In Which We Drop Some Cordwood Science

Our cordwood construction workshop on September 21 was quite a success. Matt’s promotional skills drew in seven intrepid participants who made the journey out to Nerdwood to try their hands at mortaring up a few logs. They were a great group of people; all already had done a fair amount of research on cordwood and all had very interesting and varied backgrounds. They asked a lot of intelligent questions and worked hard. I hope they had half as much fun participating as we had hosting.

We started out with Matt giving an introduction, and on to Greg giving a talk about the house and our progress so far.

Greg and his invisible hoagie.

And then on to a tour of the interior of the house and some discussion of the masonry heater and some of the other features.

Matt's invisible cupcake.

Greg gave a spiel about lime putty mortar and demonstrated mixing up a batch in the mixer.

Sand + lime putty = progress.

We were then all set for the main event: building some cordwood walls. Off to the garden shed. I gave a brief demonstration of getting a wall started, and everyone quickly got down to business.

The front of the shed.

Rockin' that front panel.

The back of the shed.

Matt likes what he sees.

As you can see, these folks were naturals. By the end of the session, we had three panels halfway done. I did a little pointing demo and we wrapped up the workshop. Greg and I are looking forward to seeing some of the new cordwood projects our workshoppers are planning!

This visitor to the workshop had to be sent on his way back to the woods. Someone identified him as a Copper-bellied Snake (Nerodia erythrogaster neglecta), but after a bit of research it turns out that he was in fact a Red-bellied Snake (Storeria occipitomaculata occipitomaculata).

Sorry to disturb you, Storeria occipitomaculata occipitomaculata.


We’ve spent the last three or four weeks cordwooding the rear wall of the shed. This is the first real log laying we’ve done on our own, and it’s allowed us to get our mortar mix right and work out the (ahem) kinks in our technique. Eventually we’ll get a mortar mixer, but we’ve been mixing by hand (well, by hoe) in a wheelbarrow, with the idea that we’ll get more “hands on” experience of what makes a good mortar mix. Also, it will be easier to cough up the cash for the mixer if we know what kind of back-breaking labor it’s saving us from.


The first thing we have to do is some log prep – the logs we’ve cut, split and stacked are sixteen inces long (easier to manage), but the logs going into the wall are eight inches, so we cut them in half (using a jig attached to the sawbuck) and clean them up a bit. Here are some eight-inchers:

A bunch of Stumpy Joes

Now, at last, we can mix up some mud and start:

Scientific log structure...

We keep laying logs in the mortar and glopping more mortar between and on top of them. After the first day, we’re off to a good start:

Well, it's a tall wall to the small

Cordwood wisdom says the top third of the wall takes as long as the first two-thirds, and this definitely seemed to be the case. But hey, wall!

It's really mesmerizing...

Mixed in with the log-ends are “bottle-ends,” two jars or bottles with the mouths taped together and laid up in the wall like a log. They let in a bit of light and color, and provide us with a visual history of our jar-food consumption.

We'll pour our jars in reservoirs

The bashful winter

Look at all the choice ones!

Like much of North America, winter seems very hesitant this year in the U.P. Usually by the end of December, we have had many feet of snow (I believe we average around 240-250 inches a year) and are merrily cross-country skiing along the miles of great trails up here. Aside from a foot or so in early December and a snow shower here and there, we’ve had nothing. Nada. Bubkes. Very annoying for skiing, but great for log prep.

Well, it looks as though winter has finally arrived. You know that saying “Too cold to snow?” Not here. We are on a peninsula surrounded by Lake Superior, so when the air is cold and dry it picks up more moisture from the lake and dumps it on us as lake-effect snow. Just last week the icy Canadian blasts came to town and it looks like the trails will be ready this weekend (the U.S. Nationals were held here a few weeks ago and they had to truck in snow!)

In the meantime, here’s how it goes:

Makes me feel Scottish...

I throw the eight-foot logs off the top of the pile. The neighbor’s dog, Grady, is very excited about critters living in the log pile, but by the time I hoist the logs off, they’re long gone.

Choppy, choppy

We set the log on our sawbuck/cutting table and peel the bark off (usually it’s mostly fallen off anyway). We “borrowed” the plans for this from Bruce Barna, who helped his daughter Nicole build a cordwood “dorm room” not too far from here. The chainsaw attaches to a hinged plate. All we do is slide the log down the table until it hits the stop, pivot the saw through the log, pull the saw back up and repeat until we’ve cut up the entire log. At this point there’s a pile of 16-inch logs on the ground.

Clare (and her hat) moving logs

We move the logs to the pile – first, we filled up the kiln, then the back of the shed, now we’re working on a pile near the sawbuck.

The shed in all its plywood-clad glory

We hope to cordwood the shed walls this summer as we’re putting up the house frame and roof. This way we can experiment with various mortar mixes and techniques. Plus, cordwood shed!

Did I mention logs?

It's better than bad, it's good

Okay, you can’t have a blog without “log.” One of the many useful features of our shed is the greenhouse/wood drying kiln in the front. As I mentioned previously, we have about 25 full cords of 8-foot long cedar logs that were soon to be pulped. In order to use them to build a cordwood home, they need to be de-barked, cut, split (some of them) and stacked for drying. This is our current task, one we will continue until there’s too much snow to get at the logs. De-barking is easy, since the logs are three years old – the bark is already falling off. Since we don’t have a splitter yet, we’re cutting and stacking them in the kiln, as well as under the shed’s overhanging roof.

The Logs of Tomorrow

We’re not exactly lumberjacks, so after three or four hours of log wrangling, chainsawing and stacking, we’re done for the day, and beat, too. If we can cut 4-5 cords this season, we’ll be happy. Some of the logs have a bit of dry rot, especially in the center (very common in northern white cedar), which will have to be removed before we lay the logs up in the walls. Fortunately, quite a few of them are, as we say in the 12-sided solar cordwood house building scene, real choice ones.