Stopped in on a local seafood and chophouse restaurant upfit we contracted for a look at the ceilings going in. The poplar lumber was processed in our shop; planed, ripped to various sizes, sanded, then transported for installation onsite. Poplar is an ideal stain or paint grade receptive hardwood, which inherently does not have a rich color or spectacular grain. It’s ability to blend in to architectural settings make something relatively bland quite beautiful. We are using a non grain raising stain in which the first coat is stained and two layers of top coat are applied, which are precatelized. This approach will create a mahogany like appearance, adding style and shadowbox flare to the ceilings. Coffered ceilings such as these capture light, emitting shadow lines with rich visual interest. There are secondary benefits as well, the coffered ceiling has acoustical properties of sound absorbtion reducing echoes and noise. They hide unsightly wires, flex ducts from HVAC units, and house lighting fixtures. All these features, plus a warm rustic feel, add a dimension of invitability this restaurant will capitalize on in the future.
Archive for October, 2011
Update 11/21/11 When I arrived onsite the last section of steel was being set by the Lull and welded into place. Much progress has been made on the interior wall framing and 2nd floor trusses are set into hangers butting the ICF walls. The steel beams were packed out with alternating 2×12′s and 2×8′s to fill the center “I” so they could receive the floor trusses as well. Tom, the ICF man, had determined these trusses butting the packed out steel needed to be 2 1/4″ longer. His knowledge of what had to occur to make the different trades interface with the ICF system has proven to be invaluable both to me as a vendor and the homeowners who appreciate everything fitting together as it has. My primary purpose for this visit was to measure and approve the shop drawings for the roof system. It was decided to separate the upper roof system from the lower roof system in the interest of having product available while the second floor ICF system was installed and pumped. The master suite on the left side and lower roof behind the large steel beam is where we concentrated for this approval. Due to the varying plate heights, different bearing conditions and general verifications of truss profiles, this can be a daunting task. Breaking this into two different roofs was helpful from the standpoint of critical examination against the existing framing conditions. Even though Auto-Cad permits 3D perspectives in truss design, evaluating how each component fits in the field assures the correct profiles are sent into production. There is no short cut in measuring and reviewing each design individually, especially with as “busy” as these site conditions are against the plans. With the drawings approved onsite, the noted design changes will be made and then will be evaluated by a structural engineer and sealed. From there they will enter production, be cut on component saws, manufactured on the gantry system, stacked and banded in the yard, loaded and delivered all with 5 working days. You could probably ask for more but I don’t know if you would get it.
Update 11/17/11 Towards the end of last week I have observed the steel beam is in place pre-drilled for 5/8″ hot dipped galvanized carriage bolts. The “I” portion of the beam will be packed out with the combination of 1 2×12 and three 2×8′s. I learned the treatment ACQ (Alkaline Copper Quaternary) is “reportedly more corrosive to steel” than it’s predecessor CCA, which was phased out in 2003 because it contained arsenic. Seems protecting lumber from fungal growth, moisture, and bugs can be a pretty nasty process, doesn’t it? The switch out to southern yellow pine bolted into the steel (this is what is meant by the term “packing out”) will interface with the floor truss hangers completing the connection between wood and steel. You can see from the photos where the ICF walls are the carrying member for the second floor, LVL’s are bolted into the concrete which leads to the other significant event that occured on Tuesday of this week. Look at the photo Tom took on his cell phone and shared with me. It shows the pump truck extended out 22 meters (the equivilance of 70 feet) pumping the concrete into the prepared forms. The pump truck’s capacity is 47 meters, and it needed all of that due to the fact it was positioned 120′-0″ from the back corner. The process requires elevation to create velocity when pumping the concrete through a 5″ tube reduced into 3″ tube and held slightly above the forms to pour. These forms required extra bracing due to the height (the master suite walls were 14′-0″). In reviewing the other photos, pay attention to the zero corner pocket sliding glass doors which is one of the many special features of this house’s floor plan. If you look closely you can see the 90 degree corner etched into the concrete. This allows the doors to fold back into themselves clearing path from the leisure room to the side porch and an unobstructed view to the waterway. It will require a girder truss receiving the concentrated load from a laminated beam since the walls below cannot be used as support. Originally the plan had shown steel in this location, but we were able to economize somewhat by using the beam / truss combination instead. The owner had the savviness to see this and is due all the credit for the idea. I was in the master suite reviewing some roof truss details when the wood framing contractor was laying out the walls for the master suite and overheard the discussion with the owner. The owner went on to explain when the doors for the master suite were open they would align perfectly with the center of the wet bar all the way across the house. It reinforced the need to have effective listening skills in the realization of becoming a quality supplier. It was obvious the owner had a very specific conception of how his house would come together.
Update 11_3_11 Slow but steady progress is being made setting the forms in preparation for the first floor pour. We have delivered the LVL’s which the floor trusses will bear into as a ledger connection on the inside of the ICF walls. Methodically we pull dimensions to verify lengths against the plans. More importantly, which bearing conditions each floor truss will interface with in conjunction with the forms. It matters if the floor trusses bear directly into the ICF wall, or if the floors hang to the side of the steel beam, with the third condition being lower roofs bearing on conventional ledger boards. Each one of these factors impact the length of the trusses we are producing and require their own metal connection. Each truss is custom built and non returnable so a mistake at this point will require at the least, a sealed repair drawing or at the most, a rebuild of the incorrect trusses manufactured. Everyone is involved and must agree on what needs to be built to avoid problems like these, because each of us have a vested interest in the floor trusses coming out correct. Lost time is another consideration as mistakes can entail delaying the next phase of construction. Once the ICF 1st floor walls are poured and the ledgers installed, the floor system will begin the interior wood construction phase and require the wood framing crew to start working onsite. They will be occupied with deck construction when the first floor system is complete while the ICF crew works on the second floor forms to be poured. Meanwhile, the roof truss system is being designed and both the lower and upper levels will be verified prior to their construction. On the perimeter of the outside deck roof level, beams will be installed to receive and create bearing for the lower level roof trusses. One thing is for sure, the pace will pick up once the wood framing starts and there will be no margin for errors in scheduling the ICF crew to finish and the wood framing to move upward towards the finishing of the roof system to complete dry in.
Update 11_1_11 Ominous Halloween skies did not prevent us from taking measurements for the floor system. Don’t fret, no one was actually rained upon during the time sequence of these pictures being taken. As the forms are going up it is time for making sure the 2nd floor trusses will fit into the 1 3/4″ LVL ledger boards via hangers. There is a particularly difficult section where the floor height above the finished floor is 24″ deeper from one point to another as it transitions into the huge steel beam in the back. The plan simply shows a straight LVL from point A to point B where a column is located. Problem is this arbitrary point of descent occurs mid-lenght, down the proposed LVL interior bearing just out the wall of bath #2. Since the floor trusses are 18″ deep, there would need to be a 6″ height change to make this happen. We know a 24″ LVL will not work because of the 6″ required change midstream so another solution was required. Settled on a flat girder, multi-ply, which could be manufacured on the 2×4 orientation (as opposed to the floor 4×2) and have two bearing points at different elevations. It was my solution paralleled to Schrodinger’s cat regarding interference as it is in multiple locations at the same time. At least that is my story. I am shipping the ledger material so that the first level can be poured, the second level floor trusses will be set before the ICF installer, Tom, can finish the second level. Progress in delicate proportions is so rewarding.
Although I have concentrated on illustrating energy efficient wood structures, this alternative has many beneficial features worth reviewing. Insulative Concrete Forms (ICF) shown here are being used as the wall system for a 11,000 square foot house under construction which I am supplying the roof and floor trusses for. The 4′-0″ x 16″ tall forms generally coming in 12′-0″ sections fit into a metal track system, held apart 6″ in the center by plastic ties. Between the forms will be poured concrete creating a super fortified structure. The energy efficiency is derived from no air infiltration which means a lower cost for heating and cooling. It also means virtually a dust and bug free living space. Concrete is sound deadening contributing to the elimination of noise pollution. But, the greatest value is of a structural nature. ICF homes are perfect for areas of the country which face environmental risks such as high winds generated by hurricanes and tornadoes. The fire rated assembly deters the spread of flames for up to 4 hours. This particular house offers a variety of challenges in the construction phase. The ICF installer and myself as the truss supplier will be wrestling with 16 different plate heights not to mention the raised and furred down ceilings in nearly every room of the house. We have decided to coordinate the truss layout and wall heights against the plan to assure we are singing from the same choir music. Any alteration in the plan can and will affect subsequent levels and tasks moving upward and I have yet to see a house built “per plan”. The ICF installer will pour the first floor walls then the 2nd floor floor truss system will attach to 1 3/4″ LVL ledgers installed on the face of the walls. The second story walls will go up after that. The roof system carries spanish tile and is loaded with additional dead load to compensate for these heavier concrete tiles. There are a number of engineered wood beams used as headers I will be supplying, so the interior of the house will be wood along with the trusses. There is a huge steel beam to sit on the columns shown in one of the photos that carries the weight where there is a 24″ dropped section at the first floor level. The ICF structure will stand intact for centuries versus decades for the conventionally framed wooden house, another testimony to it’s durability.
I was in Holden Beach, NC the other day reviewing shop drawings for an upcoming piling house with a general contractor, and spied the beautiful curved stair we installed earlier this year. Happened to be directly across from it on the island and it just looked so majestic standing there above everything else. On some earlier posts, I showed the manufacturing process in the shop and even showed it loaded to be transported to the job, but after seeing it from my vantage point the other day I decided feature it here. The stair leads from a small bar with a large view to the “widow’s watch” above. This was the “coming together” event which merged the two separate businesses of Dunn Metalworks and First Flight Stairs. The building of this aluminum spiral required the expertise of a stair builder and a welder creating a synergy neither one could accomplish alone. Since then we have several others joint projects, more spirals, aluminum railing jobs,and unconventional things like steps for a boat dock. For small businesses, the ability of being able to count on resources outside of their sphere of expertise expands the thought process of what is possible. Maybe a slight consolation in the midst of a turbulent economy, hopefully, to be in a controlled spiral upwards rather than a uncontrolled one downwards…
From design through manufacturing, the truss / wall panel fabricator’s experience is not complete without stacking and banding the product in the yard. The other extremely important task, and often overlooked, is delivery. Once the trusses are built on the gantry system (see Truss Mecca for manufacturing process) and make their way the length of the building through the final press roller, they are checked for plate placement accuracy, then stacked on racks or sorted on “runners” on the ground. Similar trusses are banded together in packs which makes them unified for the delivery process. It’s a good thing too, because most of the time they are loaded on a 48′-0″ roller bed trailer, chained down and secured before heading off to foreign ports. Trusses can be oddly shaped, requiring special overwidth permitting for truss packs over 12′-0″ wide. Once they arrive at the jobsite, the driver has to size up the lot for placement, dealing with unlevel ground and general construction material obstacles as well. For the extra wide loads, an escort truck is required in front with “WIDE LOAD” banners and a orange hued caution light to alert traffic of their arrival. Depending on the size of the load, one escort is not enough and another trail’s in the rear. In the case of the wall panel deliveries, a moffit truck shown here unloading a panel delivery, is required for appropriate placement of the panel “stacks”. Actually, not all of the competitors use moffit trucks for unloading. This is a Builder’s First Source exclusive in our region of the country. With the need for the wall panel delivery during the earlier stages of construction, they have to compete with other materials for space. The moffit truck makes this practical, postioning “stacks” where they will ultimately be used. The truss delivery is certainly a more dramatic offloading proposition. The bed tilts downward to allow gravity to do it’s wonderous work, but it is still about 24″ off the ground when the trusses roll off. There is a jerking motion to start this downward trend; it makes some horrendous creeching noise as the tractor / trailer moves forward while the load lays down where it once was. Honestly, I hate to watch. Selfish reason, trusses requiring repairs need to be certified by a structural engineer and yours truly is responsible for getting it processed. Satisfying customers, getting the product safely to the jobsite, in the correct position for setting without damage, are all aspects of a demanding position required by our delivery personnel.
Builders First Source Coastal Component truss plant located in Loris, SC had manufactured this unique truss type recently. Once considered a difficult truss to design, it is now handled quite easily through segmentation of the top chord. The radius appearance creates a special look that is very popular in modern architecture. Earlier, the bowstring design was popular in urban areas, primarily designed out of heavy timber trusses. Typically, these structures were massive clear spans with the distinctive shaped tops being made out of straight timbers cut into curved shapes. The splice points were thru bolted as were the junction areas on the straight bottom chords. Now there are a number of issues which have arisen regarding the design assumptions, to which the buildings in question have been described as “an accident waiting to happen”. Most of this fracas developed from tensile strenghts as prescribed by early building codes. The bottom chord of the truss was the centralized point for load distribution, and the reduction factor was revised to accomidate such loads. Other problems related to snow loading being incorrectly compensated for allowing for drifting that lead to failures. Fortunately, the trussed version of this audiciously familar shape has none of the difficulties experienced by it’s predecessor’s
In an unprecedented decision on October 6th, 2011, it was announced the Southern Pine Inspection Bureau would be decreasing the values of structural lumber. This abrupt change in the design criteria is slated for vote by the American Lumber Standard Board of Review on October 20, 2011. If passed, the SPIB findings based upon the visual grading of a sample size of approximately 7000 boards, the design values of all grades and sizes of southern pine lumber will decrease by 25% to 30%. If this vote passes, it will have a crippling affect on the wooden truss industry in particular. The predominately used lumber for structural purposes is southern yellow pine. The makings of the perfect storm for a troubled industry. New construction at near all time lows coupled with the devaluation of existing inventories, not to mention what losses would experienced in design. You see, specifications of each individual job goes through a design process which ultimately is sealed by a structural engineer where required. All designs would have to go through a redesigning process with the lessing of the established standards, then resealed. Multifamily projects started under one set of values could literally change overnight after the 20th vote. Who would pay for this sudden shift of reduction of values and prices? Maybe a better question should be what has the SPIB doing for twenty years? Juvenile lumber and the harvesting of short growth forests products has been going on for years. Instead of a gradual implementation, the SPIB makes the decision to give 14 days notice to this potentially industry stifling move?
“That action could have a dramatic impact on a lot of the existing Southern Pine in the supply chain,” said Michael O’Brien Southern Lumber and Building Material Dealers Association President. “We’ve been very critical of the abrupt announcement and quick approval.”
“If they find the quality is less, we don’t disagree with changing the design value, but we do disagree with changing it overnight.”
Timberology is requesting as many Home Builder’s Associates, concerned builders, citizens, manufacturing facilities and lumber dealers to voice their displeasure as soon as possible to Washington, through their political representation prior to the vote on the 20th.
Update 10_19_11 Great news from the Board of Review, American Lumber Standards committee today as it was posted there will be an additional 60 days granted before implementation of the proposal from SPIB. The Forest Product Laboratory review has “only recently become available”. A second meeting will be held to address concerns regarding the “technical aspects of the SPIB submission”. Don’t think anyone is faulting the lessening of the values, just a brief period to prepare for the upcoming changes. At least there will be time to filter through the ramifications….
Dunn Metalworks was commissioned to manufacture the sign leading to the football stadium by the North Myrtle Beach Boosters Association. Here are some photos of the work Eric did with his plasma cutter and welding equipment. The large sign was erected the other day and is quite eyecatching and received much critical acclaim from all who have seen it. It was prepared for the homecoming game this weekend, but locals will have few “gametime” experience to enjoy this season as there is only one remaining home game left on the schedule. The Chief’s will have many future opportunities though as this sign’s beauty will spread NMB spirit for generations to come.
An article from Nature Magazine, probably missed by many, illustrates man will be held accountable for his negative impact regarding the treatment of nature and the environment. The first major Arctic ozone hole was observed last winter, leaving a gaping hole in it’s stratosphere. Seems this has been a annual occurance (since 1985) in Antarctica, but until last winter, the Arctic had been spared. Holes in the ozone layer naturally occur at the coldest regions of the earth. Antarctica’s strong winds typically isolate it from other warmer circulating air currents, making the frigid air above it susceptable to ozone depletion. This marks the first time the Arctic recorded such massive losses in the protective barrier of the ozone, however. The protective barrier which the ozone layer provides is the fact it absorbs 97% to 99% of the sun’s ultraviolet light.
Causes of the erosion of the ozone layer are directly linked man’s use of chlorofluorocarbons (CFC) used in aerosol cans for many years and for refrigeration (think of car air conditoners units to mention just one), now banned for use. The consequences of a continual depleted ozone layer for man are severe. In blocking these harmful UV ray’s from the sun, it protects us from the advance of skin cancer. Plant’s on earth surface would be greatly compromised in the photosynthesis process, which requires the absortion of light to convert carbon dioxide into sugar and ultimately oxygen. At a marine level, plankton life would be affected in their role to remove carbon dioxide and to be the basis of the food chain in our oceans. The need for an ozone layer for human and plant protection is evident, but it needs to be distanced from the earth’s surface. The ozone layer is a form several different types of oxygen enzymes, but if it was present on the earth’s surface it would actually be a poisonous gas. What can we take from this? Mainly to heed physical warnings. Obiviously we cannot undo the past sins we have created. Back in the 70′s, when it was discovered the havoc CFC’s and green house gases were having on our atmosphere, international treaties were created to halt the production and use of the detrimental items. Forty years later we are dealing with the lingering effects. Now we have “bigger fish to fry” as global warming waits in the wings. It is time to put aside the political and economic differences long enough to be proactive and slay the monster who will most certainly, left unaltered, consume us.
Sustainable forestry represents responsiblity for the management and maintenance of the natural resource that occupies one third of the earth’s land surface. Forest’s represent two thirds of the leaf area of land plants. They contain 70 % of the carbon present in living things. To give some significance to that final figure, you will have to watch this video. Responsible care of our forests is the prevention of “clearcutting” and the assurance seedling are constantly replenishing felled full growth trees to allow the cycle of life to continue. The Sustainable Forest Initiative (SFI) was formed to encourage social accountability and awareness by clearly certifying those products that adhere to the initiative’s rigorous attributes. Products that meet the “green” standards, like CLT (cross laminated timbers) showcased in my previous post, are recognized because of being “manufactured from low value, small diameter trees and trees killed by insects and diseases” The impact sustainable forests have on our lives is more than just the air we breathe. There is soil erosion control, the creation of habitats for all types of animal species, the creation of jobs for our citizens, clean water, recreational facilities, not to mention aesthetic qualities. Who said it better than Joyce Kilmer in her 1914 poem?
I think that I shall never see
A poem lovely as a tree.
A tree whose hungry mouth is prest
Against the earth’s sweet flowing breast;
A tree that looks at God all day,
And lifts her leafy arms to pray;
A tree that may in Summer wear
A nest of robins in her hair;
Upon whose bosom snow has lain;
Who intimately lives with rain.
Poems are made by fools like me,
But only God can make a tree.
The hybrid of wooden timber panels has arrived and the future of wood structures are looking very bright. Introducing Europe’s shining star to the lumber industry CLT, cross laminated timber. It is made of bonded cross laminated single layers called lamellas , which can vary in thickness, typically 3, 5 or 7 layers. The manufacturing process takes longer, finger jointed lamellas with glue on top coupled with a layer of shorter ones turn 90 degrees to arrive at the thickness desired. What results is a laminated panel that combines the qualities of air tightness and fire resistance, with thermal and acoustical insulative values to create a product to compete with traditional concrete and steel construction. Previous to CLT’s inception, wood structures by code could not exceed three stories in height. Shown in the photograph here, the Waugh Thistleton Stadthaus is currently the tallest wooden structure in the world. Studies conducted in Japan have classified CLT structures as “earthquake resistant” as the material has fared well in all testing to date. Constructing multi-story dwellings in wood is certainly more cost effective than the alternatives in terms of cost and duration. The greatest value, however, is the reduction of the carbon footprint wood construction affords for our environment. I love this short explanation of photosynthesis because it never hurts to reaquaint ourselves with the fact trees and forests create the air we breathe. The use of this new, innovative product is another earth sustaining move towards ecological sound judgement in our choices of building materials.