I have been rethinking my cabin plan ideas, and am now leaning towards a 12x16 or a 16x16 with a loft area.
My main problem (other than money and the lack of land) is the time it takes to build. There is no way I can dry in within a single summer. I was originally thinking I could potentially build all of the framing with pressure treated lumber. Start off with a deck the first season, then a roof the second season, and finally close it all in on the 3rd season.
Then I got to wonder... other than wood that is in direct contact with the cement or very close to the ground, and if it is only conventional lumber (no plywood or OSB), would a non treated 2x hold up for 3 years in the rain without rotting or otherwise losing its strength?
If I were to build a structure without a floor, walls or roof, just all of the framing... would it hold up? Figure it does not have the plywood to keep things straight but at the same time it does not have plywood that acts like a sail with the wind, nor will any snow accumulate on the roof if there is no plywood up there. Would just the stick frame stand up over time allowing me the time I need to complete a build?
(https://i.imgur.com/F95ZtcS.png)
No, it will not hold up in most climates. Dry it in in one fell swoop. Build the foundation and stop. Then muster your resources and run for the roof. It's quite do-able :)
Hmmm... I just did some quick calculations and it would only cost an additional $297.14 to do it all in pressure treated. I am starting to see some light at the end of the tunnel. :)
I would beg my friends for help! You want to get a roof on and tyvek up in one summer season!
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I'm not real enthusiastic about your timeline. This frame above is a good start, I like the basic concept but there are some details I'd change. The main and loft floor girders cannot be hung on the sides of posts. They either need to be notched into posts, supported on jack framing or hung with hangers rated for the loads. The floor joists need rim joists to hold them upright and I'd install a row of blocking over the mid girder between joists to help them season as straight as possible.
The top plates need to be replaced by a beam as they will sag without studding. There needs to be some diagonal bracing, this is usually provided by sheathing, but if it's not there, bracing either permanent, or it could be temporary until future sheathing is installed, needs to be installed.
The gable end top plates create a hinge in those walls, there should be studs running uninterrupted from the loft floor to rafters. Studs should run from the lateral support created by the floor and roof diaphragms and should not be broken where there is no lateral support, it also makes the framing easier. The studs do not need to be installed at this point as long as there is diagonal bracing. I'd block between each rafter over the outer wall, leave that blocking 1 to 1.5" lower than the top edge for future ventilation.
Common nails subjected to cycling moisture are derated. Hot Dipped Galvanized ring shanks or spirals or Ardox nails will retain their strength and resist the corrosive effects better. Rather than a nail gun I'd use a palm nailer and hand drive nails.
I'm not crazy about surrounding your living area with copper naphthenate. Pressure treated lumber is pretty crappy, around here at least---seems they take the inferior pieces with lots of knots. Your place looks small enough to throw a tarp over
Our big boxes buy the cheapest treated they can. We do get some nice treated from one supplier locally, he specifies #1 when he orders and is the "go to" guy for treated. But, it doesn't thrill me either, our treated is ACQ but I'd rather not be the guinea pig. An alternative would be borate treated, that does leach out though, maybe a water repellant finish to slow that down and then the tarp. This is really small enough to be framed and dried in quite quickly. If time is the problem it might be better to sub out the shell.
FWIW, I managed to take our 16x30, from a bare but ready foundation to dried in without doors or windows in about 2 weeks. That was working from a pile of materials delivered to the site by the lumber dealer almost entirely by myself. But working virtually every day, one day after the other. Another week and I had the door and windows in and flashed, all walls and roof covered with building felt. In that space of time there was likely some time taken away to return to the city. I don't recall exactly how many. Mostly I was working. There was some rain that slowed a few afternoons.
I did spend time, a lot of it, planning. I used papers and pencils to draw everything and spent hours mentally assembling the components.
Thanks everyone for your feedback. I will be redoing the drawing and reconsidering the options.
Don_P - I would like to look into what hangers exist for the loft and main floor as well, I would not trust just attaching them on the sides like that. The main reason I wanted to have the 4x4 posts run from the pier to the roof was to help with stabilization so that the building does not fall off the piers. (The scissor effect thing). I will add blocking to the design as well, especially if I don't sheath the first season I need to keep the floor joists from bending and drying out of shape. The drawing has the bare minimum drawn in, but for sure all the walls will be studded before any sheathing goes on. (I wanted to get a frame in a standing position with only treated wood, but without costing a fortune). The top plates will have studding beneath then before any sheathing goes onto the walls or roof, to help support that load. I do need to consider some cross bracing however, especially if I want to put a roof or even tarp since that will mean a snow load as well as some wind resistance. I will add to the drawing with all of your recommended additions and redo the cost analysis.
flyingvan - I too am a little worried about this. I wonder how much this could leach into the living space... something to consider for sure.
MountainDon - I want to have every single measurement factored in to the 1/16 of an inch if possible way before the first piece of wood is cut. I too am a stickler for the details. SketchUp is a great tool to help with that.
Time line: Here are some very basic facts that contribute to the timeline problems. I have a 4 year old daughter, and my wife works weekends and evenings, so I am very much like a full time single father. I am with her 24/7/365. This limits my building in a very big way, but I would like her to enjoy "helping" me and being in the woods, I think it would be a good childhood memory for her to have. I also have 3 herniated discs in my lower back and am often in extreme pain. Some days are good, most are bad. I have been waiting for 16 months now for the "specialist" to decide if I will get surgery or injections, or something else to help with the pain. Because of this, I have to take it very easy. I may be able to dig 1 hole and fill it with cement in an entire weekend. I can't work 12 hours a day anymore, so I need to be as realistic with myself as possible, and plan it so that my timeline allows it to take years to complete. Friends are simply not reliable enough, nor do they follow my standards of building practices. (I am pretty finicky and want "perfection"). I do want a cabin, but mostly I want to be building a cabin. That is the fun part for me.
I hear you, I always assumed I would gracefully keel over mid furrow and they'd just hitch up another mule. Happily they don't dock you for damage on return :D. Obviously I like the continuous posts. I wouldn't notch a 4x4. A simpson HUC210-2 is good for 2680 lbs with a double 2x10 in DF/SP in souble 2x8 that same series is good for 2085 lbs, I haven't looked at your floor loads but that would probably get it. These are concealed hangers ( the ears turn inward so they could mount on the post face). A strap across from girder, across the post to the next girder would provide a good tie. The floor and wall sheathing will likely eventually do that as well. Go ahead and do the same thing under the top plate to carry the rafters, that will sag immediately under just the weight of the rafters with a double 2x4 flatways. This also takes the load off the floors and puts it onto the posts. The beams at each level then collect the load from each, the roof, the loft, and the main floors and deliver them to the posts independently rather than collecting the loads from 2 or more levels and delivering the accumulated load to the hangers on a level below. Essentially each level is bridging its' load over the level below to the support columns. Loads/spans/species/grade determine the member sizing, we can walk through all that if you need help.
By the time you get ready to close in the interior the treated will be quite dry, it'll accept a seal coat of paint to help isolate you from the treatment if it's a concern.
How do building departments/ inspectors look on extended timelines by home builders?
I am in much the same position, very limited availability to work on a cabin project, some minor health issues, and I can easily see my build going over several years. This is one of the main reasons I have not taken action to date in terms of submitting a plan for approval to my local building authorities. I just am not able to commit to finishing in six months (like I understand is the requirement in my home town), or a year.
I so much would like to be able to approach this at my own speed, not be under time pressure, but that does not seem to line up with the approval / inspection process in the US, at least as I understand it, where everything is geared to contractors getting the job done ASAP.
Thoughts on this?
It's probably unique to your jurisdiction. Here, I had three years from the time the building permit was approved---extensions weren't difficult to get but were expensive. I had two days to spare, most of the slowdown was due to weather. But really, the time between foundation and dry-in doesn't represent most of the build and shouldn't take too long
It is very much jurisdiction dependent. Some require extensions and charge mightily to keep things moving along, others don't care. I've gone on for 3 years on a large project with no extensions or problems. I had a helper have to pay another permit fee after 6 months, and everything in between. Always get an inspection at least once every 6 months to avoid abandonment and resubmittal for a permit. If that happens you'll be issued the new permit under the current code if it has changed, this can be a real problem. Talk to them and see how they handle it.
The last time I spoke to the local inspector about building code and time-lines he was pretty vague with the details - and he seemed to be pretty relaxed on the details, but I will definitely speak to him again when I have a plan in hand... if not before.
If it is OK to hang the girders from the posts (using the appropriate hardware), why is often said not to be OK to hang the floor joists from the girders using similar hardware? Most posts I see tell people to have the floor joists sit on top of the girders rather than using floor hangers attached to them.
You mean like this?
(http://4.bp.blogspot.com/_7UaKc2k_Heo/TJ4L7nJ_DWI/AAAAAAAABVA/fq8ZFJ4MtP4/s400/GEDC0906.JPG)
It is just about always better to stack wood on top of wood rather than using connectors to hang wood off of the side of wood. Sometimes, as in the case of the poorly braced pier posts, it is better to hang the girder off the side of a well braced tall post.
That said, joist hangers are fine for hanging joists most of the time. Where you can get into trouble is if there is a multi ply built up girder, which is generally the case. In that case the majority of the side load is carried by the first ply, significantly less by the next ply, significantly less than that by the third ply, and just about none by the 4th ply. With a built up girder and a side hung load nail them together very well. Ultimately a beam under a joist is more foolproof than a joist connected to the side of a beam by nails in shear. The connections in the first case are simply holding things together where in the second they are working.
The way you see most houses built on this site with a dropped girder (as opposed to a flush girder which is what you are asking about) I've commented and often wondered why people are doing it that way. The girder itself is laterally unrestrained, another unbraced hinge. In that situation dropping the joists into hangers on the side of the girder would help laterally restrain it, roll over protection.
Completely agree that stacking lumber is always preferable. I had to do this this way because AnnaMarie insisted on the wrap around porch, and the wildland/urban unterface rules forbade more than 14" of exposed joist bay area , so stacking was out. I had to 'T' all the beams in a herringbone pattern with a postcap at each junction; one of the beams didn't meet the 2/3 rule for cantilevers so had to pay for an engineers stamp there. Roll over protection---I figured I'd prevent roll over by weighing down the rim joists with a house.
I was glad to be able to take off about a foot of elevation for the house by doing this. The house was already taller than wide, I was bumping up against the height limit, and bridging to the porch would have been harder.
The only thing these unstacked TJI's support is the floor itself. Rim joists, beams, and squash blocks take the load
I am reconsidering laminating 3 2x4's together rather than using 4x4's for the main posts. If I did this, I would feel better about having sections removed to allow for the girders to be properly supported. Then I could also add some 3x7 Simpson fastener/ties to keep it all together.
Figure this would be a better solution? One advantage I see is that I could laminate 8' pieces, which are much easier to transport than the 16' pieces I wanted for the center posts.
(https://i.imgur.com/9KhXkUX.png)
If I were going to build like that (actually I have! lemme find some pictures) I would turn the three 2x4's 90 degrees and run the crossbeam through the center, and continue it along the length of the structure. Instead of going thick I'd go deep---like a 2x12 or14. This works out neat because you can slip the crossbeam between the two outer 2x's, get it dead-nuts on level, then cut the peice that supports it. You'd run carraige bolts through the whole mess, providing some diagonal support your current plan lacks
(http://bp2.blogger.com/_7UaKc2k_Heo/SBZlSPI2XDI/AAAAAAAAATA/mZwp4xCxkhI/s320/Carolina+008.jpg) That's my pavilion at home. At the AirOps station I built a similar thing---- except it was supposed to last one year until we got our hangar, and had to withstand 400 MPH winds. Having it blow apart in rotorwash into Lear Jets would be bad. That was 7 years ago; still no hangar.
(http://2.bp.blogspot.com/-eHE6H2SNNLo/T1tpmwJ8qSI/AAAAAAAABjE/O3lbUz0Gdmo/s320/Truckshelter.jpg)
My front porch is built this way too. I need a better close-up.
(http://4.bp.blogspot.com/_7UaKc2k_Heo/SZY_rbRqq8I/AAAAAAAAAwQ/1ol2XytuLUA/s1600/dangerboy1.JPG)
All this said, I've only used this for building lightweight outdoor structures. Someone esle with actual structural engineering background will have to tell you whether it's suitable for the increased deadloads associated with a habitable structure---but it's similar to pole construction so the numbers exist somewhere
Here's a little bit better picture. YOu can see how the rail is sandwiched between the studs. The rim joist below the decking is the same. I just stuck it in and blocked it to match the ledger against the house
(https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-prn2/t1.0-9/s403x403/1511063_10203601947675703_4346930688479077348_n.jpg)
I am just in the process of redoing my drawings, and as I am documenting it I am finding ways to optimize the cuts, and use as much of the wood as possible. I am looking for a good compromise between crawl space under the building and headroom inside the building. As it stands, I have about 2 feet of room under the floor joists to move around down there, and about 7' 6" of headroom inside (between finished main floor and floor beams of loft area).
1) Should I try to make more room under the building, or is 2 feet enough. I may one day want to add some plumbing (unlikely but possible), and I will probably want to insulate the floor from underneath at some point. At the same time, I don't want to be too high off the ground.
2) I think 7' 6" of headroom is more than ample, but would lowering that to 7' for example be very bad? Any thoughts?
7'-6" is minimum head room for habitable spaces in most American building codes. Play houses and cottages seen in old British movies are often lower.
In order for it to be even possible to build this alone in one summer, I decided to break it down into more manageable sections, and concentrate on each section one at a time.
This is the modified frame, using laminated 2x rather than 4x4 post. The girders are now on top of members, and everything is bolted together. I have hangers in place, but still need to add more supports and bracing. I will update this again once I am sure on the details.
First the piers with cost breakdown.
(https://i.imgur.com/PjqYI3x.jpg)
Whole Frame (bracing still missing - more for proof of concept)
(https://i.imgur.com/lMb3S5a.jpg)
In order to make this more doable, the plan is to break down the build into different phases. This phase is the basic structural phase, just the skeleton of the building with no sheathing. Then, this phase is further broken down into 4 quadrants per floor. The idea is that I can build just the front left lower quadrant and it will hold up by itself until another quadrant is attached to it. Once all 4 are done on the main floor, I move up to the second floor, and finally the roof.
Lower front left quadrant example
(https://i.imgur.com/Qk724jX.jpg)
Each section of each quadrant is then broken down into it's members, and a cost analysis is done which will be tallied up at the end. Every section and beam is glued and screwed together. Everything will be cut, end cuts treated, beams glued and screwed at home and just assembled on site. This should make things go faster, since I can work on the sections during the week in my garage with electricity. Once there I just bolt on or nail together whatever sections I made during the week.
Sample section with cost breakdown
(https://i.imgur.com/zwSp8PK.jpg)
If you think I am on the right track, I will continue like this until the entire cabin is sketched out and every last detail, nail and screw is accounted for. Then I will have a realistic idea of how much this will end up costing, and how much time I will need to complete it.
A lot of this is just based on pricing at my local Home Depot. I will likely look into how much it would be to get a trailer of concrete, rather than using 50 bags at 66 lbs each (talk about a lot of work). Anyways, this will likely change a lot over the next year, but if I am to break ground next summer I think it is important to get this discussed and planned as much as possible ahead of time. Thanks in advance for your comments... again, the bracing will be improved, and temporary pieced will be added to the drawings in due time.
How will you actually use this space? Where is the stair and the major fixtures and spaces - bathroom, kitchen, social area? How does it work with the site? I would suggest humanizing the building before getting too detailed with the structure.
quick thoughts, we need to run to Asheville and play with an experimental hazelnut sheller, woohoo :)
Flyingvan's approach is the way to go for building the columns, go to awc.org and read up on spaced columns in WSDD (wood structural design data), one of their free downloads. The beams and columns could be built ahead of time and would look like mortise and tennoned timberframe components. The beam ends have very low bending moment and the tennon needs to resist the shear at that point, quite do-able with the single ply at the tennon IMO. I'd much prefer to see 2x6's, the column capacities need to be looked at but a 2x6 has alot more meat.
Lose the top plate dividing the upper gable and creating a hinge, those studs should run continuous fron 2nd floor to roof.
If the pier to post connection were plates embedded in the post and deeply into the pier you could get rid of most of that rotation point and make that connection rigid.
Quote from: John Raabe on April 18, 2014, 11:23:19 PM
How will you actually use this space? Where is the stair and the major fixtures and spaces - bathroom, kitchen,
social area? How does it work with the site? I would suggest humanizing the building before getting too detailed
with the structure.
I laid out how I thought I would put everything in the previous design, but I did not want to post the pictures because it shows the old connection points, and I also added to the height of the loft area since the space looks terrible small up there, head bumping territory. I only had access to a few premade models, so I put in there some big beds, realistically I will likely have simply mattress or even blow up ones up there. I also drew in a toilet (my skills are still in progress with this tool) but it will likely be just a chemical toilet. I do see having a sink with some rain water collection to wash up, with a small grey water pit outside. The structure will be used primarily by myself and my 4 year old daughter. 90% will be day trips, I don't see us staying up more than one night at a time. It will be 95% summer use, I may go up alone now and then more to check out the site and make sure things are secure. The site is still in question as I have not yet purchased it. I came very close to a beautiful site last year and lost it in a bidding war because I was stuck at work in Montreal and they needed me in person in Malone NY.
(Please disregard the structural components in these, I am posting just for the layout reference)
(https://i.imgur.com/2qGa8gF.jpg)
(https://i.imgur.com/W2at4Wk.jpg)
Basically, I would have an 8'x8' section for bathroom/kitchen, an 8'x8' for a table, chairs, and door entry probably, 8'x8' for a sofa/lounge area, and 8'x8' for the ladder up, and possibly a small heating stove.
Quote from: Don_P on April 19, 2014, 05:41:18 AM
Flyingvan's approach is the way to go for building the columns...quite do-able with the single ply at the tennon IMO. I'd much prefer to see 2x6's...
Lose the top plate dividing the upper gable and creating a hinge, those studs should run continuous fron 2nd floor to roof.
If the pier to post connection were plates embedded in the post and deeply into the pier you could get rid of most of that rotation point and make that connection rigid.
Is this what you mean by the gable hinge? My idea here was the properly brace the top of the side wall because it will extend higher than 2', probably in the neighborhood of 3 1/2 feet. I was worried that it would want to separate, hence that peice in red.
(https://i.imgur.com/1wlQ1PZ.jpg)
Is my new design following Flyingvan's approach? That was my intent, so if I did it wrong again please let me know. I have been tossing back and forth between the 2x4 and 2x6 laminated beams. 2x6 is most definitely stronger, but then my ties to the piers need to change, and all my exterior walls need to go to 2x6 rather than 2x4. Since this will likely be used 95% of the time in the summer months, I did not think I really needed such a thick outter wall... but I am seriously rethinking this.
I am also not sure I understand the last part, the simpson carport saddles have rebar like bars that extend I think 12" down. I have never done any rebar work, so I am a bit confused as to how it needs to be used, when the pier is mostly underground I would assume it doesn't need as much? (Work in progress)
Thanks for the comments, these are extremely invaluable to me. Hopefully I can have a complete plan in hand the day I buy the land.
Yes the plates in red are the ones that need to go away. I understand and don't disagree that a tie there wouldn't hurt but most importantly there shouldn't be an unsupported hinge in the middle of a wall. The studs need to run from one point of lateral support (the floor diaphragm) to another point of lateral support (the roof diaphragm). If you want a tie a metal strap wrapped from one sidewall top plate, across the outside of the gable studs and around the other sidewall underneath the sheathing would provide that tie. That is actually unneccessary because the rafters hang from the ridgebeam, preventing any outward thrust on the sidewalls. The rafter load becomes vertical onto the sidewall. But the metal straps won't hurt a thing and would ultimately strengthen the structure. You can buy roll strap from Simpson... you could also buy some lumber band strapping off the roll at the building supply, non code but cheap and code doesn't enter into this. I cut the lumber bands on incoming bundles of material at the band clamp and keep some handy on the job for additional ties in places, trusses tend to come with awesome strap.
The posts and beams are not Flyingvan's method yet, I'll try to draw a detail and post it. You will need more rafters, I'm assuming you're just showing the plane at the moment.
BTW in sketchup you can draw one member, select it, then click the move icon, then click ctrl and drag a copy of a member to the next layout, then type x 12 or however many copies you want at that spacing and it'll copy that many rafters or whatever member in the model, makes drawing repetitive members quick.
The posts can be 2x6's and the wall studs could be 2x4, leaving the posts as a feature element inside, they could be left like that or later wrapped in a decorative trim if desired. Just another cost/benefit thought.
The Simpson pier brackets prevent uplift but have no lateral capacity, the connection of post to pier is a hinge. If the soil adequately braces the pier then all is well. The soil is an unknown and the piers are small. If the connection of post to pier is rigid the pier cannot rotate. I know people think sonotubes and self engineered piers lightly connected to posts are adequate to support a house but pay attention to the size of piers and the connections used in parking lots to hold up just light poles and signs.
I'm not an engineer and this is their territory. This is a better connection than the Simpson's. Something along these lines is much longer and more rigidly connected to the post. The moment they are giving is the resistance to hinging at that post to pier connection.
https://www.permacolumn.com/what-are-sturdi-wall-brackets
These show what I was thinking, I believe it is what flyingvan is showing.
(http://timbertoolbox.com/sketches/tennonedgirder.jpg)
(http://timbertoolbox.com/sketches/mortisedpost.jpg)
(http://timbertoolbox.com/sketches/builtuppf.jpg)
Yes!
WOW I like that. Sort of a large mortise and tenon joint that is so simple. This summer or fall planing a wood shed I might just have to try that.....
Hmmm... only down side I see to my design is that on mine each girder is being held up by 2 of the 3, whereas in this one it is just one of the three. I suppose you would also add a simpson support underneath the entire assembly.
I may go to 4pcs of 2x6, and make it a structural element. Keeping the 2x4 walls as Don mentioned, I think that would be a nice look. 4 2x6s should be more than ample, and then maybe I can do Flyingvan's approach but with 2 pieces going through. Need to rethink...
Don, yes, I plan on having a rafter every 16 inches, and all walls will be completely framed in also at 16" on center. The drawings here were partially drawn only... thanks for the Sketchup tips, I will work on the newest ideas this week.
I was not expecting there to be much of a hinge effect from the post to the pier mostly because the post can't hinge since it is supported all the way up. That said, I could be wrong... my nephew is taking a welding class (top of his class) and they have access to all kinds of metal and can build whatever they want as long as it's welding. I sent him that website and asked if he can build these. If so, I will ask him to do 9 of them, sized for 4x 2x6's, and 10" high, should be perfect. If he is allowed to do it, that will save me some $250 and give me all the support I need. (Maybe wishful thinking, but it can't hurt to ask).
Instead of going wider, go deeper. Like I pointed out before this will provide some sheer strength. (one 2x12 instead of two 2x8's for instance) When you run two carriage bolts through all three, it's supported by them all. I countersink the washer and nut and use a 4 1/2" bolt so nothing sticks out at all.
So you stand up two of your studs in the pier straps, don't worry about how tall they are. Put a scrap block between them and just hold them in place with a clamp; you can also run a diagonal through all your uprights just held in place with a temporary wood screw.
Then you just shove your floor beam through, between all the studs. You can get it exactly level, then cut the middle blocks for it to sit on. Re-check for plumb then run bolts through.(http://1.bp.blogspot.com/-yalQD3BmOME/U1WnZUiBXaI/AAAAAAAACHc/9YycQv0IFTU/s1600/IMG_0366.JPG)
(http://4.bp.blogspot.com/-uwIAvF6wcZ0/U1Woey8OiRI/AAAAAAAACHk/_15aMyC-LjU/s1600/IMG_0364.JPG)
(Went outside to take some pics of this---let me know if there's some angle or detail you need that I didn't get)
Thanks for taking those pictures, it does help to visualize it. The idea of using 4 would be to give it an almost square look (5.5" x 6") but looking at your pictures it looks nice like that as well.
I will do some more drawings this week, and see what works best for the overall plan.
You were concerned about the single ply at the beam ends. In a simply supported beam, a beam supported at 2 ends, the maximum bending force climbs toward the center and is very low at the ends. The shear is just the opposite and is highest at the ends... but I'd bet we are in range. This needs to be checked. for the beam I drew, a beam supported in the middle and at both ends the force is distributed a little differently. The center posts bears 5/8 of the beam load, the ends each bear 3/16 of the load... the force acting on those tennons just dropped a good bit from each carrying half the load.
The spaced column has close to the buckling and bending resistance of a solid 4.5" thick member where the post you were drawing has the buckling and bending resistance of a 1.5" column, much stronger.
Ah... I think I finally get it. While my other drawing may have had better weight load strength, it lacked lot in shear strength. I started a new drawing but got too busy at work. I will redo this with 2x6, and submit it for final inspection later this week. ;)
One more question... since this is a post and beam now, with all the weight being over the posts... that means the floor joists are only holding the weight of the floor and whatever is on it, so I can do way with having a girder underneath the floor joists right? Seems like it would make for an easier build, and give me more headroom inside.
It probably won't be the final drawing, but I think it's evolving into something good.
The bottom sketch in my post above, in my mind would have joists on hangers between those triple girders but they could also sit on those girders. There are some advantages to sitting up on the girder though, wiring and plumbing are potentially easier, it saves on the cost of hangers and it is stronger
I might go with joist hangers rather than the girder with rafters over top. If I go with girders, I need to add some end pieces, and I need to brace the joists to the girders. If I use hangers, my ends are already blocked and there is no additional bracing. If the floor was holding up more than just itself I would not consider this, but since it is not, then I think this is the way I may go.
I need to have the joist hangers attached to the beam that is being sandwiched. I decided to try using a single ply sandwiched on the side walls, and double beams sandwiched in the middle, so that each 8' section of floor is being supported by its own beam.
(https://i.imgur.com/20XRYhr.png)
Not sure how well this will translate through an image, but this would be the first floor (I would still add some blocking in the middles to help with stability and bending.
(https://i.imgur.com/uxwtYUA.png)
I also designed two pier-to-post brackets based on that website, and sent them to my nephew. He will check with his teacher to see if he is allowed to build them, and how much they will charge me for the raw material. If it is reasonable, I will go ahead and do it.
Oh, and these are 2x6 now. The light blue ones are the treated lumber, the whites are non treated. I will either build faster or tarp everything.
You could extend the outer two 2x's higher than the inner ones to form a cradle to support the girder---kind of opposite what I did for the porch. The middle 2x extends up 7 1/2" so my two 2x8's rest on the outer 2x's, making room for the diagonal supports. Everything got filled in between the two 2x's running horizontal, forming a 3 ply beam (held together with carriage bolts)
I am considering different possibilities for giving the posts some lateral support. Since the walls between the posts will not bare any weight, if I use something like this as a basic shape for each of the sections between the posts, modifying each for window and door framing, would this provide the lateral support I am looking for? The side 2x4's are spaced 2' from the edge on each edge, so the triangle on each corner is what I am hoping will provide that strength.
(https://i.imgur.com/zKuRxyL.jpg)
I could alternatively have one diagonal across the entire span, but then I can't add my window and door openings. This should still be relatively easy to insulate, just a few more cuts. I plan on using cedar strips/planks on the inside finish so I would also consider their spans for the framing, but essentially this would be the minimum I would have in each of the 8 sectional walls I need to build. Once the sheathing is on it will strengthen the entire thing up, but I was hoping something like this could work as well.
Sure this will work if there is enough and if your bracing cannot slip. Google "fachwerk" for some historical examples of this method of bracing.
I'm assuming I'm looking at 16" oc joists, 8' post grids, a 16'x16' building. It looks like in #2 or better SPF lumber, double 2x10's will work for girders, 2x6's will work for joists. There is room under the joists to nail a 2x4 ledger on the girder to support the joists rather than using joist hangers if you wish. This would also slightly stiffen the girders. If the center posts continue on up to the ridge, the same pocket scenario would make a good ridgebeam saddle.
If you are welding the post brackets, I would weld a strap across both open sides high and low. The low strap would be a bit off the bottom to allow a drainage slot. This would give a bit of lateral support in the other direction.
Heheh... I just emailed my nephew with this design and asked if it would cost less due to less metal. Very similar idea to what you just described.
(https://i.imgur.com/uYm2tJJ.png)
Need to put the kid to bed, will reply to the rest later.
Why not continue with sandwiching stuff for your lateral support? If that wall you show has no door, you could run something corner to corner, between the left and right posts. Or if you need the opening, run a few more verticals then zigzag them either side.