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Evan Showell
04-18-2004, 10:21 AM
Thinking of adding a post & beam sunroom (passive solar) to the house for a family room addition. Addition would be c. 24' x 30' - 36'. Remainder of house is traditional stick framed. Could go with stick framed addition, but I happen to like the look & feel of post & beam. Anybody got an idea as to a first order approximation of comparative cost post & beam vs. traditional stick built framing?

Also, construction costs will be reduced somewhat as I will do the sheetrocking and a neighbor who is a licensed electrician will do the wiring at very favorable rates.

Just as aside, I am told construction costs in my area figure at about $150.00/sq.ft.

P.S. I'll also do the flooring.

Thanks.

J. Wellington Wimpy
04-18-2004, 10:29 AM
Hmmm..

Not sure I follow your plans - thoughts - notions on a couple of areas. Why Sheetrock post and beam, would you not leave this exposed, or covered in pine for example..

Also, electrical may be done in conduit or flex (armoured cable) for P&B exposed. Traditional roughed in 14/2 wire in romex etc may not work here.

BTW, framed housing in my area is at about 70 - 80 CDN dollars per sq foot.

[ 04-18-2004, 10:30 AM: Message edited by: J. Wellington Wimpy ]

rbgarr
04-18-2004, 10:36 AM
You might consider contacting these folks. They are very supportive of DIY projects.

http://www.shelterinstitute.com/timberframes.htm

They show a cost for a precut, raised, closed in, and metalroofed 24' by 36' timberframe building at $60K, or $70/sq. ft.

[ 04-18-2004, 10:53 AM: Message edited by: rbgarr ]

Evan Showell
04-18-2004, 10:37 AM
Sheetrock because I'm thinking that any area not glazed -- and there will be lots of glazing, will need to be finished somehow on the interior. As I understand post and beam, there are big open spaces between the posts and beams that typically get filled in with something. I said sheetrock because it's the first thing that came to mind and it strikes me as being fairly economical. Open to other suggestions. And yes, did I say I lived in a high cost area of the country?

Know any Canadian timber framers who want to spend some time in northwestern N.J. and get paid in U.S. dollars?

Hughman
04-18-2004, 10:59 AM
I designed and built my post and beam house, a simple raised-post cape in hemlock. The basic structure is easy. The devil is in the details. Call me if you want to hear of my experience.

imported_Steven Bauer
04-18-2004, 12:10 PM
Hey Evan, Check out that Shelter Institute link. I took their 1 week post and beam class (the same one Hugh took) and then the next year built a post and beam garage/studio for a customer. They will precut their timbers and load them on a truck and bring then to you. They will erect the frame and even wrap the outside of it in Stress-skin panels and install the metal roofing. The panels are 6 inch thick (10" for the roof) foam with OSB bonded to one side and drywall bonded to the other side. They nail these to the outside of the frame with 10" spikes. They can engineer in the window openings in advance.

http://www.shelterinstitute.com/images/frame.jpg

http://www.shelterinstitute.com/images/021704_exterior.jpg

http://www.shelterinstitute.com/images/021704_door.jpg

Around here they might be thought a little expensive but they would be pretty competitive in your area.

There is still a lot of work to finish one of these setups. Installing all the windows and doors, wiring (some things are a little tricky here) and exterior trim and siding.
A few years after I built that garage/studio I finished off one of these setups from Shelter for a customer. It went pretty smoothly and the house came out great.

Steven

[ 04-18-2004, 12:12 PM: Message edited by: Steven Bauer ]

ahp
04-18-2004, 07:43 PM
Post and Beam does give a warm and fuzzy feeling, but put on my engineers hat and decide very quickly that it is a dumb way to waste wood. Modern stick built construction is actually much stronger.

The reason that the colonial builders used it was that it was quick and dirty, they had no sawmills, and lots of trees. To get a structural member, all they had to do was pick a tree trunk about the right size and flatten it on two or fours sides with a broad ax. Some of the old houses in my neighborhood in Massachusetts had timbers like this from the original construction.

Fitz
04-18-2004, 09:28 PM
Well, my Massachusetts timberframe is still standing (barely) after 300 years, so maybe those Old Colonists had some knowledge too.

Also, my house is the only house in about 5 square miles that doesn't need a sump pump this time of year!!

Also, how the hell did they get those BOULDERs to build my basement - I'm in a glacial lake, about 5 miles from a source of 5 foot diameter boulders!!

Don't cut the old timers shy on resourcefullness!!!

Jack Heinlen
04-18-2004, 09:52 PM
I've done a bit of this, and it's a fun way to build a structure, sort of like stepping back to the age when Lincoln Logs were a rainy afternoon's entertainment.

My only comment, from an aesthetic perspective so it's a matter of taste, I would steer clear of the systems of ready-made foam. They work okay, but I don't like the look of all the frame exposed inside. It's likely just what I'm used to, looking at old houses, but I think it's awkward. With so few sections needing filling with wall rather than glass I'd like a two by fill, with your choice outside and blueboard and plaster inside. Plaster is so much nicer than simple sheetrock. Plays hell on your wrists if you do it yourself.

[ 04-18-2004, 10:14 PM: Message edited by: Jack Heinlen ]

Sam F
04-19-2004, 09:13 AM
Yes Evan, Stressskin panels are the way to go. They nail on the outside of the frame with very long galvanized screw nails and if you plan the timber spacing correctly there’ll be very few seams that need taping. Since you get drywall, insulation and exterior sheathing to nail your siding to all at once, to it saves a bunch of work and has superior insulation values compared to a stud wall. Be sure to plan the wiring ahead of time and perhaps get panels with wiring channels built in. (something I didn't have sense enough to do!)

Winterpanel (http://www.winterpanel.com/panels.html) is a source you may want to consider.

http://www.imagestation.com/picture/sraid19/pb0177c2e828a1f67e75204cfcb49a442/fdc8d5ff.jpg

Placing the panels on a roof is a bit of a chore though! ;)

abe
04-19-2004, 11:28 AM
Evan, Cost of post and beam construction of homes run about 30% higher than stick built here in the northeast. But, if I were to build a passive solar sunroom, I would expect the costs to be comparable, i.e. one does not need the plumbing, heating, AC, full foundation and other high cost items.


Post and Beam does give a warm and fuzzy feeling, but put on my engineers hat and decide very quickly that it is a dumb way to waste wood. Modern stick built construction is actually much stronger ;) My wasted wood shop has managed to survive though another season of snow loads here in the north country. Putting on my engineers hat I will admit that I agree with modern building practices that favor dimensional lumber rafters as shown here. As far as the vertical structure is concerned, I will argue that we saved a few trees.

http://www.imagestation.com/picture/sraid11/pc2052d08b034096828988668551e5c6a/fe0bdd5a.jpg

abe

Jack Heinlen
04-19-2004, 11:38 AM
Evan,

Sam and I are just disagreeable.

For what I imagine you are up to I'd fill with frame walls. I just don't like the look of the miracle sheets. They look like 'miracle sheets', and I don't like to look at miracle sheets. You'll still have plenty of lovely exposed frame, and the rest will look right.

Jack

Alan D. Hyde
04-19-2004, 11:43 AM
You may be able to get high-quality timbers for a reasonable price from a local portable sawmill operator.

There are links to local woodmizer sawyers here:

www.woodmizer.com (http://www.woodmizer.com)

Properly done, a pegged and braced frame will be stronger than a stick-built (balloon frame) house. And you can use excellent local wood that might otherwise have been wasted.

Alan

[ 04-19-2004, 11:44 AM: Message edited by: Alan D. Hyde ]

Jack Heinlen
04-19-2004, 11:58 AM
Alan's point is well taken, but you want this done soon, and locally sawn timbers might be a bit wet to use this summer. Not that they have to be really dry, good frames can be made with recently sawn timbers, and to get a ten inch timber to ambient is a five year wait, but it's nice to let them dry a bit.

Could be wrong about all that, and maybe Abe will chime in with better dough.

Just an addendum. I don't even know what a native chestnut looks like. It's a tragedy that that tree was decimated by the blight. I've worked on old frames of chestnut, had a chesnut mantle over my woodstove, and that is a great wood to work. Almost as strong as oak, works like mahogany, lighter than oak. Many of the frames for our colonials were made of chestnut. It's a shame it is gone.

Alan D. Hyde
04-19-2004, 12:00 PM
You can build with green wood, but if you prefer dry, many portable sawmill operators have barns full of well-seasoned wood...

Alan

Sam F
04-19-2004, 12:01 PM
Originally posted by Jack Heinlen:
Evan,

Sam and I are just disagreeable...

...They look like 'miracle sheets', and I don't like to look at miracle sheets... Jack the "miracle sheets" aren't miraculous nor can you tell if they are even there. The stress-skin panels are applied outside the frame and short of cutting into one, there's no way to tell that it isn't a stud wall. The benefits are that one doesn't add a totally redundant non-structural stud wall to no purpose and at the cost of cutting yet more trees. Panels are bunch faster by far to erect. The down side is that it is very hard to put one up by yourself (been there done that).
Now if you want to be historically authentic… how about wattle and daub? :D

High C
04-19-2004, 12:01 PM
My home is post and beam/timber frame, and I love it. The only problem with mine is one that may be common to some others. In a desire to have massive, visible second floor joists (visible from below), the builder spaced them pretty far apart, too far for the thickness of the floor above. So it's like a noisy trampoline up there. The joists are plenty big and frequently spaced to bear the load, but the spans between then called for maybe 21/2 inches of flooring to provide adequate stiffness. I have less than enough.

Be sure that second floor system is plenty thick if your plan calls for widely spaced joists.

Jack Heinlen
04-19-2004, 12:11 PM
Sam,

It's a matter of taste.

I worked for five years with a fellow who'd perfected replicating the look of colonial construction. If you want stressed skin panels on roughly a hundred feet of wall, with all that means as far as fussing with the outside of the walls etc, have at it. I don't think it's what Evan is looking for. I always feel like I'm inside a cooler when in a timber frame built that way.

Jack

Sam F
04-19-2004, 12:35 PM
Originally posted by Jack Heinlen:
I always feel like I'm inside a cooler when in a timber frame built that way.

JackJack if I didn't tell you you'd never know. :D
And while taste goes a long way, it hasn't yet chopped any wood for me. R30 goes further with that chore! ;)

Jack Heinlen
04-19-2004, 12:47 PM
Your way is not how I'd build it, but I'm a stupid journeymen on my best days.

It's funny, odd, how language affects some. Stressed skin panels! Who wants to wake up with those around them every morning? tongue.gif :D

P.S. They, the way a building is built with them, really is ugly. ;)

Sam F
04-19-2004, 02:03 PM
Originally posted by Jack Heinlen:
P.S. They, the way a building is built with them, really is ugly. ;) So is wattle and daub :D

But seriously how could you tell the difference? Fewer popped drywall screws?

rbgarr
04-19-2004, 04:00 PM
Sam-

Jack doesn't like sheetrock, either. He'd do it with plastered walls between the timber frame members! :D

Sam F
04-19-2004, 04:20 PM
Originally posted by rbgarr:
Sam-

Jack doesn't like sheetrock, either. He'd do it with plastered walls between the timber frame members! :D He isn't the only one to dislike sheet rock but if you saw my sheet rock taped joints (shudder) you could imagine what a hash I'd make of hand troweled plaster! :eek: ("Nice... uh... plaster floor you got there Sam")

And that's why my wife does most of the sheet rock finishing. ;)

Sam F
04-19-2004, 04:27 PM
Originally posted by abe:
Evan, Cost of post and beam construction of homes run about 30% higher than stick built here in the northeast. But, if I were to build a passive solar sunroom, I would expect the costs to be comparable, i.e. one does not need the plumbing, heating, AC, full foundation and other high cost items….
…Putting on my engineers hat I will admit that I agree with modern building practices that favor dimensional lumber rafters as shown here. As far as the vertical structure is concerned, I will argue that we saved a few trees.

abeI can’t comment on the cost question as I did most of that myself. It’s probably accurate though.
Using my house as an example you could have save wood but as my roof is way over engineered it’s hard to say how big a difference it would have been had everything been sized appropriately (sanely).
It so happens that I have a talent in math… that talent involves getting the most basic calculations horribly wrong so here are the numbers to check:

My roof framing, as built, contains 231,936 cubic inches of timber. 8”X8” X 168” (14’) rafters and 6”X6” X 108” purlins (each somewhat less than 9’ actually). That’s for 10 rafters and 32 purlins.
If I’d built the roof out of 2X10’s (would they be big enough?) it would have worked out to 188,160 cubic inches. That’s figuring on 56 rafters spaced on 16” centers. Add the now necessary top plates over the timber ends to support the rafters plus a ridge board and I’d have used 212,352 cubic inches. The difference is 19,584 cubic inches or about 25 ½ 2”X4”X8’ boards. Viewed strictly on a cost basis the timbers cost $.25 per board foot (144 cubic inches). 2X4’s were about $.50 a board foot (if I remember correctly… 2X10s are naturally a good bit higher but I don’t remember what they were) so the cost of wood for the roof works out to:
Timber framed roof: $402.66 (edited: yep I got that wrong on the first try!)
Stick framed roof: $737.33 (edited: Yes I got that wrong too! Just pitiful! redface.gif )
On a cost basis it was a no brainer. As it turned out, the idiot assumption that it would be no big deal to raise all those pairs of 8X8X14’ timbers into position involved a serious lack of brains altogether :D . In terms of the sheer emotional wreckage caused, the extra money would have been well spent. FWIW in every old timber framed house I’ve ever seen the roof timbers were all small stuff like 5X5’s. Only in barns did they use the big timbers and not in all of them by any means. It makes sense. Timber framed bents can be raised mostly from the ground while roof rafters necessarily require aerial acrobatics that are not quite conducive to personal serenity.
Here’s what all the fun looked like:

http://www.imagestation.com/picture/sraid19/pcfc15e6e215569d41eeb3dd588fae27e/fdc8cb1c.jpg

[ 04-19-2004, 05:20 PM: Message edited by: Sam F ]

TimH
04-19-2004, 11:27 PM
some of the oldest structures in the world still surviving are of timber frame construction. In Scandinavia there are timber frame churches still standing from the 8th century. That is timber frame (no mechanical fastners), not "post and beam" ( uses mechanical fasteners). And timber frame construction actually uses LESS wood than stick building if you look closer. You had better get a new engineers hat. :rolleyes:


Originally posted by ahp:
Post and Beam does give a warm and fuzzy feeling, but put on my engineers hat and decide very quickly that it is a dumb way to waste wood. Modern stick built construction is actually much stronger.

The reason that the colonial builders used it was that it was quick and dirty, they had no sawmills, and lots of trees. To get a structural member, all they had to do was pick a tree trunk about the right size and flatten it on two or fours sides with a broad ax. Some of the old houses in my neighborhood in Massachusetts had timbers like this from the original construction.

Nicholas Carey
04-20-2004, 12:28 AM
Originally posted by Sam F:
Jack the "miracle sheets" aren't miraculous nor can you tell if they are even there. The stress-skin panels are applied outside the frame and short of cutting into one, there's no way to tell that it isn't a stud wall. The benefits are that one doesn't add a totally redundant non-structural stud wall to no purpose and at the cost of cutting yet more trees. Panels are bunch faster by far to erect. The down side is that it is very hard to put one up by yourself (been there done that).
Now if you want to be historically authentic… how about wattle and daub? :D Actually, Sam, "stress-skin panels" (SIPs in the trade—Structural Insulating Panels) are more structural than a balloon frame wall. You can build an entire structure with SIPs: walls, floors, roofs. A properly designed SIP can span as much as 24 feet and carry tremendous loads: a SIP with an 11-1/4 inch core set up for a transverse span of 24 feet is rated for a uniform load of 36 lbs/sq ft (1/3 of ultimate load, so a 3x safety factor). The deflection with that load is about 3/4 of an inch. Shorten the span to, say, 16 feet and you can load it to more than 100 lbs per square foot with the same deflection.

SIP-only structures stood up through the magnitude 7.2 Kobe, Japan quake a few years back...when the entire city was flattened.

The benefits to cladding a P+B structure with SIPS are, in no particular order:

(1) Energy efficiency (fewer holes in the skin)
(2) Less wood, and lower quality fiber, is used. SIPs are made from OSB/waferboard and often from recycled timber, and less resources overall.
(3) Much lower labor costs. A small rental crane and a crew of 3-4 guys can erect and completely close in a SIP structure in just a few days. The finish guys' work is reduced to: walls and floors are planer, plumb and square.
(4) strength/stiffness.

#3 above offsets the slightly higher material costs (bringing the overall cost in at par with balloon frame construction).

[ 04-20-2004, 12:32 AM: Message edited by: Nicholas Carey ]

Ron Williamson
04-20-2004, 06:25 AM
Nicolas
With a genuine SIP,you don't need a timber frame,hence the name.
R

Sam F
04-20-2004, 08:18 AM
Originally posted by Nicholas Carey:

Actually, Sam, "stress-skin panels" (SIPs in the trade—Structural Insulating Panels) are more structural than a balloon frame wall…
That’s right Nicholas! A friend of mine who is a builder (and good at math) told me that if we had a severe earthquake and my foundation collapsed – that foundation is by far the weakest link, but the building inspector wouldn’t let me build it stronger :rolleyes: – then the house would roll down hill but stay intact. I’m not sure I’d care what with all the furniture piled on top of me but I guess it’s nice to know.
Using the engineering strength tables for sizing timbers the weakest timber in my house is 100% over the requirement and the strongest is 500% over. Add the insulating panels and you have an insanely over engineered structure… which suits me just fine. :D

ahp
04-20-2004, 11:14 AM
TimH, tell me, what is the difference of stiffness between a beam with a square cross section and a rectangular section of the same sectional area, say 4 x4 vs 2 x 8? I will keep my hat.

I know my native New England well enough to know that there are a lot of cellar holes where old post and beam houses once were. The point is not that some survived, but that any survived. I have friends that own some of these survivors. They own a full time hobby.

Alan D. Hyde
04-20-2004, 11:37 AM
Sam, to measure amounts of wood used, the unit of quantity should be the board foot. A board foot is 12" x 12" x 1" or 144 cubic inches. Although some sellers like to price in "running feet" and other confusing measures, board feet is the best measure of value, along with, of course, the grade of the wood involved, which is worth checking out for yourself.

Sam, why wouldn't the building inspector let you build your foundation stronger?

Alan

Sam F
04-20-2004, 12:42 PM
Originally posted by Alan D. Hyde:
Sam, to measure amounts of wood used, the unit of quantity should be the board foot.Somewhere in that mess of math I posted I converted to board feet... Did I do so correctly? I for one wouldn’t bet on it! :D


Originally posted by Alan D. Hyde:
Sam, why wouldn't the building inspector let you build your foundation stronger?

AlanAlan,
Part of that was budgetary; I could have paid for forms and poured a steel reinforced concrete foundation. That would have put me way over budget but would have had the inspector's blessing. My preferred solution was to surface bond cinder blocks for a stronger DIY wall. The local inspector had never heard of such a thing and wouldn't allow it under any circumstances. So we ended up with a conventional cinder block basement... and it's not a bit stronger than it has to be. :(
It so happens that I knew a contractor trying to do the same thing at about that time. He actually built a sample section of wall, suspended it between supports and jumped up and down on it to prove to the inspector how strong it was… The inspector turned him down too! :rolleyes:
No doubt the inspector would have approved wattle and daub mud plastering though. (I hate to admit this but some years previously I'd visited Jamestown and had taken photos of how that was done... just in case. ;) )

[ 04-20-2004, 12:43 PM: Message edited by: Sam F ]

Nicholas Carey
04-20-2004, 03:38 PM
Originally posted by Ron Williamson:
Nicolas With a genuine SIP,you don't need a timber frame,hence the name.Err, isn't that what I was saying?

New Post & Beam buildings seem to get clad with SIPs for speed and energy efficiency. Engineered like a old make+break engine :D

TimH
04-20-2004, 03:54 PM
The formula varies depending where the load is concentrated at, but for the sake of argument a smal simple beam loaded at third points the formula is R=(PL)/BD^2
for large beams loaded at third points the formula is R=((0.75W+P)L)/BD^2
where:
R= modulus of rupture in lbs per sq inch
P= maximum load in pounds
L= maximum length between supports in inches
B= width of beam in inches
D=Depth of beam in inches

but I dont see your point. stick framed houses arent framed with horizontal 2X6's.

I will reply later with how much more wood is in a wall framed with 2X6 studs every 18" as opposed to a timber-framed wall. ;)


Originally posted by ahp:
TimH, tell me, what is the difference of stiffness between a beam with a square cross section and a rectangular section of the same sectional area, say 4 x4 vs 2 x 8? I will keep my hat.

I know my native New England well enough to know that there are a lot of cellar holes where old post and beam houses once were. The point is not that some survived, but that any survived. I have friends that own some of these survivors. They own a full time hobby.

raycon
04-22-2004, 02:28 PM
Sam F -- Is that a home made "gin pole" you got there? If so how did it work out for you?

I'm going to be building one shortly to assist in our raising.

Sam F
04-22-2004, 04:42 PM
Originally posted by raycon:
Sam F -- Is that a home made "gin pole" you got there? If so how did it work out for you?

I'm going to be building one shortly to assist in our raising.It's not a gin pole but a home made portable crane with an electric winch. It was capable of dead lifting 1,500 lbs and could safely roll around with a connecting girt and plug it in between bents or set a sill timber (about 400 lbs) on the foundation. It could be disassembled in a few minutes and fold up sort of like an umbrella to move it between floors. The wheels at the back (visible in the picture) are industrial casters so it could be steered. If you look closely you can see a taut line stretching toward the camera. That was to keep it from rolling off the building while we wrestled the rafter pair into place. There are also cleats screwed to the floor to act as stops ‘cause I believe in redundancy.
I’m in the center working the motor controller and gently lifting the rafters. The fellow on the right is holding one of the pipe clamps used to gain leverage. Those things were heavy and we needed all the help we could get! If I can find a better picture somewhere I'll scan it in and post it for you.

[ 04-22-2004, 04:44 PM: Message edited by: Sam F ]

raycon
04-22-2004, 05:22 PM
Sam if you have some pictures I'm definitely interested in seeing them.

Looks extremely light weight I'm curious how it resists the tipping moment CG (load relative to crane) or tied off(that is no counter balance)?
Is it your own design the umbrella feature makes it sound marketable...

Sam F
04-22-2004, 06:06 PM
Originally posted by raycon:
Sam if you have some pictures I'm definitely interested in seeing them.

Looks extremely light weight I'm curious how it resists the tipping moment CG (load relative to crane) or tied off(that is no counter balance)?
Is it your own design the umbrella feature makes it sound marketable...I'll root through some old photos tonight for you. I'm sure there's something that shows it better somewhere. If I can get the old scanner to work I’ll post it tomorrow. And yes it's my own design but no it's probably not marketable - unless thousands and thousands of people want to start building their own cranes :D Trust me - if I invented it there’s no way it could possibly have commercial potential!
It's much easier to hire one with greater capabilities.
But this one worked on my schedule and was cheap. Without it the house couldn't have been built. That photo shows the maximum frame raising crew of three people. One dumpy little guy in his thirties, another in his forties and one 70 something fellow. This wasn't exactly a bunch of power lifters!
A sizable fraction of the frame went up with only my wife's help and all the timbers were lifted up to the house site with just the two of us. I placed all the sill timbers alone. That was a good thing since my language deteriorated greatly in the process. :eek:

The crane is not all that light either - the winch probably weighs 150 lbs, but the secret to keeping it from tipping over is that the front wheels are directly below the lifting cable so it takes very little weight to keep it from falling over. For especially scary bits I made sure to tie the winch end to something but it never showed any inclination to… well… incline.

The Mark I model used PVC rollers to get around but that was a complete nuisance and it couldn’t be turned. After an accident with a wrongly sized chain hook that smashed several rollers (and a ladder!) I took the opportunity to upgrade it to something more tractable. It proved quite handy but following the forklift operator’s rule nothing was moved any great distance while lifted. Mostly timbers rested on the forward “skids” above the wheels and were lifted only when in nearly the correct position. The exceptions were the bents. They were assembled on the floor with their sill tennons just above their final positions. Then they were raised gradually while I gently pushed the crane forward to keep up with the arc that the upper edge described as they went up. It sounds kinda scary but nothing ever misbehaved.

[ 04-22-2004, 06:09 PM: Message edited by: Sam F ]

Alan D. Hyde
04-22-2004, 06:38 PM
I like it, Sam.

Well done.

It's surprising what can be done using simple machines, but the old farmers knew how. A twenty- or thirty- foot tripod (tree trunks) with a handy billy on it (or a modern-day version with a come-along) can do wonders.* Cheaply...

Alan

* the landsman's answer to sheer legs...