Bernie’s bible, and “The Word” for a generation before and after, was Eric Sloane’s An Age of Barns, still one of the best ever written on timber-framing, mortised joints and pinning and pegging. Modern fasteners can be good, too, but it’s hard to beat the mortised, pegged joints used in so many antique barns that are still in service.
You can be a little site specific and flexible on how you build the proper foundation, but if you want your barn to be useful to your grandson, you start with the foundation and do it right, like Bernie is doing here. You probably won’t see any of the old barns that were optimistically built with an oak stump as part of the foundation because the oak rotted away, stressed the rest of the structure and the barn eventually went down. Build on bedrock, big boulders or a reinforced concrete foundation that goes below the frost line. It’s true: a wise man builds his house upon a rock.
What you do next depends somewhat on the site. Depending on your requirements, you can build a monolithic foundation (footer) and slab, or build a foundation and a low stem wall where the poured floor floats inside of it, on a sand bed.
As his was to be a part-earth-floored horse barn, Bernie did a little of both. Concrete may be OK and hygienic in a milking parlor, but it’s hard on stock to stand on concrete all day unless you keep it deep with bedding. Note the economical use of clean rubble stone to make the Red-E-Mix go farther on the slab. When the batching truck shows up, you want to be ready: solid and straight forms; any steel properly secured; forms and ground wet; screed boards ready; shovels, jitterbugs, floats and any other finishing tools at hand and tarps if it looks like rain.
This looks like Bernie asked for a good stiff mix, which makes stronger concrete. Any water in the concrete not necessary for hydration weakens the concrete when it eventually evaporates, leaving microscopic voids. To prevent larger voids and rock pockets in your pour, especially when using a rubble extender, you can’t beat a passel of family members in rubber boots systematically stomping through it. Concrete vibrators can also be rented and used for the purpose of eliminating the air pockets. Once the mix is poured, the mud is tamped all along the edge, especially in the corners, so the gravy flows into any rock pockets.
Now, this was a good driver! He not only worked one end of the screed board, but he gets in with a shovel! Once poured and tamped, the slab is screeded off with a long sawing motion while pulling the long side of the board toward the fresh material. Taking enough time in the back-and-forth part of this jiggles the mud and brings gravy to the surface, which you will need for a smooth surface. In many barns, the concrete is just screeded smooth and called good. For a better surface, you tamp the whole surface to drive any aggregate down. Then, when it just starts to set, you use a long wooden bull float to work it flat and even with no rock on top. Then, when it will support your weight on boards, you get on it with trowels and get it as slick as you want. In a barn, you probably don’t want a slick surface, so after it is troweled, gently pull across the surface with a stiff-bristle push broom, like you would do on a sidewalk for a striated texture.
Now, this was a utilitarian project, but Bernie faced the edges of the slab with flat stone for the aesthetic value of it. Note the J-bolts tapped into the concrete as soon as it has been screeded and set enough to hold them upright. Sills will be set over these, tying the structure to the slab or foundation.
The sills are measured and drilled to go over the threaded ends of the J-bolts that were cast into the edge of the concrete pour.
A good washer and nut firmly locks the sill (and thus the building) to the concrete. In green concrete, bring them up just snug. Come back in a year and give ’em all you’ve got!
Preventing lateral drift is important to keep upright members bearing perfectly on the sill. Here, Bernie drills a hole up into the bottom of the corner post for the insertion of a bottom index pin.
A corresponding hole is precisely drilled in the sill to accept the other end of the bottom index pin.
Post-and-beam construction gets a great deal of its strength from structural members being solidly joined through various notches, mortises or dadoes precisely accepting the other member and then being pinned in place. Even labor-intensive dovetails are used where appropriate.
A radial arm saw is hard to beat for precise angle cuts, large dado cuts and compound angles.
Mortised notches and dadoes can also be cut by hand, if you are off the grid.
Tight fits are essential, as even kiln-dried lumber is going to shrink some over the years.
This shot of the decked loft shows how gambrel roof rafters are joined with a birds-mouth cut that fits over the lateral purlins. Notice the bonus room this style has over a simple pitched roof—not just more space, but more usable space.
Barn and shed are framed in, ready for board-and-batten siding and roofing stringers.
Once it is sheathed, the structure becomes noticeably more rigid, and ready for the 1×4 roof stringers.
Not just a place to mount a weather vane, a cupola provides natural ventilation to keep an animal barn dry.
This shot shows the attention to detail that makes the difference. Note the birds-head cuts where gambrel rafters fit over the purlins, the inlet framing braces and horizontal members—even the care with which the siding boards are cut to fit around the rafter tails.
Here, Bernie installs an eye bolt for the block and fall that will bring hay to the loft. Larger barns usually had a trolley system to carry bundles or bales to the rear of the haymow. Tight, strong, winter-proof and user accepted—everything a barn should be!
Every homestead needs a wee barn. Even if it has nothing to do with animal husbandry, the efficient space and inherent strength of the traditional post-and-beam, gambrel-roofed barn will never go to waste. As a bonus, the basic design lends itself to cost-efficient, shedroofed add-ons, and many heritage gambrel-roofed barns have subsequently been rebuilt into homes, taking advantage of the extra usable space offered in the loft.
For both residential and utility buildings, the gambrel roof has been popular in America since the mid-1600s. The name comes from Norman English, and historians are still sorting out where it was first used. In addition to the more spacious top tier, advantages of a gambrel roof are that it tends to dump a snow load and individual rafter members can be fabricated from shorter lumber. Depending on the design, each rafter can comprise a vertical truss, offering a truss’ inherent strength. It is easily combined with dormers, as well.
Post And Beam
Post-and-beam construction has been popular for 1,000 years, and European buildings of this type have been preserved in continuous use since the Middle Ages because of their structural integrity and architectural charm. Across the U.S., it has been one of the commonest types of framing for a barn. Topped with a gambrel roof, it represents “classic” American barn architecture. It is a type of architecture that is appropriate for structures ranging from very small to very large.The deciding factors on a homestead often were purpose, available materials and crew.
The subject structure here is a horse barn built nearly 50 years ago by Bernie Powell, near Wilton, Connecticut. This barn’s an interesting piece of work as it was done right, and it reflects an interesting mix of time-proven architecture wrought with 20th-century tools, materials and techniques. Materials, and probably some building codes here and there, have evolved some since then, but because Bernie carefully recorded the progress as he worked, this makes a good textbook example of a basic structure that is adaptable to many uses. This barn was built as a utility building, but if you can see it sealed inside, with different doors and some dormers and calico curtains, that’s up to you.
Post-and-beam construction lends itself well to vertical board-and-batten sheathing, which, if properly nailed off, lends a great deal of load strength. Horizontal siding of various types can also be used, but this requires the insertion of studs or other nailers. Note how Bernie added a lower-elevation shed to his barn. Especially in a dairy barn, there is an advantage if you can always move hay, and shovel manure, downhill.
American Frontiersman 2014 Magazine, Issue #175: Take a look inside at the Table of Contents,...
by dennihu / Dec 24, 2013