With deference to Dana's expertise on insulation the only opinion on code that counts is your building inspector's. If a log home is all you can afford, I'd tell your BI that fact and ask him how to get it done. If log houses are part of the culture in your part of the world, as they are here in Pa, the answer may as simple as pine and a minimum 8 inch diameter. The logs are a static R 12. Thermal mass enhancement gets you the rest of the way to R19. http://loghomescouncil.com/docs/EnergyPerformanceWP_2010.pdf
I'd find someone with experience. My brother's log cabin is still tight and comfortable five years later because the Amish men who helped him knew logs and log construction.

Kudos for your initiative. And spare a thought for the men who built the many log houses in my part of the world that are still standing 180 years later. Black locust throws sparks when you tackle it with a chain saw. These logs were hand hewn. Square.

Posted By BadgerBoilerMN on 20 Apr 2012 08:35 PM
Of course they should be cured, but hey, you can't have it...for nothing. If he is using green logs open cell may work better, but how much will he have to use. With open-cell the vapor barrier will have to go on the inside of 2x4s and traditional build, but we haven't heard anything from Dan'l Boone for awhile. I think he wants to see the logs inside and out. Just talking to each other and the geo guy with the bad translating software...hheehehehehee

i'm still just beginning with my project. everything will be done right. can't cut corners with a log cabin, especially with my approach to it. your knowledge will make all my wifes ideas easier to manage :)

everyone has given me so much help and i haven't fully started it all yet. i appreciate it all so much. i'll be picking everyones brains for a long time, but not all the time.

Posted By webo on 19 Apr 2012 08:28 AM
...this is my first time building a log cabin,

How were you planning on constructing your log cabin?

I have a friend at work that is planning on building his own log cabin home.  He is building it on top of an ICF basement though.  For the log cabin, he went to a seminar on how to DIY build it.  He is planning on using butt-and-pass corners with rebar pins to lock the logs together.  He is planning on using ~12" diameter white pine for the logs.

I think his seminar was put on by these guys:  http://www.loghomebuilders.org/

Here is some discussion on the tightly pinned butt-and-pass log home construction under section 5 "Structural types of log homes":  http://en.wikipedia.org/w/index.php..._log_homes

Here is another site that discusses the DIY log cabin building process:  http://www.ourloghouse.com

You may have trouble meeting NY residential energy code with 8 " logs.  Not sure, but the way I read it, softwood is R 1.41 per inch.

http://www.energysavers.gov/your_home/designing_remodeling/index.cfm/mytopic=10170

Code here for climate zone 5 is R13 and climate zone 6 is R15 for a mass wall without the majority of insulation on the interior.

http://publicecodes.citation.com/st/ny/st/b1200v10/st_ny_st_b1200v10_4_sec002.htm

You may want to take a real good look at the energy code especially as it pertains to air sealing and insulation before you commit to a plan.

D1 agreed:
For the tightness may be there 5 years, but tell us in 10 then...

Seen the "soapy" foams CAN gap 1/4" or more off of sides of studs , in less than 2 years. Poly-U foams seen so far , just not as much. Been watching in last 3 years more sealing 1/2" poly-U with other types in front of that "rough seal" then not seemingly needing and erv, etc.

GeoThermal RADIANT with HW Priority also provides for Domestic HW WHILE producing Chilled water for a distant one, two, or whatever fan-coil, consoles, wall and closet hidden unit designs , too.

Vertical or Horizontal HVAC also has
HYDROZONE(TM) Hydro-Temp, (AR)
which shuts the fan off for a W:W chiller and hot fluid
which can be as with a PEX-INSULATED- loop to a same fan-coil for Both Cooling and Heating or a radiant zone nearer a particular fan-coil or console unit.
....

If I was going to build a Log Home .....this would be it-
http://everlogs.com/product_everlogs.php
energy efficient and no shrinkage

As you have perhaps realized by now, the latest energy code, IECC 2009, makes it much more difficult to build a log house. Used to be you could make up for less R value in the wall by adding more elsewhere. The code today sets a minimum level for walls, and requires houses to pass a blower door test for acceptable levels of air infiltration. The latter is not a problem in my view. I'd want to know if the wind will whistle through the walls.

But, for good or ill, local enforcement is all over the map. My friend caught a building inspector who gave him an r value of 1 for his log walls, and he squeaked by under the old code by shrinking windows and super insulating elsewhere. The next township over from me ignores blower door requirements.Your BI might be inclined to measure your logs at maximum diameter rather than minimum. Either way, you need know el pronto. If you need financing, the bank is another must stop. You have two strikes against you as DIY and log construction.

A suggestion and a caution if you are required to fur out interior walls and add insulation: Ask your BI if he is willing to divide your logs into compliant and not. Could be you'd get a bare wall or two out of the exercise. The caution is that the minimal insulation you'd need to add likely will net you zero energy savings. Because logs gain and lose heat slowly, bare walls will tend to keep things comfortable in spring and fall by averaging daily high and low temperatures. Covering the logs with insulation interferes with this process, and you may or may not save enough energy in the winter to make up for it. What's more, bare walls will buffer wood stove heat. If you must insulate, add as much as you can afford, and opt for a masonry heater over a woodstove. The web has countless sites on how to build your own.

A tip on sleeping lofts: It is going to be 20 or 30 degrees warmer than downstairs when you bank the stove and climb upstairs to bed. A ceiling fan is a boon then, but a bane in the morning when the entire house is cold. Consider a snap disk switch to turn it on and off automatically. Snap disks are cheap, reliable and come in a range of settings.

Posted By BadgerBoilerMN on 20 Apr 2012 08:35 PM
I would foam log to stud-at least 3.5". The logs will breath to the outside. They can fall off for all I care. Thermal envelope (and vapor barrier will be hanging from the studs). Of course they should be cured, but hey, you can't have it...for nothing. If he is using green logs open cell may work better, but how much will he have to use. With open-cell the vapor barrier will have to go on the inside of 2x4s and traditional build, but we haven't heard anything from Dan'l Boone for awhile. I think he wants to see the logs inside and out. Just talking to each other and the geo guy with the bad translating software...hheehehehehee

With 3.5" of closed cell foam, the foam itself is structural, and indeed the logs COULD fall off and the thing would still stand up, but you'd be losing 1/3 of the R value if  that happened, so y' ougtta care at least a little bit, from a thermal point of view.

With ~R10 of log on the exterior and ~R19 of open cell foam there would be no need for a separate interior vapor retarder in this location.  Open cell foam is air-impermeable but somewhat permeable to water vapor, but the moisture-susceptible interior face of the logs would have an average winter temp above the dew point of the interior air in this climate.  The higher-permeance of the o.c. foam would result in a higher drying rate the other 8-9 months out of the year. The logs themselves have about the same permeance/inch of closed cell foam, and at 8" thickness are a strong class-II vapor retarder inhibiting the inner face from drying to the exterior, and the drying toward the interior through 5.5" of open cell foam would be about 2 orders of magnitude higher than to the exterior.  (About 5-10 perms through the open cell foam compared to about 0.1-0.15  perms through the log.)

With 3.5" of  closed cell on the inner face of the logs it would be protected from wintertime moisture drives from the interior, true, but any moisture that found it's way to the inner face of the logs would never leave.  What would take a couple of months to dry seasonally through 5.5" of o.c. foam would take a few years through 3.5" of c.c. foam or 8" of wood.  With only 2" of c.c. foam it could still dry toward the the interior, but not nearly as well as through 5.5" of open cell.

In US climate zone 6 the IRC2009 calls out for R11.25 or more of exterior continuous insulation to be able to protect wood sheathing  from winter moisture drives through air-permeable R19 cavity insulation using only latex paint as the interior vapor retarder.  This location is on the warm edge of zone 6, and

A: open cell foam is not air-permeable, and

B: Solid logs have far better moisture tolerance/buffering capacity than OSB sheathing.

If the inspectors insisted on an interior vapor retarder, a class-II vapor retarder such as vapor-barrier primer  (~0.4-0.5 perms) would be far better than poly sheeting or foil.  Or...

...designing it for only 4.5" of o.c. foam rather than 5-5.5" would be a sufficient adjustment in the R-value ratio & dew-point calc to be fully protective of the interior face of the logs from wintertime moisture accumulation with only standard latex on the interior.

We have to presume perfect chinking and future maintenance...on green logs. But I will go along with the open cell if our pioneer can afford to give up the interior space...and the foam. Last year we did a major remodel on a block home (no insulation). With condensing boiler and old cast iron radiators, the fuel bill did go down, but plastered inside and stucco out left no alternatives. Sometimes a fellow just has to chop more wood. As for the code, a fella out to do as he can first and do as he must when he can.

RE the other discussions of ceiling fan in to move stove heat... bury the snap disc electrical exposed- in similar to electrical silicone for any moisture concerns- this survived many years inside air-solar collectors for shutting off/on - in line with a stat.

some apps:
One will find a small 4- 6" ducted fan , decorated- hung to blow stright down (a cross of metal in the air stream with a wedge-shaped 1/4"-3/16ths thick trailing edge out of a reducing nozzle- ie) 6x4, 4x3)~` 35-40 watt motor (sealed refg style) will more effectually ram heat at ~` 3 ft per sec to the floors in a column such that you will think the floors have radiant heat to 8-12 ft radius-ing outward and turning over the air niceley. ( Ducted fan can be right by the fly-pusher used then in intermittent weather ht-to-clg , ... a bit).

i plan on havin my kitchen in the loft area to keep from running water through the whole building. i'm considering going with 12" thick logs instead of 8, as long as i have enough on my hill. that should up my r value a considerable amount? i think the trees are ash but i'm not sure,won't know for sure until the leaves are fully out. i'm in the process of talking with my building inspector about the exact guidelines i would have to follow. once i know all the "nitty gritty" of what i need to accomplish i'll be ready to actually draw up the plans and get this project going.

Hardwoods have less insulative value than softwoods: 0.88-0.94 R per inch specifically for ash. So you have the same problem of close but no cigar.Again, the only opinion that counts is your BI's. As an alternative, a sawyer could back a Wood Mizer portable sawmill onto your property, cut enough lumber for a good sized cabin,and leave a much smaller hole int the canopy than log construction. Around here, which is forestry country, the sawyer gets 28 cents a board foot; the kiln operator 30 cents a bdft; and the planingmill 7 cents a foot for truing up. Your costs will vary. You still need the BI on board. Technically, you can only frame with lumber stamped SPF 2 or better. But, if logging is common in your area, the BI will recognize that ash is far superior to SPF,with a beautiful grain to boot.

To be clear, cutting your own lumber won't save much if you use standard stud wall construction. A 2x4 stud is about 3 board feet, so at about $2, it's roughly the same cost, albeit inferior in quality. But cut into beams for timberframe, mill your own is substantially cheaper. If the blue stone you are talking about is Pa blue slate (a flagstone essentially) and free, a half timber design with stone inside and out, and reclaimed polyiso in between, would be worth the effort.

One thing I don't think you'll escape from in an area governed by ICC (such as New York) is an automatic heating system requirement.
You can heat with wood but still must have an automatic system in place- perhaps electric baseboards vs the portable heater you mention.

True log homes look cool to most everyone that hasn't lived in them. Why not split your cut away timbers for log siding? It is a good comprimise.

Good Luck.
j

Dunno how many planing mills would have the knives to cut log siding. And a stud wall house isn't free. Unless.... Anything need tearing down in your part of the world? Around here second home log cabins rarely have automatic heat. Youd probably have to show that you can drain plumbing and such so it can be left unattended. Again, you BI is the man.

Posted By toddm on 26 Apr 2012 11:47 AM
Around here second home log cabins rarely have automatic heat. Youd probably have to show that you can drain plumbing and such so it can be left unattended. Again, you BI is the man.

Hmmm so an inspector who ignores the code? Or a cabin not consider occupied space? A New York amendment? Old pre ICC buildings or buildings who's furnace failed never to be replaced? 

Or an unsubstantiated claim? How do you know?

Not trying to be combative, but you used the term rarely. The inspector in me would be offended by a cowboy that ignored this rule as mortgages want central auto heat as well. No mortgage, no re-sale, no value.

 

NYS does have this exemption which, I believe, still exists:

http://www.dos.ny.gov/DCEA/pdf/TBhuntfishcab.pdf

Not sure if this is what the o.p. had in mind though. This would be for a limited use cabin with no access to utilities.

I may have mis read, but it appeared OP was building a dwelling.

My thoughts too. Just thought I'd post that in case a better use for his logs might be a cabin in a remote area as opposed to his main house. That exemption was mainly to appease people building cabins in the Adirondack park when NYS made it mandatory to put in a well and septic for a dwelling. Got extended to the rest of the state as well. The building still has to structurally meet code, tho.