Peaceful Ambitions - 14 x 24 House

Started by Peaceful Ambition, March 20, 2017, 04:45:24 AM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

Peaceful Ambition

Hey everyone I've been lurking and learning here for a LONG time and I'm very excited to finally be able to contribute a thread of my own!  We're going to be building the 14x24 Little house plan this summer and I'll be posting plenty of pictures and keep you all updated with hope that not only will you enjoy it but that many pairs of eyes checking my work could potentially save me some headaches!

A little background...I live in an area in the west which can get quite snowy, the snowload map for our property says snowloads can reach 40-60lbs ( thats if I'm looking at this snowload map right, It may be less). Wind gusts in the area can reach 75 mph although we have trees on our windward side so I don't know how much we actually get.
I want to build the house as strongly and safely as possible and it's been our dream to build our own place for a while. I'm extremely glad a resource like this exists online. I am a complete newbie though so please forgive me for asking any rediculous questions. d*

-------------------
So here is where I'm at so far:
I am having a contractor/friend do the 16x16x16 footings and getting them square because If I mess up I really don't want to have to dig one of those suckers out.

Walls will be done with 2x6 studs and hopefully 10' tall if I can figure out the loft.

After reading about cantilevers and because the plans extend 2 feet out from the beams (and considering our potential snow load) I am probably going to be changing the joists to either 2x8 or 2x10s at 12'' or 2x12s at 16'' just for the extra peace of mind.
We will be doing a metal 12 in 12 roof so I doubt the snow load will get that high but I'd rather be safe than sorry. What would you suggest?

As previously stated we'll be going with the 14 x 24 little house plans, very inspired by the Nash house
http://www.countryplans.com/nash.html
specifically the amount of headroom in the large sleeping loft. But I'm confused when looking at the pictures of that loft, and comparing them to the plans and what I've read in many other threads on this website.

The plans call for two partial lofts (we'll probably just do the large loft) and a cathedral area in the middle, but from my understanding, unless you are tieing the walls together with a full length loft, rafter ties are required for the entire length of the house due to roof thrust.
It seems like in the LH plans the loft joists ARE the rafter ties. If this is so, how is the nash house able to safely use 10' walls with only collar ties over the open area? ??? Do the little house plans do this as well? I can't tell because the diagrams only show the rafters from the ends/corners.

I also notice the nash house has a beam right in the middle of the large loft to help support it, is this required or just there for some extra support? Does the beam go through the floor into a footing or is it just tied into the floor joists?

I realize thinking about the roof before I even have the walls up may be putting the cart before the horse but I really want to have a clear mental picture of what we'll be doing before I start.

We're waiting just a few more weeks for the rest of the mud on the road to dry before the footings will be done but I will post some pictures of the site soon!
Thanks for reading this far. See ya soon
You are not illiterate

Don_P

 w*
Headache #1, well, I can be polite or I can be honest. I'll be honest but it is not with the intent of being impolite. When you choose to build illegally, don't spend more than you can lose. You inquired about a 120 sf house and plan on a 336 sf house, it may pass. If the house is "caught"... and I'm not sure how people expect to hide an elephant in their yard for a lifetime, the inspector will probably want to inspect it and anything not built right will need to be brought up to code, or he can simply have it removed and send you a bill for that. When I say "code" generally what I'm really talking about is rational design based on physics and experience. I'm not enforcement and don't have a dog in it, just seen people do it to themselves before. I've also seen contractors get caught in the middle of a situation like this, lose their license and their "friend" leaves them flapping in the wind. Not too long ago a friend of mine was busted, the homeowner had talked him into working on an unpermitted house. Another contractor that had bid the work turned them in. That guy is a jerk and there is a good old fashioned case of karma coming down on him but he was not wrong either, you never know where it is going to come from. There is an old saying "a wise man learns from the mistakes of others, a fool from his own". I don't think that needs further discussion, your call on how you proceed.

Actually most people put the cart before the horse by not looking at the roof first, that is the correct order to trace the load path. It sounds like you've read enough to know that this roof is not properly tied. You asked how this could be done safely and you know enough to know that what you are looking at isn't safe. One solution is to hang the rafters from a beam at the ridge. A 24' beam would likely be too massive to afford or handle. I would try to use a post from around the center of the ridgebeam down to a properly sized footing. It can also pick up a loft support beam if needed. Another way is to use trusses. You posted a footing size but as yet I don't think you know the loads on the footings, that is putting the cart before the horse.

A pier and beam foundation should be engineered, I've not spoken to an engineer who would sign off on the ones we see pictured here. A post frame also requires engineering but it is something that they can approve. The posts would not be inset in that case, they would be on the perimeter and would run unbroken from footing to top plate. Building prescriptively is another way.


Peaceful Ambition

#2
Don, thanks for your concern!

Regarding the build process,  when you say that the roof is not properly tied, are you referring to the nash house or the LH plans as designed? I see a cathedral style ceiling in the LH plans as well although not with the extra headroom the nash house has.

I don't think I'm up for converting the roof to a ridge beam plan, so I may wind up looking at trusses or just leaving the plans as they are in that regard.
Would trusses would allow me the ability to notch in a ledger board and start the partial loft at around 8' on 10' walls  and then have the rest of the house be a cathedral style without creating outward thrusting forces? How are trusses generally lifted, with a crane or are they not too crazy heavy?

I am unsure as to the loading on the footings and I am just going with the contractors recommendation after showing him the plans, we have relatively rocky soil.

What do you think my idea for the floor joists? Do those seem sufficiently beefy for my needs? I'd rather be overkill than under. I understand the best you can do is speculate and an engineer would have the most accurate answers but unfortunately I'll be doing this without the guidance of an engineer.
You are not illiterate

Don_P

#3
I've brought in and set trusses up to about 24' by hand, as well as beams up to 40'. The truss shop printout will have the weight of the truss on it. A number of those shops also deal with post frame buildings and do the engineering as part of the sale. Equipment certainly makes things easier but the ancients were pretty sharp, simple machines work. The "I'm not up for" out of hand dismissals exist in a place between our ears, do recognize that. It limits our options when we start down those thought paths "I can't" vs "How can I". We've also put boom trucks and cranes in some pretty tight places in these mountains, those operators are good and generally not that expensive.

Check out post #88 here;
http://countryplans.com/smf/index.php?topic=14235.75
That is one way to tie the rafters using the floor joists. I would make the birdsmouth notches a good bit smaller than in the drawing to preserve more strength but that concept is much stronger than what you're looking at doing.

Scroll up to post 77 to see a post frame. With the posts extending from footing to top plate there is not a pinned hinge supporting the building, the support posts become braced cantilevered beams.

For floor joists you can check them in the code tables, remember those tables are minimums. I'm not going to check them at this point because the design isn't correct yet. Remember overkill in one part of the chain does not correct the weak link in another part of the chain.

Edit;
Running back up on the roof with that "how can it be done" attitude, lets see how big that ridge beam would need to be. I'll assume there is a post at midspan breaking the ridge into two 12' spans. The ridge will carry half the load of the rafters on each side of it, the eave walls will support the lower half of the rafters. So, the ridgebeam will support an area 12' long x 7' wide, 84 square feet. Assuming the weight of the materials is 10 psf + the 60 psf snow load = 70 lbs per square foot X 84 square feet=5880 lbs. Three 2x12's at 12' long would support this... easier than trusses in my book if you can handle the post all the way down.

ChugiakTinkerer

I think this is the part that Don P is referring to: http://countryplans.com/smf/index.php?topic=14235.msg191124#msg191124

And here is how the loft joists are tied to the rafters:



That is for a full loft.  In the timber frame cabin I will build someday I am looking at a partial loft and cathedral ceiling.  For that my options are a structural ridge or scissor trusses.  If I were on the highway system I would have trusses delivered to the job site, and maybe even unloaded on top of the walls.  For my application a ridge beam will be much easier to accomplish.
My cabin build thread: Alaskan remote 16x28 1.5 story


Peaceful Ambition

Wow! What a lot of good information, thank you guys, this gives me a lot to chew on for a while, guess I have some more research to do. I really like the idea of extending the joists to the eave, giving more headroom AND a nice overhang at the same time without comprimising the roof.

I suppose I'll do some more research on ridge beams as well. My statement about 'not being up for' it wasn't so much an unwillingness or laziness to try as it was a concern that either my wife and I wouldn't be able to lift a beam that size (didn't know you could split it), or more importantly, my concern that because I don't have much knowledge about load paths, etc, and I'm not hiring an engineer I didn't trust myself to try and get too creative outside the plans. But I DO have time before I get to that point to try and educate myself a bit more.

Could you recommend a good resource online or otherwise for reading a bit more about ridge beams? I have some framing books but they don't cover that in much depth.

I sincerely appreciate you guys taking time out of your day to help with our little project. [cool]


Edit: What is the name of that style where the end wall studs reach all the way up to the rafters instead of ending in a wall top plate?
You are not illiterate

ChugiakTinkerer

I don't know that the name strictly applies for those gable walls, but balloon framing is when the walls are built first and the second floor put in after.  The way I plan to build the loft is balloon framing.

it's nothing like a How-To manual, but the International Residential Code is the definitive resource on how to build a house according to code.  It takes a while to understand how it is all laid out but is a helpful reference on how to appropriately size joists and rafters, for example.  Where I am building there is no permit authority, so I can build whatever I choose.  It's important to me to ensure that the structure can withstand the forces that Mother Nature will throw at it, so I will be following code wherever I can.
My cabin build thread: Alaskan remote 16x28 1.5 story

Don_P

Full height framing is indeed called balloon framing as opposed to platform framing. The reason you would use balloon framing is to avoid having a weak hinge in a wall. The building code says that studs must run unbroken from points of lateral support. In other words from a floor plane to another floor plane, or from a floor to the roof. What the code doesn't delve into very well is that both the top and the bottom of that wall need to be well connected to the points of lateral support. People do a poor job tying the tops of those big walls to the roof pretty often.

Chapter 3 of the IRC, Building Planning, start here;
http://codes.iccsafe.org/app/book/content/2015-I-Codes/2015%20IRC%20HTML/Chapter%203.html
Notice R301.1.0-3
You can build prescriptively following the provisions in the codebook and as long as you follow those prescriptions you don't need an engineer to check it, we've done those things enough times the same way that we know they work pretty much anywhere. So that is what I mean when I say to build prescriptively whenever possible. The codebook then goes on to say that when you cannot build prescriptively you can look for a solution in several referenced standards and those are acceptable methods. Failing that, the parts of the building that cannote be built prescriptively need to be built according to accepted engineering practice.

That is the section where things such as minimum room areas are given, minimum sizes in baths, headroom, etc.

Chapter 8 is where you'll see the ridgebeam pop up;
http://codes.iccsafe.org/app/book/content/2015-I-Codes/2015%20IRC%20HTML/Chapter%208.html
Go to R802.3.1 "Where ceilg joists or rafter ties are not provided, the ridge formed by these rafters shall be supported by a wall or girder... That girder is also known as a ridge beam.

Go to table R802.5.1(8), (there's the rafter span tables that would cover you) scroll to the footnotes under the table. Notice the small table there, what it is saying is that the rafter tie cannot be raised more than 1/3 of roof height above the plate. (notice the next table is the connection requirements between the rafter and the joist to resist thrust.)

So in the cathedral area the roof is not tied, it then needs a girder, a ridgebeam, to support the rafters. It is pointing to an engineered solution for the cathedral ceiling. When I roughly sized the ridgebeam I was using accepted engineering practice... beam equations from the AWC and wood design data and methods from the NDS, see section R802.2

That's probably enough for one bite  :D

Peaceful Ambition

Don thanks for the link, that has been a great resource, TONS of info so I've been going through that, although the link seems to be a bit finicky for me.

Not much happeneing here yet unfortunately, the weather has been a big obstacle and this is probably the wettest winter, spring we have seen up here.
I did manage to get up and take a picture of what will be the build site, although not without getting my truck stuck in some SERIOUS soup along the way.





Our road seems to have multiple springs bubbling up so while some parts of the road are dry enough to be dusty, others are mucky as hell.

Luckily I know someone with a bulldozer who was able to get up and pull me out!  ;D
Until the road gets dry enough to get some concrete up here, I'm relegated to planning and research (which never hurts) although I was hoping to be started by now.

You are not illiterate


Peaceful Ambition

Holy smokes! The road is dry and we FINALLY got the contractor to come up and do the concrete!  :)
Now time to order some wood and get to work! Are solid beams gonna be the best idea for strength or would a home built glulam be just as dandy?

Here are some pictures of the piers/brackets, and I was a bit nervous after speaking with the contractor but I'd like to hear some input before i mention it to him.

First, there is no rebar in these footings, although they DO extend below the frostline (18'') they are 14'' x 24'' deep. He said we have very rocky and stable soil so it wasn't needed (I was away for work while it was poured so I found this out after...)

Secondly all of the Simpson strongties are lined up with each other very well (although some are not dead center on the pier), but some of them are mildly out of plumb, probably 1/4'' or less, do I just shim the posts somehow? Is that kind of common or should I be worried? Having a bit of anxiety about that. ???

Here are some pictures..







You are not illiterate

ChugiakTinkerer

I've built footings like this for the deck on my house, although I did use rebar.  The brackets being out of plumb aren't a big deal, as you can bend the steel to get it into vertical.  I would shim with pieces of asphalt shingle as needed.

I learned by reading this forum that a built-up beam is stronger than a solid wood beam of the same dimensions.  The beam load calculations established by the American Wood Council allow for a 15% increase in the design strength for the built up beam.   Be sure to locate joints over a post, that's the only way it is stronger.

The pier and post design is great at being low cost, but you sacrifice a lot of load bearing capacity as well as shear resistance compared to a continuous perimeter foundation.  You'll want to brace those posts and the beams too, to the extent that it seems like overkill.  But when you load up everything with the weight of a cabin,, especially if it's carrying a big snow load on the roof, it doesn't take a lot of lateral force to rack things over.
My cabin build thread: Alaskan remote 16x28 1.5 story

Peaceful Ambition

I'm not sure if I can bend the part of the steel that is out of plumb, I'm talking about the flat base of the bracket itself, but good to know asphalt shingle will work, and thanks for the info about built up beams! [cool]

When it comes to bracing the posts properly, the plans don't show how they physically connect to the beams, do I use a hanger of sorts or some kind of lag bolt to secure them?


You are not illiterate

Don_P

Hmmm, there might be a semantics thing going on here. To clarify, a built up beam is made of 2x lumber up on edge, good. A gluelam is factory laminated of lumber on the flat... don't attempt that, it will fail. Look in the codebook for beam and girder span tables for dimensions, I think you'll be in chapter 5.

If you build the girder in those pockets out of treated lumber and frame a stem wall on top that is sheathed in treated ply it would be better braced than putting the cabin up on poorly braced posts. Asphalt shingles are not shims nor is anything else compressible, I think code says 350 psi or greater but with the loadings this produces you may need better than that.

Peaceful Ambition

Well guys, feeling a bit bummed out today, not really sure how to proceed right now. :-[

I spoke with the contractor about the out of plumb anchors and he suggested shimming. Luckily I was able to find some composit shims that are up to 8000 psi. Started putting in posts and some of these anchors are actually 3/8'' out of plumb in either one or a combo of both directions. Got the 3 posts nailed in and leveled but they are basically floating, with only one corner touching the flat face of the anchor. This is obviously not ideal.

Should I try and just jam/hammer the shims in to fill the empty space as tight as possible? Cutting the wood at an opposing angle isn't working, the multiple angles needed to bring the post plumb are just too complex. I'm frustrated because this contractor is well known in our area and has built alot of local businesses around here so I dont see how they messed up this much and I'm not sure if I should try and ask them to fix it (somehow). ???

This house has been a dream for us for quite a while and the idea of starting literally off kilter is very disheartening and any advice on this part would be appreciated greatly.

Also, Don, my plan is to brace the posts thoroughly, I'm just not sure what kind of hardware I use to attach the pt 4x4 to the posts and joists.

Thanks for the help guys








You are not illiterate


OlJarhead

For starters I'd fire the contractor now before he messes anything else up!

You can shim etc and if needed later can go back and do something like I did (put in your own footing and surface bonded cement wall for a foundation after the fact) if you feel it isn't good enough.

If you are using posts and then beams remember that they will need bracing and lots of it.  I found that my cabin wasn't really 'stable' until it was very well braced and even then the addition of two foundation walls under it (I'm not done) made all the difference.

So fire the contractor (those footings look like a kid poured them, not a pro) and either hire someone who is professional (and therefore will do nice work -- meaning everything will be plumb, square etc and look nice too) or do it yourself :)

I know that sounds harsh but you want your cabin built right and I'd have NO confidence in that contractor now.

OlJarhead


To emphasize my point, I did this footing alone and I am not a professional.  It's 8" deep and 16" wide and level.  My point being that a pro (again, I am not a pro so expect better than me in a pro) makes things that are correct the first time and look good too.


This is something you can do yourself even after the cabin is completed (which is what I'm doing) but bear in mind that whether using the simple post and peer method or a foundation like this, that it is the most important part of the build!  It's the foundation, the thing everything sits on.  So do it right and you won't worry later ;)

Adam Roby

I'd have to agree, that work seems excessively sloppy for someone claiming to be a professional.

NathanS

A contractor without a license, or willing to lose it, by going around the code officials.

I don't think it's too late to dig out between the piers and then pour a continuous footing, or scrap the piers and offset the whole building a few feet and start over again - this would actually be faster and easier I think. Seems expensive now, but really in the scope of building a house it's not that much time or money.


flyingvan

#18
It would be so much easier to do the foundation correct now than to put all the work into a structure and come back and fix it later.   

   That soil looks awfully familiar---I built for my Mom outside of Lassen.  Similar dirt, similar slope.  You are going to build a rigid structure, attached to a flexible foundation, set in moving soil.  That dirt is creeping downhill---not fast, but it is.  It expands and contracts, too.  You have zero earth/wood contact separation---it's a great plan if you're into feeding termites.

   Your planned structure is small enough that hand building a continuous footing wouldn't be too hard.

   It's a beautiful property, by the way, and I see nice native building materials lying around everywhere.  Here's what I'd do--

1) Start with a retaining wall where you've cut into the hillside there.  Set up a french drain, pour a proper footing, and use the native stone for an attractive feature that redirects water away from your structure.

2) Dig a nice continuous perimeter footing, 24" deep.  Use plenty rebar and pour concrete.  After that you could use cinder block but I'm fond of slip forming smaller foundations.  Get at least 18" out of the dirt and provide for ventilation.  If you want, you can build a stemwall above that to provide under house access, good airflow, and somewhere for storage.

   A nice solid foundation will really pay off in the long run.  Take close note of OLJarhead's foundation, that's something you can do.  The retaining wall can be built as a practice run where it really won't matter as much... Finally I hope you know we all love building on this site and seeing structures go up---I learn something from every single build.  So when people are encouraging you to upgrade your foundation, we're really hoping you end up with a strong, safe structure
Find what you love and let it kill you.

Peaceful Ambition

Holy smokes! Thank you guys so much for your responses! This forum is amazing, i appreciate everyone taking time out of their day to help me out! Thanks guys! [cool]

So an update...after reading your suggestions I figured it'd probably be best to not ask the contractor to correct the problem since it may just make it worse and I called a carpenter friend to come and help me properly level and shim the posts, we got most of them done!  :D, and hopefully the next few will be done within a few days (my work schedule right now has me working 5-730 6 days a week so work is progressing slowly).

I put a LOT of consideration into just restarting the whole foundation, but as of right now money constraints as well as a strong desire to get the house weathered in by winter are going to make that unfeasable so I'm going to continue on. I'll  be heavily bracing the posts, and getting some simpson column caps, as well as going into this with the understanding that I will probably put in a stemwall within a year or two regardless of how the posts hold up. I know it will likely be more work than it would be now, but it's what I can afford.
Oljarhead your pictures were equal parts inspiring (for me) and maddening (that the contractor messed up so bad) so thank you for posting those, I really like visual aids.

A question, what would you recommend the minimum height be for the lowest post? I'm currently about 20 inches but I figure with that, plus an 8 inch girder and 8 inch joists that sucker is gonna be sitting pretty high and was curious how low I would be able to go?

@flyingvan I definitely think we will be doing a retaining wall at some point, it hadn't even occured to me until you mentioned it but I like the idea.

Once again thanks guys, I'll be updating with pictures a bit more regularly now that things are moving but like I said progress may be slow due to work. Stay tuned!  c*




You are not illiterate


OlJarhead

I found myself in the same place and did exactly that:  build it on the piers, go back in later and start building a better foundation.  So, if you have to do it that way you can.

For height some say a min of 18" ground to the bottom of the floor joists but for me I like 24" as that crawl space allows more room to do things like build that foundation ;) or put hardware cloth up to protect the insulation from mice and rats etc etc etc

jsahara24

Its my understanding if you are less than 18" from the ground to your wood it needs to be pressure treated. 

Peaceful Ambition

All the posts are PT, and yeah I suppose I'll leave em high for now to make my job easier in the future!

Just got done ordering some simpson column caps, holy MOLY those things are expensive! [shocked] Only ordered 6 (figured one every other column should be ok) and it came out to just over $400 after shipping!
They should be here in a week and then I can get those girders up! ;D
You are not illiterate

Don_P

The column caps do provide good connection, they provide zero lateral resistance just as the post bases provide good connection to the pier but provide zero lateral bracing. The taller the post is the longer the lever arm is who's overturning moment must be resisted when wind or shaking earth loads that post. This is not minor.

pmichelsen

Quote from: Peaceful Ambition on June 06, 2017, 11:19:09 PMAll the posts are PT, and yeah I suppose I'll leave em high for now to make my job easier in the future!

Make sure all of your cuts are treated, when time permits I like to soak all of my cut ends in a cup of wood preservative, obviously doing it this way requires some planning.