This is sort of based on the 20X 1.5 story plans..............with some additions and changes which I know I'll need profesional help to finish, ref the beams sizing

Like most projects I've drawn about 60 versions and T shape houses, but was worried about the roofing aspects being beyond my skills.

So I started with the basic idea that many have built with the central part with 14 ft walls - 1/2 loft and 1/2 Open to the ceiling 32 ft long

and extended both sides with 12 ft rooms rather than porches

Q- when you US chaps build using standard timbers

if you plan 20 ft wide for example do you cut all the timbers down and build the exterior to 20ft or do you build using the standard size and the exterior becomes an odd size ?

Any way back to the design

The plot is on a north facing slope with the view to the north too so a solar design would not work, 75 lbs snow load, so snow is an issue and expected in large quantities



10 ft full basement, containing a 32 x 24 garage and a 32 x 24 ft studio split circuit Pex in floor heating shallow insulated foundation

Not sure yet on the walls either full pored or ICF not sure yet need to see the prices.

Every house in the area has this, presumably due to the depth of snow and wanting the views as well

Being a brit I've pictured block supports in the basement to support the main beams, you guys probably have another method, drawn are 16ft 8" X 16" lvl beams

1 each for each wall and 1 under the center of the main floor.

As I'm mixing and maching the roof supports , Ive added in a ridge beam 8 x 16 supported by 3 off 8x8 posts with a 16ft spacing

Walls all 16"OC 2x6

roof rafters 2 x 10 on same OC.

The loft would be built as per plans with a set in ledger

the front section would had doubled 2X 8"  bolted and stressed and 4 x 4 king posts sat on that extending up to the ridge beam, mainly for decoration

Both bathrooms have space for a stacked washer and drier, but only 1 on suite bath with walk through closet in the master side.

Being that its mountain and snowy the entry is on the second floor with an enclosed glass porch, glass again through into the house to try and get some winter sunlight and warmth inside, the double barrier hopefully keeping the winter outside !

Inside hallway has stairs up to the loft bedroom /office kids play area - and down to the studio / TV room, there will be a door seperating the studio from the house, so that you could use the studio as seperate accomodation if required

The front porch will be built later and will be timber framed.

one issue is the snow and the garage doors,but I could not see a strong way of putting them in the rear and access would be more dificult due to the shape of the plot

but I may add porches to cover the doors.

Electric water /sewage is all to the rear to make plumbing easier, the hookups under the entry way, the board electrics all in the garage

here's a few pics of the google sketch up, whats wrong and where would you change or improve it ?

I have to run, but the one thing that jumped off the page at me was the location of the garage doors. Right under the lower edge of a roof where the snow will slide and fall and need to be removed, not to mention the possibility of sliding when the vehicle is outside there.

More later.

We cut lumber to fit the need. Dimensional lumber varies in length by about 1/2" unless it is "precision end trimmed", precut studs for instance.



This is a similar house structurally, its a little bigger at 42x50 and a full 2 stories. The center hall is 20' wide the wings are 15'. Our rafters are also breaking on the walls due to length. I ordered 20' stock for the section from the tall walls to eave, and 14'ers for the rafters from the tall wall to ridge. We set the garage door lvl's today.

This is the structural thinking; The tall walls are bearing a good bit of the roof above and the floor loads so there are 2 bearing lines in the basement directly under the tall walls and no center beam under the 20' central great room. We used open web floor trusses. To give clear room under the tall wall over the garage we had to use a steel beam, a hefty one (they actually nixed the posts so we are clearspanning over 25'). The center post under this beam is a whole lot better. In ours I'm putting a large lvl beam in the tall wall to carry the roof load so that the steel beam doesn't have to support it as well as the floors.
The left hand tall wall is supported over a wall in the basement, down to a strip footing under it.

The heavy timber trusses on top of the tall walls carry a ridgebeam on top of them. Rather than needing a huge beam to span 42' we have divided the span into shorter segments on top of the timber trusses.

Your extended porch requires a heavier frame than you are envisioning, the kingpost and tie are structural.

If you plan on doing the roof yourself, a high prow front is not for the timid at heights.

The ridgebeam is carrying half the width of the upper roof, the tall walls are carrying 1/4 of that load each. So each 16' beam span is carrying 11' of tributary width...16' x 11'=176 sf. snow load+ typical dead load= 85 pounds per square foot. 176sf x 85 psf= 14875 lbs
Using this calc;http://www.windyhilllogworks.com/Calcs/beamcalc.htm
and inputs for #1 Douglasfir beams,,, Fb1300, E 1.6, Fv 170 an 8x16 passed for me.

The basement beams are supporting halfway to the ridge and halfway to the eave, plus the loft, plus half and half of the main level like the roof.
roof trib- 6'+11'= 17'x16'spanx85psf =23120 lbs
loft trib- 11'x16'= 176 sf x 40 psf = 7040 lbs
main trib 6'+11'= 17'x16'x50psf = 13600 lbs
total load= 30160 lbs... a triple 18" deep lvl or a 4 ply 18" deep worked for me, supplier can engineer this.

I would extend the ridge out for the porch and build a timberframe to carry the roof.

Edit;
I was sending some pics from today to the homies, thought this one might be of interest.
Looking in through the 16' wide garage door. We got most of the ice out and set the triple 18" deep lvl garage door header today, you can just see the beam pockets in the precast foundation walls. The steel beam is in place that is under the near tall wall with the open web joists and subfloor from there back onto the wall under the other tall wall. Tomorrow we'll set the joists from the header over to the steel beam and finish the floor (hey, a guy can dream big
) This room is 27' wide outside dimension and then the right side has joists running perpendicular onto the righthand wall, that part is different than yours.

Glad to see my beam cals were ok on the ridge-

I had wondered on the garage beam so I'll need to check into whats available, thanks alot for that info as I couldnot workout that load path, now its done its straight forward but when searching it was dificult to find.

OK middle beam not required under the floor, there's going to be a stud wall there anyway so I wondered about that.

mmm 16 inch deep , ok need to re-look at that for clearance  in the garage. ,



Yes the snow is an issue above the garage, I might add a long porch the other way to cover and spread the snow,I'll sketch it up an see what it looks like

the reason for this orientation you'l see from below

The land has a anchor pin for the house, its not where I'd like it..........the land is long across the mountain and not very thick

The entrance is set in stone too as its the only location in line with the road way from the front is a 20 ft drop off and to the rear at the pin end is 15 ft lower than the road and has a drop down to a drainage ditch.

The anchor pin is the pain, or I 'd move the house up to closer to the entrance and have the garage entry on the rear. and the toys parked behind the house where they can't be seen from the entrance



the red pin the issue with the plot

Whooops! just spotted a big error in my math, I didn't sum in the main floor load, look above and add them up yourself... total load on the floor beams is 43760 lbs
With a center bearing under the main floor the main floor tributary load contribution is 9200 lbs rather than 13,600 lbs for a total on the floor beam under the tall wall of 39360 lbs. Just checking quickly. I'm into a 4 ply 18" deep lvl. It sounds like you might be geting into a steel beam solution as well. This one was designed and built by a company called Metwood.

Is that calc for full span ?

as I have center posts both in the studio and the garage under both those below wall beams
center is 18" long  x 8" wide concrete block post ( dense concrete block not hollow)

I can work arround a post when opening a car door !

max freespan 13 ft

Those metwood look interesting , but the span tables are for linear LBS so I presume total load divided by length-----will give me 1230 lb per foot ?

L480 for least deflection on the table gives me a selection of beams for a 13 ft span ..........or have I missed something ?

But if I wanted to clear span 24 across, the side beam supports can easily be brought out a tad

from the metwood load tables 3 off 14 X 3 1/4" wil give me 1527 lbs per foot

http://www.metwood.com/pdf/allloadcharts.pdf

Now in my design the joists join directly to the beam and looks like yours do to ? how did you connect your joist hangers or you order with installed ? ( ie welded on )

Let's do it for pounds per lineal foot bearing on the beam
Roof trib- 6'+11' x 85 psf      = 1445 pound per lineal foot
Loft trib- 11' X 40 psf          = 440 plf
Main floor trib- 6'+11'X50 psf= 850 plf
Total pounds per lineal foot  = 2735 plf

Checking,
Your method should be correct but the number is wrong;
Total load 43760 lbs (from my whoops post this morning)
divide 43760/16'(the span I was calculating for)=2735 plf... matches the calc above
Total load on 13 feet of beam... 13 feet X 2735 pounds per foot = 35,555 lbs
Make sense?

The design values for a typical no fluff LVL is Fb 2900, E 2.0, Fv 290 (compare those to the values above for douglas fir, a strong wood)
I'm just blowing out on a 4 ply 14" lvl using those design values

There is another check in some beam's published data.
This beam has a maximum bending moment of 57,777 Ft-Lbs
The LVL beam data lists a max moment for a 14" lvl is 13,581 ft-lbs per ply... 13581x 4 plys=54324 max allowable moment, just fails

Max moment for a 16" is 17,477 ft lbs...x4= 69908 ft-lbs... This Checks

I'd make this column more than 8" thick, or I was envisioning a steel column. If you lose the post it will come down. It is cheaper to destroy the car around an immovable column.

This is a shot from the greatroom looking across the steel beam and the far end of the floor trusses bears on the outer wall and the triple 18" x 16' garage door header. (remember it has a much lower tributary load than the inner beams)

The trusses are 16" deep, the steel beam is 14" deep but is recessed below the trusses enough to allow 2 top chords of the truss to bear on it. So the trusses sit 3" over the beam. This is called a top hung truss end. The far end on the wall is bearing on the bottom of the 16" deep truss. In this particular configuration our steel beam is projecting beneath the ceiling 4", not too bad. Don't forget enhanced fire codes come into play with the garage.

OK still confused !

so how do you get from here

"Total load on 13 feet of beam... 13 feet X 2735 pounds per foot = 35,555 lbs"

to this ?

"This beam has a maximum bending moment of 57,777 Ft-Lbs" ?



so the bigger we get the more stress and strain on those 2 beams..........

so If I add a 3 more beams beams length wise and change the orientation of the joists to two rows of 16ft I beams I will remove this

Main floor trib- 6'+11'X50 psf= 850 plf


and be left with 1885 plf for the main beams, spreading this load arround should help with integrity down the line too

like this



Then just need to calc those beams using the 850 plf ? or another calc is required.

still confused

Might have been too much information, but this is how you figure the maximum bending moment on a uniformly loaded beam;
A rod hanging out of a wall 1' with a 10 lb load on the end has a bending moment of 10 ft-lbs
If the rod were 10 ft long with a 10 lb load the bending moment (torque) would be 100 ft-lbs
Going to a simply supported beam, a beam spanning onto 2 posts the formula becomes;
WL/8
W=load-35555 lbs
L=span-13 feet
So, (35555 x 13)/8= 57,777 ft-lbs
To show how that works on another problem, at 16' the max moment=
16'x2735 plf=43760lbs
(43760 x 16')/8=87,520ft-lbs of bending force to be resisted, notice how the bending force amplifies rapidly whith increased span.

In that check what we are calculating the maximum bending moment. Then it is compared to is the ability of the material to resist a failure by bending and tearing at the bottom in the center of span. Support a popsicle stick on two supports and push down on the middle and watch how the bottom "extreme fiber" tears and then fails. That is a bending failure. So when you figure a beam, the max moment is calculated then an adequate beam size of a material with sufficient strength is found to resist that bending force.

Notice also how much deflection occured before the failure, this is often the limiting factor so we need to check deflection also.

Gotta run for now, but this will give you something to mull over.

Don mulled over !

your help is much appreciated, I'll owe you a beer or too for sure

So my original design did not really spread the load around, this can cause issues even when engineered as stresses are localized to smaller areas, tolerances become more finite and small errors can cause issues down the road.

Ie one pillar taking thousands of pounds rather than multiple pillars all sharing the strain, a bit like a framed wall
Snow is not really predictable either !

so I've changed the structure a little in a similar way to the house you pictured.
I was going to add some proud wood work anyway to make it look more timber framed.

So added 3 beams length wise and changed the joists to all run 16ft front to rear so that removes some if not all of the main floor weight from the two loaded beams ?

If I add two more 8" beams above the high walls, I add 3 more load sharing points per wall and take some of the roof load off the garage beam too, with posts again at the 16 ft mark going straight down to the concrete in the basement

So does that just leave the loft weight and framed wall deadweight on those beams ?

And the wife and I get proud pillars and beams, just right for some black simpson architectural plates

Plus a single roof plane to make roofing easier...........I think this will be House version 56.6



just as a note this property is just arround the corner and he has the same orientation issue and snow in front of the garage !

Can I ask what software you are using to generate your construction views?  Thx!

Dave, both of us are using Google sketchup, a free CAD program that is quite good and relatively easy to learn to use. John, if you're following this, being able to post skp files might be something to think about for collaborative efforts.

UK,
I ordered 2- 24" deepx28' long LVL's today that will be used in the tall wall over the steel beam to take the 2nd floor and roof loads around the steel basement beam. Sounds like we are thinking similarly there. My tall walls are going to be platform framed so I'm putting the lvl's on top of the main floor's 9' walls and using them as the second floor rim and as roof support. Basically this was an oops on the part of the steel beam supplier. I walked him through the design twice and gave him my loads but the porch light must not have been on, he missed part of the load in sizing the steel beam. I'm catching some of it up top and redirecting it around. This is costing about a grand but we are picking up some redundancy in the beamwork... I don't really mind having an alternate load path in that area.

Yes your main floor loads are now on the left/right beams, the loft loads are on the front to rear floor beams and the roof loads are on the front to rear upper beams. There are posts or support walls in the basement under all the posts above. I'll let you take a whirl at the beams but would be happy to walk through more if you get stuck. Do sketch in the loft if you need help.

56.6? I think I have waaay more hours in our design than the architect who drew the pretty concept plans. Just counted, 63 existing versions/revisions to date, wow! Electrons are lots cheaper than lumber though  .

OK beams calcs going well, thank you very much for explaining it !

basicly now using the wood frame type construction the beam that worried me now basicly does nothing from what I can see


I've been quiet as been reviewing the design ref the snow comments,

where's that nicely curving snow pic saw it and then could not find it again ? comming off a roof and neatly folded back and forwards

By changing the roof I get a bedroom as well as a loft play room .............

but now I'm lost again -this time on the roof, the front I'll leave in the beam as its a feature in the big room,

and I'll run the upper joists along to the central post to match the other side

but for access to the peaked area the rear beam needs either shortening or removing.

What would be the best way of doing it ?

this roof will probably be contracted out, as the last roofing work I did was in dade county after hurricane andrew !


front view showing the roof

and below the rear view with the framing and beam that will need changing




as usual though changing a design by 1 point means you have to change other things too !

the bottom of the exterior steps will now become a large pile of snow !

Now there's a change 
A cruciform, or cross gable design. Lose the tall walls, work from a level 2nd floor deck if you can. There will be some custom rafter lengths but it drops to common lengths rapidly. LVL's both ways at the ridge, the valleys are also designed as beams, LVL's again... and count on them laying full of snow. We'll need to discuss how to figure tributary area in a valley roof if this is the plan, its a bit different than a simple gable to get the loads.
This isn't a great shot but you can see the same concept in the core of this house.


Just curious, have you played with layers in sketchup yet? It'll help to be able to switch on and off layers containing roof, 2nd floor, etc as you work on the design.

mmmm the electrons maybe cheaper, but they sure add to cost in the end !

I think I'll keep the roof as is,

Keep it simple stupid  KISS approach

and put a 12 ft wide porch above the garage doors V the other way arround.

yep the ridge will take some hits, I'll re-inforce it.

OK a few more weeks scribbling away with electrons, basic house size stays the same, probably sub out the exterior and framing to professionals as time will be limited.


Then I will do the interiors wiring and plumbing, size stays the same, ending up with 3 large bedrooms
no snow infront of the garages and I hope a relatively easy construction.

Working through the windows right now, designer view V's what will actuall fit and the framing dwgs in autocad......

Now my load paths are split everywhere, how would you do the beam  over the garage for example as its only going to see 1 floor of weight but two and a half floors of framing- no roof loads as will have a ridge beam.

This has been a fun project so far, even with the hours.

Very happy with the design and I think OK for resale as you could do each bedroom with a bath, american style rather than the UK 1 bath for the whole house !

artists impression !





Floor plans




Hours of electronic wood

Looks pretty straightforward structurally. The long garage girder would be sized to carry the main floor load. The concrete columns in the basement need to be sized to carry all imposed loads from above, I'd go steel with welded beam saddles.

The cross beams under the walls can probably be doubled joists, you'll need to check the ones under the dormer sidewalls above.

The tall support columns need to be checked for capacity and slenderness against buckling, no biggie.

I'd kick up the pitch on the shed roof over the stairs to mimic the porch roof pitch on the other side, it looks like it's getting mighty low in the windows.

Thanks for the input Don !

yes I'd stretched the standard plans too far from their original design, so I had a take a long look at my delete button and scrapped
a month of work.

Then I started afresh,using just the basement design and the rough interior, ech time I tried to put in stairs it messed with everything
so a straight gable became and T and then an X

The extra cost in the roof gives me two large usable rooms and usable loft space too.

I looked at this from the - invest in the size now, as adding structure will cost more down the road, and simply finish the interior as and when money come in.

All the utilities come in on the same side with two sewage stacks 1 each end of the house, the runway joing the two will be outside the pad ,for ease of maintenance in the future.

For the uprights I was wondering ? what would you commenly use in the US - mutiple 2x6's or what size timbers can you get ?

I'd drawn 8x8 posts which gave the interior a wood frame type look, but was not sure how to use them with the two floor construction, ie 2 short ones or 1 long one ?

the next up from that would be LVL's but I guess more expence.

rear porch windows are 9ft high "artists impression", these will sure shrink when i price them !

Presently I'm going arround the design changing out triangular windows for standard sizes, probably just have "picture" windows in the front.

I'm using  autocad for the dimensioned construction dwgs and a seperate word doc for detail dwgs cut and pasted from on line catalogues etc.

As I'll be giving this to a builder what sort of level of detail do I need to give them ?

I gave my first dwg set to an architect and he just gave it straight to a structural guy,so seeminly my hours of learning sketchup has paid off, with a working design.

On that note I would never have got to where I am now without the quality of the build threads and the information seen hereon the site.

Photos of framing , roofs and foundations all helped in taking this from ideas to paper- the next step will be finalising the autocad struture dwgs and getting a build permit !

Q when you apply for a permit as I understand it corridors and landings and garage - basement etc don't count as sq footage ?

How do you usually calculate it - V's cost of the permit !

QuoteFor the uprights I was wondering ? what would you commonly use in the US - mutiple 2x6's or what size timbers can you get ?

We can get just about any dimension, getting it dry is another matter but it can be found. Glulam is another option, stacked together 2x8's or whatever glued together and planed smooth, strong, dimensionally stable and look good.

QuoteI'd drawn 8x8 posts which gave the interior a wood frame type look, but was not sure how to use them with the two floor construction, ie 2 short ones or 1 long one ?

Your SE will take care of those kind of details, I'd go full height on the one in the GR wall and probably platform frame the loft edge, stacking 2 posts.

QuoteAs I'll be giving this to a builder what sort of level of detail do I need to give them ?

The more the better but also be ready to redraw if they have more input, the sooner you get them on board the better.

QuoteQ when you apply for a permit as I understand it corridors and landings and garage - basement etc don't count as sq footage ?

How do you usually calculate it - V's cost of the permit !

Each one seems to be different, basically they are trying to get an idea of the value and charge accordingly. I try not to volunteer more than is necessary.

Good luck, it sounds like you are moving right along!

Thanks Don roughly what I thought, I have a possible builder looking at my "dwg package Version 1" to get me some rough pricing done,

so I'm waiting for his questions.

and also from the HOA for a soil report they promised me, that the engineer needs.

I can see some unplaned bills appearing as I go forward !