I've got a couple of books ( Ted Benson and Jack Sobin) and in the design stage of a woodshed/storage building.

My biggest lingering question is what size beams. My building will be 14 by 16 feet made up of three bents. The end wall bent will span 13 feet unless I put a post in the middle of it. Would 6x6 Hemlock be adequate? I'll be doing most of this myself and don't really have a good feeling for just how maneuverable a stack of fresh wet 7x7 or 8x8 beams will be. 6x6 seems manageable. Can one man move an 8x8 14 foot beam? I'll have a couple of other guys help when raising the bents.

The 13 foot span on the end walls would be acting more as a connecting girt I guess..less strength ok? I'm planning on a traditional roof, so as I see it the weight will be distributed to purlins to principal rafters to posts? So the top of the bent is really just a connecting girt and not a top plate where many rafters sit?

Am I even close on any of this???

One book by Sibin has a basic plan for a garden shed and he specs out 8x8 posts and beams for max spans 12 feet. This seems a little structurally excessive to me? But then his design has many rafters sitting on a top plate.

For my sill, I'm planning on making a "sand box" out of pressure treated wood, and filling it with small stone. The PT wood will be the sill. Since this will primarily be a wood shed, I'm only going to put a wall of vertical boards on the back side, and leave the other sides open. No floor. Sound like this will work well?

A picture of my basic plan:



My Plan Photo

The first thing you should think about is rafter thrust. That's what the 13' tie beam is doing. It's the most critical part of your design. The size of the beam is not as critical as the strenght of the joint where it meets the post. If the beam is bigger, the tenon is bigger, and thus stronger.

But perhaps you should consider modifying your design to change the tension joint into a compression joint. The easiest way to do that is to raise the tie beam so the rafter lands on it, rather than on the post top. CB.

Same here. It looks like the design depicted came from a Benson influence. Here is a look at a traditional english tying joint Clark eludes to.

http://www.tfguild.org/joinery/part2.pdf

6x6, imo, are too small, mostly due to not much room for joinery. 7x's would be about the limit from my perspective. If you have two connectors coming together at the same point on a 6x6 post, it leaves less than a 3 inch tenon and no room for square rule housing. And much less wood around the joint for the strength I would want to see.

Tim

Thanks Guys. Since I lack the expereince of dealing with 8x8 beams...can one man maneuver a 10 foot 8x8? I'll have some help to raise the bents but I'll be cutting the joints myself.

You can handle a 10' 8x8. I would guess it would weigh around 250-300 lbs. It would be a strain to carry it by yourself. Just lift one end at a time (with the fulcrum located in a couple of feet from the ends). If you need to go a distance with it, put it on a dolly or cart of some sort.

Plan on making yourself a timber cart for moving timbers around.

Here is one a customer of mine made:



Here is one that I made, but it wasn't the best design. His worked a lot better than mine did:



I went to the hardware store and got two wheel barrow wheels and a piece of all thread to make the axle.

Good luck with your project.

To move timbers around you can use a stationary roller.
Like this:



You pick up one end or pivot one end up and put it on the roller, then slide it where the timber balances on the center point and then you can rotate it some to set it off onto your saw horses.

Here we were moving 7x10's 22' long with just a sawhorse roller and another roller mounded to a short plank:



As mentioned use a fulcrum and balance points to move timbers.

Jim Rogers

Excellent. I missed this entirely. That tying joint deserved much more thought on my part. Initially thought I could simply my work by separating the tie joint and rafter connection. It would be simpler to just make a truss by putting the rafter on the tie plate, rather than all the fuss involved to reinforce the tying joint with fancy joinery and additional bracing.

Thanks guys.

One more question. I'm planning on using pressure treated wood for the sills, and putting the sills on a bed of gravel. The building it self will have no floor. I don't have too much faith in PT wood, but other than raising it all up on blocks or sonotubes this is the best I could come up with. Sound suitable? Since this is primarily an open wood shed, the sills and post bottoms will be exposed to the weather.

I think the point loads on a 2x sill will cause it to sink in the corners. How about white oak sills?

I was thinking 8x8 pressure treated sills. White Oak isn't too common around here. White pine and hemlock.

Ouch. My first source for 8x8 PT is $100 for a single 8x8 by 16 piece? I hate paying that much for what always seems like the junkiest southern pine.

If I understand correctly, the building won't have a floor, and the post bottoms and sills (if you have them) will be exposed to the weather. Why do you need the sills at all? Why not just pour a little concrete in sonotubes, and connect your posts to the concrete with some of those simpson post bases that drain? I can't recall whether you had 6 or 8 posts in your shed, but it seems to me that it would be real simple to pour these and make yourself a solid footing/foundation.

That is correct, the building won't have a floor, this is really a woodshed/storage shed. I'll have six posts and they will be exposed to weather. Could I use a connecting girt a couple of inches above the bottom of each bent instead of a sill?

I think what I'm kind of getting at is making this structure look like the other old buildings on the property (my barn and house). My barn just sits on some fieldstone. If at all possible, I'd like to avoid the sonotube/ galvinized post bases, though they would be a pragmatic solution. My initial thought would be to put down a bed of gravel, then the PT 6x6 or 8x8 sills. However, $500 for just the sill alone is a little steep for my woodshed. I'd love to find a more cost effective, yet visually attractive alternative. 6x6 PT is considerably less expensive, but then a 8x8 post on top of a 6x6 sill?

I like the the sauna tube idea the best(cheap and fast). Have them (6) come up 6" above grade and anchor your 6x6 p/t sill plate to the top. Also you will need a mid-height girt for a nailer at least. A 6x6 frame with 6x8 ties with though(or extended) tenons should hold things together just fine. Sounds like a great beginner project to learn from.
Thane

Just had another look at your sketch.
The Tie beams are on the ends... not the sides.
Put the plate on top of your posts at least 6" above the Ties.
a 4x6 rafter on 36" centers should be fine.
Dog the rafters in the plate and extend them to form an eave.
Hope this helps
Thane

6x6's will work for joinery if you use through tenons. I don't like using them in horizontal applications though for aesthetic reasons, and you don't have to go very far at all to create structural reasons. For example the 14' ties should be 6x8's at least.

skip the concrete, use something that will last. Granite blocks, you are in NH after all, Swansons on 101A in Amherst has an "economy bird bath base" its a 10x10x10 granite block, we have them drill a hole in one side, then a matching hole in the bottom of our post. Drop a rod into the granite hole and your post on top of that and you can't knock it off the granite.... of course if you're raising bents this won't work, but if you assemble a piece at a time this works slick. Again, being a granite stater I imagine the "soil" you're putting it on is probably gravel anyway....

Hey Guys, thanks for all the good information. I'm learning a lot here. I'm going to use 8x8 for the main beams & posts.

One nagging question I have is what to do about the sill & footings. This building will be largely open, just a wall on the back with front & sides open. Primarily this will be used for stacking cordwood, park a small trailer under ect. Originally I thought I'd build a "sandbox" out of pressure treated 8x8 and fill with gravel. The 8x8 pt would be the sills and I'd build up from there. Now, I with a cost of $450 for sills alone I'm looking for an alternative. and having no sills will make getting in with a wheelbarrow of wood easier.

Should I get rid of the sills altogether? One issue is anchoring the posts. I'd rather not use the Sampson post anchors..not crazy about how they look.

My posts will be 9 feet tall, would 45 degree bracing alone be sufficient with the posts resting on sonotubes or granite blocks?

Something like this:




I realize that with just the bracing, just the pegs alone will be resisting an outward force on the posts. Still though, I don't see another way to do this.

Hey Paul,

That's a good lead. There's a Swenson's not too far from here and they have those "Bird bath bases" Reasonable price too. Funny that I live in a town where there's granite all over the place but I can't get any of it that's useful to me.

Question, what size hole & what are you using for rod? Are you bothering with Stainless? Ot just rebar.

If I use these granite blocks for footings, would that be enough to hold the posts in place, along with the cross bracing without a sill? I'm looking at 8 foot walls, 12 feet total height.

-jeff

I also highly recommend the Guild's Small Timber Frames book. It has plans for 14 small frames, including a woodshed. CB.

Jeff,

At 50 lb/ cubic foot green, your 8"x8"x10' Hemlock should weight about 225 lb. In my White Pine project I found big differences in weight from one piece to another.

I found a peavy was all I needed to "transport" pieces (as large as 8"x10"x18') from one place to another. Lifting these large pieces up to my work surface worked well with the teeter/totter (4' apart) technique previously mentioned.

I planned my work surface to be the same height as my sills and thus, was able to move assembled bents into position for raising rolling on short pieces of PVC pipe.

I was lucky for the bent (~875 lb) raising in that there was a nicely positioned tree to which I attached a chain hoist.

I had a neighbor, who pointedly observed that a partially raised bent looked a lot like an oversized mouse trap, periodically stop by and lend a hand. But, I think it's clear that with time, patience, planning, care, a modest 18x24 barn can be built and raised single handed.

Carl

PS
I'm having trouble visualizing your "foundation".
Looking at your drawing, don't forget knee braces at the middle posts

Thanks Carl,

My plans keep evolving as I learn more.

Currently, I'm not going to use a sill..just posts. I was thinking I like Paul Freeman's idea of granite blocks under the posts. The granite would have a hold drilled, then steel rod in the hole and a corresponding hole in the post base. I will also put sonotubes under the granite blocks and will not be visible.

Sounds like the weights are not bad as single timbers, whole bents? I may need a to borrow a tractor to raise the bents.

I've been studying joinery, and deciding if I want to put the connecting gurts on the post top to make a roof truss, or below the post top and use a through-tenon or wedged through tenon.

If I don't get going and order the wood I'll be out there in January working on this thing!

I also need to figure out pegs. I might cut down a small maple or oak and try to make a few.

-Jeff

-jeff

I understand the aesthethic reason to use a simple rod instead of something like a simpson post bracket. But it seems to me that uplift from a strong wind might blow an open shed off it's stone foundation. Am I thinking wrong?

Hi,

Maple -n- oak are not equivalent and you cannot use maple as peg stock mostly because it's structurally not suitable for such a function and also because, for related reasons, it splits relatively poorly and pegs should be riven not sawn. Better haul the chunks of straight grained oak out of your fire wood stack that have been drying for a few years.

Greetings,

Don Wagstaff

DKR, yes I imagine wind could lift the structure off the foundation. I'm not really worried about it. I live in a town full of 200 year old barns and houses all sitting on granite blocks. Frankly I don't know if I'm violating building codes or not with this. I'll mention it when I turn in my permit application.

Thanks Don,

I was not aware that Maple was not suitable. I've got plenty of oak already cut to 16 inch lengths though.

Whoa. Better not mention that foundation point. I made that mistake on a very similar project and regret my openness with bureaucratic functionaries to this day.

Don Wagstaff

It seems I can't post pix here as I don't have a web page or pictures in the "cloud".

If you'd like some photos of my recent project and have broadband send me an email at carlmill#acsu.buffalo.edu substituting @ for #.

You know if you shrunk it slightly, perhaps to 12x16 you might not even need to involve an inspector. In some towns in NH anything under 200SF doesn't need a permit.

Also, DKR brings up a good point, if you are exposed to wind you may need hold downs. However my experience has been you have to be very exposed, I've done a number of single pitch wood sheds (sort of like a bus stop) that one would think would flip right over very easily, they aren't even pinned, just resting on granite blocks and none of them have flipped over yet. They are also so rugged that I'm confident if they did it wouldn't be hard to just roll them back up on their feet with a tractor... but that's probably not exactly the assurance you're looking for!

But my point is to consider the exposure you have to wind. If you're in a typical NH site carved out of a wooded area you're probably not in need of tie downs. But if you're fortunate to have a million dollar view you probably get some pretty good weather!

Our little town is pretty relaxed when it comes to building permits and such. I'm speaking to the guys at the town hall this week and I'll bring it up.

Definitely not worried about the wind. We are really tucked in. There was that tornado that came though a couple of years ago though!

Perhaps I'm late piping in but...

Put me down for the Plate over the Connecting Girts - Make the Common Purlins continuous - And I'll put in a vote for the sills. All part of the cohesion and redundancy that are particularly important if your foundation is less than completely stable and might maybe heave a little. To have a building move as a unit is better than it if moves in subsections.

6" Granite curb (sold way wider than you'd guess) set into a rubble filled trench, with proper perimeter drainage makes for a stable and beautiful foundation for outbuildings but at $15 a running ft just for the curb, it's not cheap and more than you need for a woodshed.

There is a boneyard of broken dreams available for the picking up behind the Concord granite-works up at the quarry that might yield some big chunks to bed your shed on. It's a great source for both big rubble and little chips for shimming dry laid stone.

If you are yet to order your timber, remember that small scantlings (those less than 5X5) should be ordered FOHC - Not every area circle mill can or will do this, and it may well cost a bit more, but you don't want to frame anything with little sticks full of pith. It's unstable and checks heavily. Go in knowing what you want and why and you'll be treated fairly.

The tornado crossed my town also, (my road for that matter) and I may be in the neighborhood, I could maybe recommend sawmills or whatnot.

Jeff - Read that free for the picking.

Maybe buy something, ingratiate yourself and give them reason, then ask permission and directions on the way up to the pile.

This reminds me..... As I roam around town I see old houses coming down, the granite blocks under the sills are collected by the excavator man and then passed on the land scape people who use them for borders around little flower patches and such. I could sure find more enduring uses for them. I had to scrounge the chips in the local quarry.

Thanks Will,

"Free of heart centers" Didn't realize that should be specified! Thanks. I'm looking to order my wood from Red Mill Lumber in Casco Maine, I'll ask them.

TIMBEAL, I've got tons of granite around here. Lots on my property but it is all being used for something. A big barn up the street burned down a few years ago and all that remains is a celler hole of large (really large) granite blocks. I asked the people who live there what they are going to do with all the granite and they say it is useless..the fire was so hot it made all the granite brittle. If I had a way to move it I'd like to take some off their hands.

I guess I assumed you were in the Concord area when you mentioned being near Swenson's.

Here are a list of other mills - http://extension.unh.edu/forestry/sawmill/sawmill_dir_print.cfm