Author Topic: Alaskan remote 16x28 1.5 story in a Winter Wonderland  (Read 22362 times)

0 Members and 1 Guest are viewing this topic.

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Alaskan remote 16x28 1.5 story in a Winter Wonderland
« on: January 19, 2016, 10:21:07 PM »
I reckon it's time to de-lurk and announce myself on the forum.  Hello from Chugiak, Alaska!  The light of my life and I are buying some land near Lake Louise, a popular destination for fishing in summer and winter, in the Copper River basin in southcentral Alaska.  Before I jump into our plans for the cabin let me show you the lay of the land.

Driving along Lake Louise Road looking north at Lake Louise


Looking east over our unnamed lake towards the Wrangell Mountains


Looking south from the same location.


We're about nine miles from the end of the road.  Half of that is crossed by snowmachine* on the frozen Lake Louise, and the remainder is by existing trails and a new trail of about three miles that I will have to clear myself.  In the summer we'll be using a local air taxi to land us on the lake.

*Alaskans refer to snowmobiles as snowmachines.  Don't ask me why, it is what it is.
My cabin build thread: Alaskan remote 16x28 1.5 story

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #1 on: January 19, 2016, 10:49:55 PM »
Our current thoughts are on a 16 x 28 stick frame build with a half loft.  The knee walls will be at least 4' giving lots of livable space upstairs.  Here's a mockup, please excuse my poor Sketchup skills.



There is discontinuous permafrost throughout this portion of the Alaska.  The area was once under Lake Ahtna, a Pleistocene glacial lake that left behind lots of sand and silt, and some gravel.  I don't yet know what's on the property but I am planning for the worst and designing a pad and post foundation that can be adjusted as the ground moves to frost heaving or permafrost thaw settling.

Other than that all design considerations are provisional at this time.  There is no permit authority to contend with, but I plan on building something that will last as well as be within the guidelines of the IRC.  I have given some though to using three-sided logs, as I find the look very appealing.  They don't fare too well in the insulation department, but this will be a recreational cabin that will see many weekends of use in the winter and a few weeks of use each summer.  The biggest reason for me at this point not to use milled logs is the cost.  There are some nice sized spruce on the property but I doubt very much there is enough to make cutting and milling my own feasible.  We'll see on that issue.

Otherwise my thoughts are for 2x6 construction, T1-11 sheathing, and a metal roof with a 12:12 pitch.  Snow ground load here is 70#, and I like the idea of having a roof that will shed some of that snow.  I'm designing for a cathedral roof with a ridge beam to support the rafters.  The ridge beam will be supported by some timbers.  Also thinking of having the loft floor be 2x6 tongue and groove decking on timber joists.  To keep stairs from eating up too much space we'll have an alternate tread staircase.,

That's a few of my design considerations and I'll be dumping a lot more on you all in the near future.  We're set to close on the property later this week, so I may be getting a little ahead of myself making too many plans before we even own the land.  But winter will be the time to haul in materials so it'll be a mad rush once the ink is dry on the deed.
My cabin build thread: Alaskan remote 16x28 1.5 story

Offline nailit69

  • Full Member
  • ***
  • Posts: 175
  • Welcome to the CP-Forum
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #2 on: January 20, 2016, 03:07:40 AM »
Sounds like a fun project... looks like it's way the hell out there... love that east view.  In my opinion, you can never start too early, I think it allows you (me) to get the bigger picture of what's going to be happening and also allows you to keep an eye out for things you might be able to use out there.

I'm building a similar sized cabin (14'x24') just south of the border of BC Canada and it's going to be a long project so it gives me a chance to gather other things i'm going to need out there.  My foundation is in and ready to build on but I've also been grabbing water tanks, a generator, propane tanks, on demand hot water, gas cooktop, woodstove, plumbing and electrical materials, nails, hangers, looking into solar/wind, etc..  I need about $8k in lumber and materials just to get it dried in and sided and i'm keeping an eye out... for a 25' ridge beam in particular MSRP $950... so any jump I can get on that is huge.

Looking forward to seeing more of your project... after the snow melts i'm guessing?  That's where im at... waiting on 2'-3' of snow to go away.
« Last Edit: January 20, 2016, 03:25:42 AM by nailit69 »

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #3 on: January 20, 2016, 07:24:43 AM »
I'm going through that same process myself.  Trying to think things through too far ahead of time can get me wrapped up in minutiae though.  Was pondering last night about how to provide light and power.  Originally I was thinking about DC lights, like using RV fixtures.  Then I realized that AC wiring and fixtures are a lot more available and affordable.  With a small capable inverter like the Morningstar SureSine 300 I can cover most of my needs and save the heavy stuff for the generator.  A big 105 amp-hour battery or two to store energy and a couple solar panels for about 400 watts is what I'm thinking.  Just starting to read up on this stuff but one suggestion was to get everything else working before you consider wind.  It's typically too expensive and unreliable for most users.
My cabin build thread: Alaskan remote 16x28 1.5 story

Offline kenhill

  • Full Member
  • ***
  • Posts: 196
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #4 on: January 20, 2016, 11:50:10 AM »
With the majority of use in the winter and the -30 degree temps you get out there, I would think you would be better off with 2x6, insulation and tight construction.  We are at Red Shirt lake and when it is 0 out there, it can take all day for my 18,000btu oil stove to warm the 20x30 up to 60 degrees.  I would suggest a good wood stove to heat faster.

Many people use the pad set up in that terrain.  I hear a 2 foot by 2 foot box made out of 2x12 works well.  Otherwise, might want to look into the auger style piling.  Whatever you do, don't skimp on the foundation, the rest of your financial investment depends upon it.

Offline nailit69

  • Full Member
  • ***
  • Posts: 175
  • Welcome to the CP-Forum
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #5 on: January 20, 2016, 07:19:29 PM »
I'm going through that same process myself.  Trying to think things through too far ahead of time can get me wrapped up in minutiae though.  Was pondering last night about how to provide light and power.  Originally I was thinking about DC lights, like using RV fixtures.  Then I realized that AC wiring and fixtures are a lot more available and affordable.  With a small capable inverter like the Morningstar SureSine 300 I can cover most of my needs and save the heavy stuff for the generator.  A big 105 amp-hour battery or two to store energy and a couple solar panels for about 400 watts is what I'm thinking.  Just starting to read up on this stuff but one suggestion was to get everything else working before you consider wind.  It's typically too expensive and unreliable for most users.

@Chugiak... My lights and power will start off with a traditional AC electrical system and run off the genny to start with, then i'll probably add a solar system w/batteries and an inverter as I can afford it, and finally a small wind generator just for maintaining the batteries when it's cloudy... just cuz the wind seems to be the only constant up there.

@Kenhill... I agree with you 110% on the foundation... that's the hardest thing to fix if it's not done right, mine is a cement block 6'-4" "crawlspace" with a floor hatch and a set of double doors to the outside.  I'm also going with 2x6 double wall construction, the most R-value I can stuff in it and a kickin' woodstove to keep it warm.

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #6 on: January 21, 2016, 02:00:22 AM »
The three biggest costs I've come up with are the foundation, the roof, and the stove & pipe.  Three places where it pays to do it right.


Sent from my HTC One using Tapatalk

My cabin build thread: Alaskan remote 16x28 1.5 story

Offline nailit69

  • Full Member
  • ***
  • Posts: 175
  • Welcome to the CP-Forum
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #7 on: January 21, 2016, 06:41:10 AM »
The three biggest costs I've come up with are the foundation, the roof, and the stove & pipe.  Three places where it pays to do it right.


Sent from my HTC One using Tapatalk

Ya, my foundation came in around $3500 but I went a little overboard and that included the mini excavator rental, but it's bombproof.  It's cement block filled solid with rebar and concrete... it's not going anywhere. 

According to my budget/bids my next and biggest expense is framing package/roofing/windows and siding at around $9k realisticaly speaking.  This years goal anyway... framing and roofing at a minimum, and that's still coming in around $3500-$4000.  Fortunately for me, i'm a carpenter so I don't have to pay any labor... well, not that much anyway... it always costs me beer and gas up there.

That triple wall stovepipe can be spendy... last time I bought it, one 3' section was like $90... I need at least 2 sections and a ceiling box.  I've got a great little airtight woodstove that i'll probably use up there, I hope it will be enough to keep my 350 sqft nice and toasty when it's -15.

After that, the next big ticket item will probably be my solar setup... which I don't really have any real hard numbers for as of yet, but i've heard the general rule of thumb is about $1 per watt for a good setup.

Sidenote:  Not sure if it's the case where you are but after comparing the two, T1-11 siding was more expensive than using OSB and 8" Cedar Channel Siding which is going to give you better construction and a more rustic look than T1-11.
« Last Edit: January 21, 2016, 06:55:01 AM by nailit69 »

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #8 on: January 21, 2016, 11:38:21 PM »
Thanks for the pointer on siding.  Part of me wants to do self milled board and batten siding, but I'll look into that cedar channel.  I'm not against using OSB for sheathing.

Sent from my HTC One using Tapatalk

My cabin build thread: Alaskan remote 16x28 1.5 story

Online Don_P

  • Journeyman
  • *****
  • Posts: 4,082
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #9 on: January 22, 2016, 09:09:46 AM »
there's a couple of ways of looking at the ridgebeam support. It can be supported by the gable end walls and overhang the end porches, certainly can be done but might get into a larger beam.

You've drawn the beginnings of a truss in the gable end of the porch. Actually making that a load bearing truss it can then support the end of the overhanging ridgebeam. If there is a post or truss about the middle of the building then the supports are truss, gable wall, post, gable wall, truss... the ridgebeam has nice relatively short spans and can be smaller.

The connection at the heeljoint in a truss is under the greatest "thrust" as the top rafter chord,  which is now trying to support a substantial accumulated ridge load, is driving down and out with the load pushing on it from above.
This is one way of restraining that thrust in a heavy timber truss. The "relish" in the bottom chord beyond the notch is trying to shear off, it is sized accordingly.


I put a couple more reinforcements in that particular joint. The post tennon passes through it and there is an allthread rod holding the joint together.


Then look at the kingpost. A kingpost is really a rope dangling from the peak and holding up the bottom chord from sagging. My truss needed a bottom chord that was longer than I could saw so I passed a spline through the kingpost and pegged the spline to the bottom chord members on each side of the king.  The bottom chord is also a tension member, it can be thought of as a rope.

Here is one way to look at it. As you push down on the roof it tries to spread. The bottom chord goes into tension and resists that spreading force... up to the quality of my string and knots.
The kingpost dangles from the ridge and keeps the bottom chord from sagging.


In the drawing above notice that it is pinched in a kind of Chinese finger puzzle, the greater the load the tighter the kingpost top joint pinches on the king.

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #10 on: January 22, 2016, 08:39:28 PM »
Hey Don_P, thanks for the insight on truss dynamics.  Or is that statics? d* 

You've intuited my plan pretty well.  I'm actually looking at having two vertical supports inside, so it would go end truss, gable wall, post, post, gable, wall, end truss.  Max unsupported span for the ridge beam will be a sniff under 10 feet.  My mockup of the end truss was not by design, I am just copying what I see everywhere else.  Now I know why it's so ubiquitous.  I came here hoping to get some guidance on incorporating timber construction into my cabin and blamo, I get it without even having to ask.  Thanks much for the sharp eye and comments.
My cabin build thread: Alaskan remote 16x28 1.5 story

Online Don_P

  • Journeyman
  • *****
  • Posts: 4,082
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #11 on: January 23, 2016, 06:10:32 AM »
Some of us are quite free with unsolicited commentary  :)
What you drew is a very common way of building that porch detail if it is not completely understood, I own that shirt  ::). Without a really good heeljoint connection the kingpost ends up trying to hold the ridgebeam up, a heavy job for the bottom chord at ~ a 15' span. My understanding is that would be classed as a crownpost frame, a predecessor of the kingpost truss. Around the 15th century the porch light came on for some builder and away we went.
It's workbench statics, and you just gave another puzzle piece we can play with, sizing the ridgebeam.
At 16' wide the rafters each bear half on the wall and half on the ridgebeam. The opposing rafter also bears half its load on the ridge and half on the other eave wall... so the load distribution is 1/4 bearing on one eave, 1/2 on the ridgebeam, 1/4 on the other eave wall. 8' of tributary width x 10' of ridge span x (70psf snow+10psf dead load)=6400 lbs on a 10' span. A triple SPF 2x12 or a single 11-7/8" LVL would work for the ridge.


Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #12 on: January 23, 2016, 11:02:01 AM »
The roof will overhang by 2' or so, so wouldn't the load calc for that be 10' x 10' x 80 lbs/sf = 8000 lbs?  Does that alter the beam size?  Wait, my coffee is starting to kick in.  The eave snow load is relevant for ensuring the wall and foundation are adequate but since it doesn't bear on the ridge beam it can be ignored here.  If anything I suspect there is some cantilever benefit that lessens the load on the ridge beam.
My cabin build thread: Alaskan remote 16x28 1.5 story

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #13 on: January 23, 2016, 11:26:05 AM »
My ridge beam as planned will need to be 44' long.  I haven't yet looked into LVL cost but the longest I've seen listed on the internet was 40'.  Given that everything will be coming in over the snow towed on a sled, I have doubts about even hauling something that long.  So I think for now I will plan on constructing a 3-2x12 beam on site.  That won't give a rustic timber look for the porches but I think I can live with that.  We'll see what the LOML thinks about it.

Along that vein, for the floor girders I am thinking of going big, as in a size or two more than the minimum dimensions indicated by the span tables.  My thinking is that when there is ground movement, the cabin will move as a single stiff object rather than flex and deform over frost heaves.  If this is even a rational strategy to pursue, I suspect I'll have to also stiffen up the floor joists in a similar fashion.  What I don't know is if there is actual benefit to building like that, and what might the costs be (structural, not economical)?
My cabin build thread: Alaskan remote 16x28 1.5 story

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #14 on: January 23, 2016, 11:54:25 AM »
So if I move the tie chord up to form a proper truss, like so...



then I need to make sure that I've got connections that hold in tension for every joint.  Essentially on the end truss the rafters are holding up the ridge beam rather than the other way around?  If that's the case I need to rethink the rafter/beam joint.
My cabin build thread: Alaskan remote 16x28 1.5 story

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #15 on: January 23, 2016, 12:21:02 PM »
So here's as far as I got on trying to use the IRC for designing the cabin.  Erred on the side of caution with live and dead loads.  I think 2x12 headers may be more than is needed on some of the wall openings but it makes the math real easy.   [cool]

Code: [Select]
Load design
Main floor, 16x28 (448 s.f.), dead load 15 psf, live load 40 psf = 24,640 lbs
Loft floor, 16x19 (304 sf), dead load 15 psf, live load 40 psf = 16,720 lbs
Roof, 20x44 (880 sf), dead load 20 psf, live load 20 psf, snow load 70 psf = 96,800 lbs
Decks, 360 sf, dead load 10 psf, live load 40 psf = 18,000 lbs
Total load = 156,160 lbs


Pads
Soils may not be capable of supporting greater then 1500 psf
Design load of 156,160 lbs requires foundation footprint of 105 s.f.
Treated timber pads of 24 x 18 yield 3 sf of supporting area.  This is extended by depth of compacted crushed gravel
A 36 x 30 crushed gravel bed 6 deep provides 7.5 sf of supporting material.
A minimum of 14 pads are required to support the structure.

Posts
Assuming a compressive strength perpendicular to grain of 335 psi, 6x6 horizontal pad timber can withstand 12,000 lbs
Assuming a compressive strength parallel to grain of 525 psi, 6x6 vertical post can withstand 18,900 lbs

Girders
A constructed beam of dimensional lumber must be fastened in accordance with R602.3(1)
Center beam is bearing load transmitted through the interior support timbers
Per R502.5(1), 70 psf snow load, a beam of 4 2x10 can support a span of 7' 7
Posts under main floor placed 7' on center have maximum span of 6' 6
With additional post and pad under interior load points, total of 23 posts

Floors
Main floor joist span of 7' 3
Per R502.3.1(2) with 20 psf dead load, #2 or better, 2x8 on 24 allows span of 9' 3
Blocking at center beam and along header joists
Extra blocking at load bearing wall, under wood stove

Walls
Per R602.3(5) for bearing walls supporting roof and a floor, 2x6 on 24
Jack studs under interior timber and at gables under ridge beam
Door and window headers 2x12 sandwich with foam core

As shown in the first sketchup image of the whole cabin, I've got a lot of pads to dig.  I think it may be worthwhile going to 2x12 girders so I can increase the span and drop the number of pads.  Costs will probably be a wash but the savings in lessening the amount of pad preparation will be worth it, I think.  That is a strategy I read on an Alaska cabin forum, have fewer posts and pads so that there are fewer places for the heaving ground to torque the floor around.
My cabin build thread: Alaskan remote 16x28 1.5 story

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #16 on: January 23, 2016, 01:36:41 PM »
One more post before I try to do something productive today.  I'm looking at the 2012 IRC here.  Looking at Table R502.5(1), I am using a snow load of 70 psf and a building width of 20 feet.  My plan has a center girder supported by posts, two posts and load bearing wall supporting the loft, and two posts supporting the ridge beam.  The way I read the table I should be looking at the Roof, ceiling and two center-bearing floors section.  Accordingly, a 4-2x10 girder allows an unsupported span of 7' 7" and a 4-2x12 girder allows an unsupported span of 8' 10".

Here's a mockup of the new pad spacing of 7' 11".  I've nudged a couple over along the center girder to line up under the interior support posts.  I've also shown the load points with the colored beams to represent where the roof is supported.  You can see that using this spacing the gable wall load points do not have a post directly under them.  These are highlighted in red.  This concerns me, as I don't remember how much offset is allowable.  The solution may be to add in two more posts.  The pad under the post in green is as close as I can get to the interior load bearing post using a 16' 2x12.  Is this amount of offset (6 inches) sufficiently small to transmit load to the foundation?

My cabin build thread: Alaskan remote 16x28 1.5 story

Online Don_P

  • Journeyman
  • *****
  • Posts: 4,082
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #17 on: January 23, 2016, 04:52:41 PM »
Bingo on the eureka over coffee, The slight cantilever effect is there but I haven't seen anyone use it in dimensioning members etc. Dutch barns made use of a balanced rafter... squirrel.

This is a kingpost truss supporting the ridgebeam from underneath



Visualize the lower 2' of the kingpost gone (yup I could whack it out) and the ridge load driving down the top chords of the truss. You need a very strong connection between the bottom chord and the lower part of the top chord. I used that same notch on these but there are any number of ways to restrain this, the greatest force in the truss.



An unassembled shot of the kingpost to show the joggles and mortises in the top and the tennon that went into the bottom chord and was then pegged to support it. We built a temp floor on the bottom chords to do the ceilings, the kingpost holding the bottom chord up allowed that kind of load.



Basically the red posts are a no go, the green one will work, load can travel up to 45 degrees without changing to cantilever conditions... it can offset as much as the girder depth, go carefully if it is heavily loaded. Make the girder deeper and free up to move supports.

Being on unbraced piers there is nothing keeping them vertical, frost and seismic issues, looks like the wind has quite a fetch as well. Find a way of doing more than the 2x brace slapped on as an afterthought. I'd be more tempted to build a crib of timbers on a leveled gravel base but local wisdom rules in situations like this.

Online Don_P

  • Journeyman
  • *****
  • Posts: 4,082
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #18 on: January 24, 2016, 07:20:59 AM »
Googling images for "stabbur", this is a nice example of the traditional Norwegian mouseproof storehouse.


The long stiffening element that you are trying to pick up at the girder is usually created by the continuous perimeter foundation. The foundation also should be braced laterally. A timber crib is forming that stiffening foundation element and bracing the piers in this old cold weather foundation.

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #19 on: January 25, 2016, 10:49:18 AM »
...
Being on unbraced piers there is nothing keeping them vertical, frost and seismic issues, looks like the wind has quite a fetch as well. Find a way of doing more than the 2x brace slapped on as an afterthought. I'd be more tempted to build a crib of timbers on a leveled gravel base but local wisdom rules in situations like this.

I've been pondering that issue for a while.  My initial go-to reference for building on permafrost has been this reference from the Cold Climate Housing Research Center in Fairbanks, Alaska.  In discontinuous permafrost the biggest concern is settling due to the thawing of ice, especially ice lenses.  If I were on the highway I could probably make frozen slurry piles effectively and affordably.  For remote, the most common practice is a surface foundation using post and pad construction.  To keep air flow to a maximum beneath the structure I want at least 2' of clearance above the ground and no skirting around the cabin.  This will keep frozen ground frozen, in theory.  All these concerns about permafrost would be moot if I knew exactly what was under the surface.  A proper geotechnical investigation would answer all questions but probably cost more than the land and cabin together.

So until my plan changes I'll be putting the cabin on posts about 3' long.  That will make things wobbly, and since we just had a 6.8 earthquake up here this weekend it is important to brace the uprights very well.  I was thinking of using steel tubing for cross braces rather than the usual 2x6.  I don't know where to start as far as determining what the specs for that would be, but it seems a good way to get the lateral bracing and keeping air flow resistance to a minimum.
My cabin build thread: Alaskan remote 16x28 1.5 story

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #20 on: March 14, 2016, 11:27:12 PM »
Still so many things to figure out on the cabin design.  For now, we have got a place to stay on the property that should keep us dry and warm.  I've cleared a trail to the property and have put up a Weatherport shelter.

Loading up lumber for the platform.


Hauling the beams and some pallets.


Clearing snow away and digging spots for concrete piers.


Got the beams in place, sort of.


The joists are framed up and the plywood floor is going down.


Jump ahead to completion of the Weatherport.


They say in Alaska if you want to get some friends, buy a boat.  If you want to find who your friends are, have them help you build a cabin.  Here's a true friend, hopefully she'll come back and help when we start the cabin...

My cabin build thread: Alaskan remote 16x28 1.5 story

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #21 on: March 14, 2016, 11:46:37 PM »
Looking at a few design changes.  Scissor trusses instead of ridge beam and rafters, and dropping roof pitch from 12:12 down to 9:12, with a 6:12 pitch on the lower chord.  I've been playing with the HomeBuilder and MedeekTruss plugins in SketchUp.  Wow, do these tools make it quick and easy to gin up a house frame in just a few minutes.

I know I can't be the first person to encounter this problem.  I'm looking at having 6' walls for the second floor.  Platform construction for the back half of the cabin, single wall ala balloon framing for the front.  That puts my side walls at 15', and the gable wall
tops out at just over 21'.  Here's a snapshot:


The IRC says I can go up to 20' on a non-loadbearing wall using 2x6 at 12" o.c.  With trusses the front wall isn't load bearing except to support the porch roof.  So in theory I shouldn't have a wall higher than 10'.  Clearly there are plenty of houses that have tall walls, so I'm wondering what solutions people employ.

Edit: I am aware of the need for fire blocking on the tall walls.
My cabin build thread: Alaskan remote 16x28 1.5 story

Offline MTScott

  • Apprentice
  • *
  • Posts: 15
  • Welcome to the CP-Forum
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #22 on: April 06, 2016, 11:32:14 AM »
As for wall height, I've wrestled with this same concept myself.  I wanted to run 12' studs all the way on he supporting walls, but still have an open area in front of the loft over the great room.  The key is "unsupported".  If you had a complete second floor you'd be fine.  My plan is to run a 12/12 pitch over the great room area, with 10' walls, and switch pitch over the loft area to 8/12, or maybe 6/12.  Effectively, I'll build a full second story over the loft, but maintain a single ridge line.

I haven't found a way around the 10' wall height... well, other than have a structural engineer approve your plans.  As far as code goes, there isn't a slam dunk answer.  In truth, you'd probably be fine, but you might want to run 2x8 studs; however, the answer I arrived at is if it doesn't meet standard code it probably can be done, but you'll need a PE's signature (If passing an inspection will ever be a concern, or if you want to sell it one day).

Offline ajbremer

  • Senior Member
  • ****
  • Posts: 830
  • Mounds, Oklahoma
    • Al and Robins 14x24 in Mounds, Oklahoma
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #23 on: April 06, 2016, 04:12:25 PM »
Very nice ChugiakTinkerer!...I'll keep looking - Alaska sure is beautiful.
Click here to see our 20x30 and here to see our 14x24.

Offline ChugiakTinkerer

  • Senior Member
  • ****
  • Posts: 437
  • Building a remote cabin in Alaska
Re: Alaskan remote 16x28 1.5 story in a Winter Wonderland
« Reply #24 on: April 17, 2016, 09:11:22 AM »
How does that saying go?  Life is what happens while you're busy making other plans.

My grand scheme involved hauling out all the materials to build over the winter, and miraculously putting it up in a week or two this summer.  I have to say I have been receiving a valuable lesson in remote site logistics, and it is quite humbling.  The Weatherport structure I could probably have put up in a weekend in my back yard.  One day to put in the platform and another to put up the tent.  Reality made short work of my expectations however.  Instead the time to haul materials on site was a lot more than I assumed, and just the ability to get on site and get some work done is severely limited.  When we were staying overnight at the lodge, the longest work day on the property was 4 hours.

Winter took an early departure this year.  I went up to Lake Louise last weekend with the hope of getting in one more load of material.  I got there at 9 am expecting it to be about 20 F, but instead it was 33 F.  That meant the trail did not freeze up overnight like I hoped, so I opted not to get myself bogged down in slush and muck.  Drop back ten yards and punt the ball.

My revised grand scheme is to spend a week this summer putting in an outhouse, a floating dock, a stoop for the Weatherport, and a tent platform for guests.  I'll save construction of the cabin for next year.  This will give me an opportunity to site the cabin and do the digging necessary to have good footings.  This will involve putting in a lot of gravel material, which is a subject deserving of its own post.  I'm hoping we can find some good gravel at the top of the hill where the birch trees are growing.
My cabin build thread: Alaskan remote 16x28 1.5 story