Log cabin alternative

[nathan.principe]

I thought this was a pretty inventive idea I saw on another forum, thought I would share  http://www.small-cabin.com/forum/2_599_0.html

[John Raabe]

This is a very interesting solid wall system. While it would have many of the same problems standard log houses have (plumbing and wiring, meeting code insulation levels, etc), it does solve many others:
• Uses stable KD lumber with glued joints
• Flat interior walls for standard frame partitions.
• Lower material and transportation costs.
• Easier for owner-builders than log kits and more flexibility.



Here is a link to the authors $15 booklet on this system:
http://cgi.ebay.com/Lumber-Log-Structures-Easy-Cheap-Log-Construction-/120633677433?pt=LH_DefaultDomain_0&hash=item1c1653d679

[mtman]

 I bought one of his booklets. Haven't read it all yet, but it is well done and nice pics. Would make a nice cabin, or shop building.
I'm wondering about the insulation part for colder weather, would the 6'' of wood once warmed up inside hold heat well enough without insulation? I would hate to build one and cover the inside up as I like the looks of wood.

[Don_P]

R value is closer to R1 per inch, the "thermal mass" effect is not considered to come into play under 8" of log thickness. The glue needs to be structural, subfloor glue is subject to creep. This idea is not new, this is also not really the correct way to do it.

Here is one manufacturer, I know of others;
http://www.anthonyforest.com/powerlog.shtml

[John Raabe]

Thin solid wall houses do not often do well in cold climates. This lumber-log system could be fine for a utility structure but not all the details are worked out for heated and cooled residential structures or strict code compliance areas.

Yes, the author's statement of R-2 per inch of wood is hopeful at best. My dad's 1967 solid cedar walled cabin had problems in its mountain winter location and needed 1-1/2 inches of foam board insulation on the interior to get some control over heating costs. And then, of course, the interior never looked as nice since it was no longer a match to the exterior cedar (dad used rough sawn plywood - not a good choice..ouch!)

I've posted elsewhere about the problems of logs in full sized residential homes. Log still works best for what it was originally designed for: small rustic structures that are not expected to last a long time. This system is an interesting upgrade to that but it will not replaced frame wall construction.

[MountainDon]

If anyone wants to play around to see the theoretical performance of this wall system to conventional stick or whatever, the ResChek energy efficiency calculator has provision fpr solid wood walls, various species and thickness.

http://www.energycodes.gov/rescheck/

Since many jurisdictions (like mine) require the plans be run through ResChek when applying for a building permit. Once all the windows, doors, etc.  have been entered it's simple to change wall construction and insulation types to see differences.

[bayview]

   I am with Don_P on this one . . .

   I had seen a similar construction for a childs play house.   With the natural contraction and expansion, the play house was full of gaps and twisted lumber.   I think a home with the same construction would be cold and drafty.

/.

[nathan.principe]

All very valid points, this method wont be winning any energy star awards any time soon.  Looking past that, what really struck me about this is its completely off the shelf inexpensive materials, I believe a novice carpenter could be successful, and once the wall is done its done ( no exterior or interior sheathing, house wrap, insulation, etc).  This would make a very nice weekend get away or hunting cabin

[Don_P]

It is off the shelf. Inexpensive... not so sure. At 13 rows high x 3 plies that's 39 2x8's per wall section, and lots of glue. I would bet if you put pencil to paper you can stick frame the wall and apply 1x8 T&G inside and out...
An 8' long section of wall building these logs contains 416 board feet of lumber.

Stick framing that section takes 10 2x6's-80BF
Sheath it in 1x- 64 bf
1x8 T&G inside and out 128- bf
Total-272 bf

Log or full timber construction is not necessarily easier for the novice. Electrical? I bore holes from the floor to the device and often continue that hole to the roof for lights. I then mortise the boxes in. I've seen novices drill out through the sides of their walls, miss holes, box sizes, etc. The walls should be aligned at every connection and maintained plumb and straight. These thin ones need internal bracing to lock them in place. Can this be done? Sure. I think laminated logs have a whole lot of potential, but don't fool yourself.

This is one of our local producers. The fellow that started laminating for them is a doctor of glueology
http://www.turmanloghomes.com/turman-engineered-timbers.php

[MountainDon]

I've had a quick look at rough costs. Local prices on framing lumber, wrap, insulation, sheathing and 1x T&G boards inside and out has it looking like the "reassembled log" technique might save some money on just materials. However, I can't get my self too excited about the technique because of the electrical wiring, water supply plumbing and propane/natural gas lines difficulties that I foresee.

One other issue I wonder about is the amount of time it would require to assemble the "logs". Plus the glue. As Don_P pointed out ordinary construction adhesive may not be the best product to use. It seems to me that pretty much any alternative to stick construction always takes more time and effort to erect. Maybe that's just me.

As for the claim of "once the wall is done, it's done" I'm not sure. If it was me I see myself doing a lot of sanding on the inside especially, before applying the protective finish coat(s). Or maybe that would be done as the planks were sorted and the "logs" built.

I took the ResChek data file for our cabin and changed the wall type from conventional stick to log walls. I had to choose 5 inch thick walls as that is the smallest choice in the program. The three layer walls are actually 4.5 inch. With the 2x6 and R19 infilled walls we built, the plan comes out being rated 10% better than the energy code minimums. Changing the walls to 5 inch solid wood and removing the R-19 infill insulation the rating comes in as being 42% worse than energy code minimum, or more than 50% worse than our very conventional stick build.

An additional concern of mine applies mostly to weekend use cabins in winter. Let's take two similar buildings, one built like ours and another built with this "log" technique sitting there at cool to cold winter temperatures. Everything is cold. Which building is going to be warm and comfortable inside first? It's going to be the conventional stick build by a long shot. Thermal mass (thick walls) can work against you in buildings that sit unheated (or uncooled) for periods of time, with short periods of use (like weekends).

[MountainDon]

FWIW, I ran ResChek again with a 7 inch wall.
That received a rating 21 percent worse than code.
A 10 inch wall, double the original wall thickness, was only 4% worse than code.
A 12 inch wall receives a rating 2% better than energy code.
A 16 inch was receives a rating 11% better than code.


I am also not convinced that the method is easier or better for a novice builder. Most errors we see made here revolve around not thinking the process through from concept to finish, or plain poor design. I don't see changing from conventional to alternative altering that. This will be a much heavier structure than a stick build. Using "logs" like these is going to compound the foundation shortcuts that some builders have taken.  Other errors like non square corners, non plumb or wavy walls are still up to the care the builder takes in construction.

This method still uses a rafter or truss roof. Rafters seem to be one of the areas that cause novice builders a lot of concern, so "log" walls do nothing to change anything there. If one was to build a roof with a ridge beam, that might be simpler as the stack gable end wall would likely be strong enough to transfer the load from beam down to foundation.

So, my personal take on this method is one of "why". Any advantages, to me, are negated by things like poor thermal performance and electrical.

Keep in mind that REScheck uses climate zones and the zone where our cabin is, is one of the more demanding. Our cabin would pass REScheck with 7 inch log walls in many locations. Also, things could be improved with using smaller windows or windows with a better u-factor or more insulation in the attic.

[nathan.principe]

I get the feeling no one will be constructing one of these buildings any time soon! haha.....Well responses like these prove why you guys are the pros, and Ive always been a sucker for "out of the box" ideas, good discussion tho, I bet you ever read this thread ( including me) has learned something