Fire Tower

Dirty Little Secrets

2009-12-03T09:38:00.000-08:00

There are, actually, quite a few DLS's involved in timber framed homes. Many of them are revealed while trimming and outfitting the building. Others, during the timber seasoning phase. A few only crop up with usage. One of my favorites, though, is The Huge Budget Bump for Christmas Trees. Timber framed homes, of course, are not the only homes with tall great rooms. But a tall great room with celebrated timbers seems somehow to accentuate the primordial lust for a wicked big tree. This example was sent by a favorite client, John McRae, showing the 2009 edition installed in his beloved NH home - The Beeches.

Based on my own decades of installing significant trees in a lovely timber framed great room, I offer the following advice and tips:

I have had luck, going to funky cut-em-yourself places and offering to harvest one of their left over monsters. Some tree growers are happy to have a tree removed that has already outgrown their more standard market. Make em an offer, see what they say.
I love hanging trees from their upper limbs or trunk, rather than relying on nearly inevitably overwhelmed tree stands on the floor. You can use a noose or a pair of sticks, wired together under convenient branches. The sticks, then, bridged between two handy timbers in the frame (and I would carve the date, height, and price of each tree in the reused sticks) This also allows for bigger green-sustaining water buckets. Speaking of which, look for those siphon fed buckets - much tidier than crawling under low hanging branches with a ewer.
I have enjoyed plugging lights into a specifically wired outlet, one with a rheostat on it. This can tie the tree lights into the same plugs that handle the rope lights backlighting timbers. This makes for easy ambiance adjusting.
I cannot overstate the convenience of having an extra wide, even double, door into the great room. I had to protect my soft redwood door jambs with cardboard, during insertion. Taking a dried and stiffened tree out is even harder, and done without the festive attitude that accompanied the prior passage. I usually limb the tree out, prior to removal. I have, even, used a chain saw to do this; fun. I often killed two birds by having the tree leave the room as smoke and tinsel enhanced ashes.

Happy Holidays

Delaminating Beams

2009-02-14T15:41:00.000-08:00

Ben has been known to contend that: “The worst clients are desperate friends – you can’t even, really, take advantage of them on the fee.” So, what to say about a job that has “hit a glitch” and involves good friends on three sides? I got a call from one old friend one evening, and was on a ferry two days later. These spectacular curved beams were intended for some lovely trusses, designed by another friend, for inclusion in a home being built by yet a third friend. All parties agreed something was awry, but were unclear on what best to do about this. I showed up with a bag of tricks that included a bunch of sophisticated, new lag bolts. We were able to salvage the beams, the schedule, and a variety of friendships; through application of nimble engineering and good site help.

Bonderson Big Beamed Baby

2009-01-21T15:02:00.000-08:00

We thoroughly enjoyed working with The Cascade Joinery in building this lodge in California. The client is larger than life, the builder is way larger than we, and the site is larger than large; inspiring us to craft some larger than humongous key-laminated beams to support the roof. These must be the largest key-laminate beams built in North America for a century. The large seismic loads are absorbed in a series of significant steel moment frames that we detailed to be largely concealed within the walls. All in all, a very large amount of fun was had by all.

Publish Post

Derevyagin Beams

2009-01-21T09:17:00.000-08:00

This clever and fairly mechanized scheme is an example of industrialized keyed beams. They are pre-cambered, and make highly efficient use of smaller and square timbers to assemble deeper beams. We would love to build a couple of these to fill your long span timber beam challenges. If you actually arrived at this page through a search for Derevygian Beams? You and I really ought to talk (my cell number is 603-381-3810); and you ought to understand that you may well be a very troubled individual. The illustration is from one of my Very Favorite timber tomes - Wooden Structures - a 1960's work translated from Russian and long out of print.

Keyed and Key-Laminated Beams

2009-01-03T13:56:00.000-08:00

Builders have been making larger timber members from interconnected smaller timbers for thousands of years. Their goal is to simulate Mother Nature’s innate fiber connections, but with man-crafted interconnections. Glue laminating pretty much achieves our Mom’s high standard – but with some significant aesthetic and construction compromises. Key-laminated beams can be much better looking, maybe occasionally lovelier than Mom's.

The individual layers in any built-up beams want to slip by one another under applied bending loads. To the extent that we can prevent this slip with mechanical connectors (or "keys"), we can generate composite action among the various layers. The analysis, design, and detailing required to do a good job of key-laminating beams is not trivial. A good friend, Joe Miller, is pursuing his Ph.D. in the topic, for instance. But the resulting beams can support remarkable loads, while contributing all sorts of opportunities for joinery celebration. We have included these lovely beams in many of our designs. Call us, to get help with your own lovely composite, mechanically-laminated, keyed beam.

Timbers

2008-07-02T10:51:00.000-07:00

People use the terms “post and beam” interchangeably with”timber framing.” This is, actually, just fine with me. At least they are speaking of something that I love. For the record, I consider the distinction between the two to lie in the joinery used and the knee braces. Simple post and beam structures have been built for centuries and have been held together with all sorts of simple (toenailed spikes) and esoteric (hemp macramé wrapping) connection techniques. All the timbers in a wooden structure; posts, beams, braces, rafters, etc. are subject to interesting treatments – in material, orientation, or application.

Delaware Covered Bridge

2008-11-22T16:15:00.000-08:00

The State of Delaware chose Pocopson Industries to build the Town Lattice covered highway bridge to replace one lost to flooding. Ben has helped to build two of these already - one larger and longer, and the other lighter – but this is the first intended to carry vehicular traffic regularly. The bid documents included a schematic design which appeared to fully describe the timber superstructure; but the devil really is in the details – a lesson we seem constantly to learn anew. The effort was not simplified by having the new concrete abutments in place, meaning that our richly detailed structure had to fit within very rigid and established constraints. We included several features, including: portal steel moment frames, full-length glulam chords, added verticals at the supports, lattice plank sorting for quality at the span ends, and tuned Bongazzi bolster beams, that we like to believe old Ithiel Town would have admired and encouraged being added to his 1820 patent on the first generation of this remarkable bridge style.

Bizarre Mating

2009-01-22T09:00:00.000-08:00

I collect examples of the cast iron hardware that could be bought from catalogs by industrial building designers in the late nineteenth century. But one of my favorite examples involves only incidental ferrous fasteners. The builders of a railroad roundhouse in Quincy, Massachusetts had big and beautiful heart pine for their posts, but wanted to use the newly available and very efficient rolled steel S-beams. The fabricators punched hundreds of these 18 inch tall “I mortises” into the faces of the posts. Light steel angles and lags held the connections together. You can still see the drill and chisel tracks of what must have been a very bored crew.

Window in new tree house at Longwood Gardens

2009-01-22T15:38:00.000-08:00

A great old friend, Jake Jacob, builds some of the loveliest tree houses in North America with TreeHouse Workshop, Inc. He built a beauty for the lovely public Longwood Gardens in Pennsylvania. At the last minute (well, actually, well after that moment) he realized the huge window needed some engineering attention, if it was to resist the heavy design wind loading. Ben was thrilled, to get involved with helping a friend, while visiting a breathtaking site and helping to build a remarkable example of the fenestration craft.

Spline and block floor support

2009-02-03T15:52:00.000-08:00

Peter came to me with a design challenge/opportunity for the joist end connections that would point in toward the huge tree in the middle of the octagonal room. We needed to support some circumferential floor boards, inside the innermost ring of floor beams. A likely method was some form of joinery for the radial joists that would extend beyond the inner surface of the joist. We could make a horizontal spline with a clunky block atop it, or? We came up with a yoke spline into which a dadoed block slides against the inner face. The floor boards sit on this block. The block is, in turn, held in place by horizontal pegs through the spline. We drew a version that had vertical keys on either side that pulled the block along the spline into the joist, but calmer heads prevailed.

The Arch Stirrup

2008-03-08T08:45:00.000-08:00

Scissors trusses, including those with curved bottom chords, can induce a lot of tension in the king post. This makes "the crux" an important and challenging connection. Curved bottom chords are working hard, especially at this central point, so we try to use all that king post tension to hold up the curve without doing any more damage than absolutely required to the curve. This stirrup does the job with virtually no cutting on the curve. This stirrup is attached to the king post and goes around the curved chord in order to be able to push up on it from the underside. The tension in the king post is turned into compression on the underside of the curved timber. There are wedges between the two stirrups to spread the load on the underside chord surface, while allowing for adjustment during assembly.

Timber Stretching Joint

2008-03-08T08:46:00.000-08:00

This complex connection is a cutie. It represents every timber framers dream. It is, at least, one answer to the dreadful question: "How DO you stretch a timber, after you've cut it too short?" This was not the actual inspiration for this joint. We had two remarkable timbers that weren't quite long enough together to run the length of the building. We needed this joint, at the center of the building, high over the floor in order to stretch them to reach. The connection design started as one that would be assembled in place, with enough capacity to pull the timbers into line. But one thing led to another, and more pieces got added to the design, and by the time it was through the shop the site crew realized it was so sturdy and so complex that they would be better off connecting the two timbers on the ground and lifting the entire unit. Had I known this at the outset, we would have done it differently – but maybe not, given how dramatically this connection turned out.

Swallowtail Joints

2008-03-08T08:47:00.000-08:00

I remember when I first starting seeing these in my mind's eye and trying to describe them; the underside breaks on the post edge and feathers out like a swallow's tail. Since this was well before 3-D drawings became so common, we had to cut a sample to see it. The first one we cut showed up where cupola hips land on their supporting posts. Since then, braces and arches have generated these same pointy tails.

Count the Pegs

2008-03-08T08:48:00.000-08:00

Can you spot the peg difference? This is a picture looking down through the staircase running up through Jack Morway's four-story apartment building. The building is relatively tall and narrow, with the lateral bracing system and connections working pretty hard. The lateral forces get larger, the nearer to the ground they are. You can see the horizontal splines that resist the tension generated in the heavy braces that stiffen this building laterally. If you look at the splines toward the top, there are only three pegs. The same splines, lower down the staircase have four pegs and six pegs at the first floor. This is a unusually clear instance of joinery details reflecting the applied loads; and for this, I admire it.

A Post for all Seasons and Reasons

2008-07-02T08:51:00.000-07:00

The Sugarbush Base Lodge has two rings of double posts, all of them needing to be held in place and down. We wanted a post foot that would hold the posts from kicking out, while allowing us to tip them during assembly. A positive method of holding the posts down to the concrete was critical. Finally, a place to attach straps and comealongs to stabilize high and heavy subassemblies during erection surely would make our work easier and safer. The plates bolt to the concrete slab. The short pipe sections provide shear resistance, without undue restraint against tipping. The threaded coupler provides both the eventual hold-down capacity and the temporary construction connection. In order to assemble it, though, we had to cut a doubly deep mortise for the hold down block, in order for it to stash out of the way until we needed to install the final hold-down rod through it.

Compound Radial Wedges

2008-07-02T08:52:00.000-07:00

When you are trying to assemble an octadecagon; one that is big and heavy, and on a tight and pressured schedule, then you need every edge you can get. Connections that tolerate movement during assembly, while being able to provide clamping that pulls the structure into position are such a tool. The upper ends of lower radial rafters at the Sugarbush Base Lodge are under tension, generated by the long struts down to the doubled posts. We wanted to be able to tip the inner ring of post outward during assembly, so the joint between the rafter and posts had to be able to handle some sliding. Both the posts and the rafter were dadoed, anyway, so we just extended the dado on the rafters inward. This allowed the posts to tip out, while providing a bit of safety against their tipping TOO far out – as in falling over. When the rings were complete, we drove matched sets of compound wedges between the paired posts and the penetrating rafters. When the wedges were drawn up tight, the dadoes were bearing on the outer faces and we knew the hoop was closed.

Gambrel Dogleg Splines

2008-07-02T08:54:00.000-07:00

The second of the three (and counting, Jack?) remarkable Morway Projects was his four story apartment building in Cambridge, MA. The gambre; roof is covered in heavy slate. Gambrel roofs can be a structural nightmare, acting as five-pinned arches with the least provocation. Any more than three pins in any arch makes for a shifty mechanism; one that has to be held carefully in line. I used the ridge at this building as a lateral restraint against movement. It is a pentagon-shaped 10 x 14 on the flat. This ridge is intended to resist more lateral load than vertical – it also made for a ridge beam that was safer for “ridge dancing” as soon as it was up – just ask Jack’s magnificent and standard-setting-understanding spouse, Nancy. This ridge beam should be able to keep the gambrel roof from shifting from side to side, but we had to connect the upper rafters to the lower anyway, so why not add some suspenders to the ridge beam/belt? The rafters interconnect through “dogleg splines” shaped to the two roof slopes and made from high quality plywood. The peg patterns may not generate full moment capacity, but they surely made the roof more secure than all sorts of other joints I might have designed.

DNA Splines at KAF

2008-07-02T08:54:00.001-07:00

“How many angels can fit on the head of a pin?” is a question that comes to mind, all too often, when trying to connect too many timbers together at any one spot. This comes up, most regularly, in polygonal structures such as the King Arthur Flour dodecagonal (twelve-sided, for the Latin-impaired) building in Norwich, VT. At the top of this forty five foot tall, sixteen foot wide tower is a coopered king post to die for. The dozen rafters had no trouble finding a place to land at the top of the king (or crown) post, but the twelve horizontal timbers at the loft level were beyond jostling for space. What to do? The first part of the strategy is to cut the problem in half, by cutting off six of the radial members and putting wedged through tenons on them after they passed through a circumferential ring of headers. I connected the three opposing pairs of timbers that still made it to the axis with three separate radial splines that pass through the coopered post. In order to avoid THESE from colliding, I spread them vertically along the axis of the tower. The three splines spiral by one another, within the confines of the king post. The three pairs of timbers had to be unusually deep, to accept the vertical distribution within six coplanar timbers: a high, low, and mid-spline.

The Big Y

2008-07-02T08:55:00.000-07:00

This simply must be one of the wilder wooden splines ever conceived. Among the several challenges of any exposed valley joinery is that all the valley rafter and ridge joinery can often happen at the exact midspan of the supporting principal purlin. Just where we are trying to craft connections that fully and strongly hold the valley rafters up, the purlin has all it can do not to break even without a lot of mortising and peg holing. The two Big Valleys at the Carolina Country Club met in the middle of a twenty four foot long purlin and they really needed to be held up there, in order not to be inducing a lot of spreading at their feet. The challenge boiled down to grabbing the tops of the valleys and supporting the intervening ridge beam, while doing minimal damage to the 10x16 purlin. The Y-shaped spline, crafted from plywood, was pegged into the interior faces of the valleys, held in place with a wedge rather than pegs, and passed through the purlin above the ridge. [This is, certainly, one of those instances where a photo and drawing are worth more than another thousand words]

Art in a base plate

2008-11-22T08:56:00.000-08:00

This is the most amazing post base plate I have ever seen. It is scribe fit to the broccoli-like shape of the western red cedar log post. The post sits on bearing strips welded in a radial direction that are intended to let the water out of end grain, while letting the post shrink without hanging up on the bars. We left a hole in there for all the water to get out. Then we galvanized the whole thing. That’s Bill Holtz, the architect of this gem home, head sticking his head through it.

The Existential Drip

2008-12-22T08:58:00.000-08:00

This may be My Favorite Connection. The combination of client, setting, process, and product is irresistible. It all started simply enough: when a timber is wider than the timber in which it terminates, “something needs to happen.” Most times, we simply taper it into a smaller timber; one that fits more readily and elegantly. This tapering gets boring pretty quickly, since the only decision is how long is that taper – a relatively random and meaningless dimension.

In a crucial spot, high in a dramatic space at the core of an amazing home atop a wonderful hill overlooking La Bras D’or (in Nova Scotia, eh?), we had a ten inch wide post landing on an eight inch wide timber. When I sketched and proposed my "drip solution" to the crew, I met with fairly universal wide-eyed stares. Way too weird for them, let alone the client, thought all. A mockup was in order. I talked Brian Smeltz into helping me to build it and to hang it from an overhead hook for the client to see. The Drip has carved pieces on either side that stand proud of the supporting timber and extend past it, carved to appear to be melting around it. Furthermore, there is a center “tenon,” also carved to appear to be melting through the supporting timber. I was physically restrained, from hanging a literal drip of wood from one of them, on a monofilament line. It can be good, to have "The Top" pointed out by others, before you go over it.

As we walked the client up to the prototype drip, I explained where we proposed to put it, prefacing it by warning him that this might be more statement than he wanted in his home. Bart Weller looked up at it, looked up at me, and said: “Why not?” Brian and I turned toward one another. Our Favorite Line, from one of our Favorite Films – The Wild Bunch. The most existential line in a remarkable film. William Holden has walked into a room full of his equally disenchanted, functionally obsolete, fellow gunmen. He is strapping on his sidearm, preparatory to taking on an entire Mexican quasi-army. He says to a pair of brothers, played by Warren Oates and Ernest Borgnine, “Let’s go.” The brothers look at one another, and one utters Bart’s line.

Tragically, Bart fell to his death; landing at his wife’s feet, just days before we arrived to start erecting what remains one of the more special timber frames I know. I could tell tales about this project, the people involved, and the raising process, for hours. But I won’t. Well, OK - but just one: Joe maintains the BWC yard and is a pillar of reliability and physique. He came to me, soon after we had cut The Drip and told me that he knew why I had done it – because each peg now passes through four shear planes, rather than just two. I looked up at him, chuckled, and STILL wonder if he was teasing.

Inboard Posts

2008-12-22T10:49:00.000-08:00

This thoroughly hip house in Kearny, Nebraska (who knew?) incorporates those fancy Pella corner windows with the sharp bend in the glass. The client loved these units and was not going to accept any posts in those two corners with the prairie view. We pulled the posts in the corners, and spun them forty five degrees. This spin made the hip (rafter) joinery easier and allowed the arch for the eyebrow dormer to land in a swallowtail joint. The client followed through with elegant detailing and great color schemes, throughout the rest of the project. The architect on this project, Paul Irwin, worked with Benson Woodworking for only a couple years, but designed a few homes during that time that include what I consider to be some of the best examples of interaction between building and frame.

Bowstring Timber Trusses

2009-01-03T08:40:00.000-08:00

If you can spare the attention while driving through older urban industrial areas, you will notice a lot of bowed roofs. Most of them, should you get inside and look up, will be supported by bowstring trusses. The curved top chord may be glue laminated, but might just be bent, nailed and bolted planks. The web members can be discrete single timbers or overlaid planks in a lattice configuration. These trusses were economical in spans from forty to one hundred and fifty feet. They are the most efficient form in spans greater than eighty feet. I remember looking up, as I took to the roller rink on a “Honky Night” at the Roxy in Brooklyn, and noting: “Wow, Town Lattice bowstring trusses!” The non-honky taking my admission had not heard this reaction before. I have used glulam timbers in the top chords of a set of these holding the roof in a lovely new sculpture studio in New Hampshire and would welcome any chance to build some more of these lovely roofs.

Thick, REALLY Thick, Front Doors

2009-01-03T09:12:00.000-08:00

These “destination doors” are thick, multi-jambed, and heavy, with a distant-pivoting axis that induces distinctive opening movement – these babies MOVE, not just swing. The doors have double jambs, like bank vaults, with the associated great air seal. In order to further reduce the pinch on the flashing (while hugely upgrading the “wow factor”) the heavy strap hinges pivot from a point a couple feet outside the door jamb. This means that the door moves in, as it is opened, as opposed to swinging in. This is a door that your entire town/village/city will note and knock upon, just to feel it open in front of them. Call us, for details. One of these doors justifies both heavy posts along walls and large entries. We have German sources for the spectacular heavy hinges required, and Italian sources for the exotic hardware at the corners of door framing. You will never regret sponsoring the first of these doors in your own sphere of influence.

Elevated Timber/Panel Second Floor Systems

2009-01-03T09:13:00.000-08:00

While I was working with Benson Woodworking, we developed what I believe to be the highest value second floor system available to any home builder, anywhere. BWC offers it in their Open-Built™ homes, but the system would work in most new stick-built homes. The components are, in order of installation: exposed girts and joists (they can sit on a few interior timber posts, too), prefabricated large sheets of heavy elevated second flooring, and prefabricated ceiling pans - that set in place, atop the timbers and hide the wiring, ducts, plumbing, and can lights. The advantages of this system include: great looks and higher ceilings, stiff second floor, quiet floor, readily fitted with services, readily repaired and remodeled surfaces. This really is the Floor of the Future. Akin to having your second floor as easily dealt with as is your typical first floor in a home with a basement. Or, like installing a commercially viable suspended ceiling – but one that is a whole lot better looking. We used one in Steve Thomas’ sweet new barn in Maine. Please call us if you are interested in having us provide a signature ceiling for the first floor of your otherwise standard home.