is that the mortar is typically half mortar and half sawdust.  This makes the mortar a better insulator, and much less expensive.  Sawdust in large quantities can usually be obtained from your local saw mill, either for free or very inexpensively.  It is simply added to dry mortar, dry mixed, and then further mixed after water is added.  For greater strength, holes can be drilled through the logs and they can be spiked together, as is being done in the picture below.


I am currently building a combination log cabin/cord wood building.  I’ll be using it to contain a sauna, with a bedroom upstairs.  The upstairs walls are all cord wood construction.  Some people like to include glass bottles in their walls to allow light to pass through.  I used a bunch of handblown glass spheres in my walls.


I must warn the reader that if he or she ever decides to do this, one must be very careful with the chainsaw.  I almost cut my left foot off last week.  I’m sitting here typing now with a big cast on my foot; I’m very lucky I didn’t lose my foot!  I just got back from a week in the hospital.  I had to be flown out on a helicopter.  Please be cautious.  I was working alone.  I knew better, but was racing the onset of winter.  If I were a master stone mason, I would never cut fucking wood, and I would never cut my fucking left foot.  Foolish me.

I apologize for cursing on this entry to those who may be offended, but it really hurt.

Here is a picture of the finished sauna building:
 

5 comments:

  1. Sorry to hear about your foot. One of the best and most important a person can do about an accident is to admit the error and advise safer measures. We would never want this to happen to anyone and emphasis on safety usually bores people so a poignant story keeps one's attention.

    I am very envious of the building you are constructing. I would love to see more pictures, some with the light percolating through the glass.

    I heard this about stacking cordwood, loose enough for a squirrel to get through, but not a cat.

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  2. Here are some pictures of the sauna being built. I had help with the first 4 logs, the rest was done by myself, working alone (with a chainfall: a sort of hoist).


    https://www.facebook.com/media/set/?set=a.2357213686552.131853.1136529319&type=1&l=94e6d0b1c1

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  3. What a nice post! Thank you for sharing this interesting and informative blog. Masonry should not just be about bricks and blocks but most especially precision, quality and affordability. If you want to construct unique stone, brick or concrete architecture to adorn your home, while remaining within budget; then contact Mento today. Masonry Needham

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  4. Can this method be used for floor construction?

    I have the opportunity to use young teak logs to small to mill for a covered patio floor using cordwood construction methods.

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    1. This would be challenging. This is like a parquet flooring, with the end grain at the 'top' or vertically oriented. I would not use mortar between wood, as is done in the walls. You'll want a tight fit between pieces of wood. Here's a link for a video showing it done, this person cut their wood into hexagons, and tiled it together like a 'honeycomb." Teak is a very hard wood, so it should stand up to wear fairly well; that's the good news. Good luck! https://www.youtube.com/watch?v=PgmingPJObk

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