Some construction methods are used only in iso-lated areas of the country. Not too many yearsago, the majority of tilt-up projects were in Flori-da, Texas and California; that changed for tilt-up.

In masonry construction, prefabricated brick pan-els fall into this category of isolated use. Prefabricat-ed brick panels are conventionally-built masonrywalls or elements that are hung onto the building aspanels. These panels are prebuilt masonry, not pre-cast panels with embedded thin brick. Why is a systemthat has proven viable and profitable used so infre-quently in most of the country? Conventional wisdomsays that there is a lack of knowledge and experience.Perhaps the investment in equipment and facilities ismore than most masonry contractors want to make,or there could be some lingering concerns over theproblems encountered by Sarabond panels.

Choosing brick panelsIn the Pacific Northwest, KPFF Consulting Engi-

neers, Seattle; and two construction firms: BarkshirePanels Systems, Federal Way, Wash.; and L.C. Par-due, Portland, Ore., have been using brick panels forover 20 years. In Ohio and surrounding states, Vet-O-Vitz Masonry Systems, Brunswick, Ohio, has beenbuilding with brick panels for over 30 years. I thinkthere is more work in this area because of the compe-tition between us and Barkshire, says Lenny Par-due, explaining that customers feel more comfortablewhen there is a choice. Barkshire is our only compe-tition, he continues, but emphasizes that we almostnever compete for the same job. This is becausemost brick panel jobs are negotiated rather than com-petitively bid.

Fred Galassi of Barkshire stresses that, Our com-petition is not conventional laid-in-place brick.Rather, brick panels compete with other skin sys-tems such as glass, metal or precast panels. Weusually are competitive with precast panels, but whenthere are articulations on the panel then brick ischeaper, he says. John Tawresey of KPFF agrees,Brick panels usually are less expensive than precastpanels or conventional brick, but more than EIFS.KPFF has designed this system for use on more than75 buildings from Los Angeles to the Canadian bor-der and east to Boise, Idaho.

Their advantages over laid-in-place brick

By William D. Palmer, Jr.

The power of prefabricated brick panels

A brick panel cures in the yard while waiting to beshipped. Panels can be moved the day after fabrication.

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Advantages of panelsWhen an owner and an architect decide to build,

they usually have a look in mind. If brick is part ofthat look, they should consider brick panels. In thisarea, it is always an option for architects who wantto put brick on a building, says Tawresey. Anythingyou can do in concrete we can do in brick.

Panels have great design flexibility since each oneis custom-made; on some projects there could behundreds of panels with every one being different.Panels can incorporate precast pieces (such as forwindow sills) and even steel embedments for mount-ing windows. Complex shapes, such as sloping sills,arches, corbelled soffits, or articulated parapets thatwould be nearly impossible on the jobsite, are easi-ly built in the factory. For example, on panels thatPardue made for the new Seattle Mariners baseballstadium, the walls corbel out 34 inch per course onthe top 8-foot-high panels for a total deviation of 2 feetfrom plumb. This is one of the places brick panels ex-cel, notes Pardue, since braces were constructed onthe ground that would have been cost prohibitive

Panels arrive supported by an A-frame on the truck bedand are soon raised by crane for hanging on the building.

Tower cranes allow greater speed and flexibility in panelsetting.

Prefabricated brick panels are designed in the sameway as reinforced hollow clay masonry walls. Eachpanel is a self-contained structural system capable ofhandling the loads encountered during lifting andtransporting and after being put into service. Thebiggest difference from conventional hollow clay ma-sonry is that, since the panel is hanging from connec-tors at or near its top, the entire lower portion is intension and the panel behaves as a beam to supportits own weight.

Prefabricated brick panels are designed as rein-forced masonry, which means the panel has to crackbefore the reinforcement starts to contribute tensilestrength. Aesthetically, however, it is unacceptable forthe panel to crack. All tensile forces must therefore beresisted by the masonry assembly. Designers havebeen able to achieve this with standard mortar and thespecial brick units used for the panels. This mightseem an ideal application for post-tensioning the re-inforcing steel, which would allow it to contribute ten-sile strength without the panel cracking, but that hasnot been the case. We have considered it, saysKPFFs Dill, but its just not been necessary.

The best resources currently available for designersof prefabricated brick panels are Notes on the Selec-tion, Design and Construction of Reinforced HollowClay Masonry which covers general design of rein-forced brick, and Design Guide for Structural Brick Ve-neer which covers some issues more specific tobrick panels. Both were published by Western StatesClay Products Association and written by KPFFConsulting Engineers. These books are available fromWSCPA (213-388-0472) and from The Masonry Society(303-939-9700).

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Although brick panels are intended to act as rain barri-ers, drainage systems are always provided for water thatmanages to infiltrate the wall. Wind-driven rain can pene-trate minor wall defects and water cantravel by capillaryaction through hairline cracks at the unit-mortar inter-face. Various configurations are used to drain waterdown the back of a wall and past floor levels, which of-ten are at intermediate points behind the panels. Bark-shire uses different systems to get water out of a wall,depending on where the connectors are, whether or notinsulation is installed behind the panels and what kindof fire sealant is required behind the panel to providefire separation between floors. Water is routed past floorlevels and fire sealant and into window heads fordrainage from the wall. Flashing sometimes is used as afire sealant if drainage is at floor level. Completed wallsare tested with a water spray to assure the drainage sys-tem is working as planned.

Most brick panel walls are not insulated, depending in-stead on insulation in the metal-stud interior wall. Be-cause of all the connections that must go between thepanel and the building frame, rigid insulation and vaporbarriers can be difficult to install. Barkshire, however, iscurrently installing insulated panels on the King StreetStation in Seattle using their full back-up system (seebelow). Vet-O-Vitz promotes their Air Barrier System,which is a panel that comes with foil-faced insulation anda vapor seal.

Drainage and insulation

50 feet up on the wall. This is also where brick pan-els have a big advantage over precast panels: sinceevery panel is custom-made, each one can be differ-ent. On a precast panel, if every form had to be dif-ferent, the cost would skyrocket.

Cost is one factor to consider, and where brickpanels prove especially economical is on tight siteswith tight schedules. Since prefabricated-brick-panelconstruction requires so little onsite masonry work,it consumes a lot less space than conventional brick

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*Intermediate lateral connections are attachedto tube steel located behind brick column panels.

Microsoft-AugustaInterlocking by-pass flashing system

Windowhead

Interlocking by-pass flashing

Column embed

Lateral connection*

Dead-load connection

Concretecolumn

Redmond Town CenterBy-pass flashing system

Metal headflashing

Lateralconnection

Precast head

Dead-loadconnection

By-pass metal floor flashing

Precast sillDead-loadconnection

1 14 inch rigidinsulation foilfaced, two sides

34 inch air space

Lateralconnection

Head flashingKing Street StationFull back-up system

construction and the onsite congestion is greatly re-duced. And since the panels are made indoors, con-struction can proceed 24 hours a day if necessary andin any kind of weather. The panels can then be erect-ed in nearly any weather conditions which allows thebuilding to be closed up much more quickly thanwith site-laid brick. Another big advantage is that

scaffolding virtually is eliminated sincethe panels are set by crane. Scaffoldingcan be a major expense on a tall building.

In the western United States, prefabri-cated brick panels have two additionaladvantages over laid-in-place brick due tothe regions emphasis on seismic perfor-mance. First, since brick panels are rein-forced, they perform as a structural ele-ment, unlike typical brick veneers.Second, they have an outstanding abilityto be isolated from the building frame.Brick panels are the best option whenyou need to guarantee to the owner thatno brick will be on the ground after anearthquake, says Steve Dill of KPFF.

On the roadPanels are moved by truck from the

plant to the building site. A heavy A-frame is attached to the truck bed to sup-port the panels during transport. Ship-ping dictates the maximum panel height,since panels must be able to clear a high-way overpass. Great care must be usedduring shipping to avoid overturning thetruck or shifting (and cracking) of panelsthat can weigh as much as 20,000 pounds.Panels are delivered onsite in sequenceand installed almost immediately. Ideally,all panels should be constructed before the

first panel is shipped. That is the goal, although some-times a few remain to be completed, says Galassi.

Connection to the buildingPanels come in two basic configurations: spandrels

and column covers. In a typical building, spandrel

Returns were designed on this building between column covers andspandrel sections, allowing joints between panels to integrate intothe building faade.

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Prefabricated brick panels are built from hollow claybrick units that allow reinforcement to be installed inboth directions. All reinforcement on Barkshire and Par-dues panels is internal. The Vet-O-Vitz system is slightlydifferent in that, especially on panels with returns orsloping sections, an external structural steel frame is an-chored to the panels back.

Panels vary in size according to the job and applica-tion, with a typical panel being 7 feet high and 30 feetlong. Such a panel would be reinforced horizontally withtwo #3 reinforcing bars in each bond beam and verticallywith #4 bars at 4 feet on center. Bond beams would be lo-cated at the top and bottom of the panel, above and be-low the level of the dead-load connectors and at the levelof the lateral connectors.

All panels are fully grouted using high-lift grouting tech-niques. A very fluid grout containing grout aid is used.The grout aid improves flow through the wall (a plasticiz-er) and helps fill the voids left by the absorption of water(an expansion agent).

The panels are built indoors. Pardue and Vet-O-Vitzbuild theirs in a large warehouse and move them to the

side the next day to await delivery to the jobsite. Bark-shire has a unique system that uses a movable metal en-closure mounted on railroad tracks. Within this enclo-sure, five or six panels are constructed usingconventional hollow clay masonry construction meth-ods. The enclosure is then moved forward, leaving thecompleted panels outside and providing a controlled en-vironment for the construction of additional panels. Thecompleted panels are then washed and dampproofedwith a clear water-repellent coating. They are then al-lowed to cure for at least seven days to gain enoughstrength to be moved to storage and to await transport tothe building site.

In addition to the standard panels, which act as spandrelbeams, column covers are also manufactured. These can beflat or can have two or three sides to box around a column.

Before construction begins, all required materials areprepared, including reinforcing steel and any embed-ments. When the masons begin to work, all materials andany special architectural features are ready. Barkshireuses teams of two masons and one hod carrier to pro-duce one panel per team each day.

Indoor work

panels run in strips around the buildingand, when the design calls for a punchedwindow, column covers provide the verti-cal elements between windows and atthe buildings corners.

Panels are fastened to the building invarious ways, all based on the same gen-eral theme. For each panel, there are twodead-load bearing points. Ideally theseare in the panels upper half in pocketsthat put the bearing point near the pan-els lateral center of gravity so that, whenfirst mounted, the panel hangs in its fin-ished position on the building. Lateralconnectors that provide resistance towind and seismic loads and that stabilizethe panels are located in various spotsbelow the dead-load connections. On atypical 30-foot-long panel there might bethree lateral load connectors along thefloor line and five more across the bot-tom of the panel.

Column covers (in punched windowbuildings) typically bear on the spandrelpanel below and are shear-connected tothe panel above. Lateral support is pro-vided by connections to the building col-umn behind the cover.

Before installing the panels, weldersgo around the building and weld 4-x9-inch steel bars onto the building frame ator near the supporting building columns. Thesebars, two for each panel, serve as the dead-load sup-port brackets. Typically, welders will attach thesebrackets to steel angles that are embedded into thefloor slabs, although in some cases the brackets arewelded to steel or concrete columns. These heavysteel brackets protrude from thebuilding frame and have a verticalthreaded adjustment pin, which willsupport the dead load of the panel.

When there is a tower crane avail-able, panels go up much morequicklyGalassi estimates that acrew can complete 12 to 18 panelsper day with a tower crane versuseight to 10 per day with a mobilecrane. The crews at this stage arecomposite crews of welders andmasons. The masons set the panelsand handle any brick that needs to beplaced onsite.

There are pockets built into theback of each panel for the dead-loadconnection. The steel bearing platefor the dead-load connection is inte-grated into the reinforcing steel sys-tem vertically and horizontally. Pan-els are set onto the dead-load pinsand workers on the building interiorprecisely adjust the position. There

are several inches of adjustment possible on the pan-els, both horizontally and vertically. Once the panelshave been inched into precise positions, the entireconnection is welded together to solidly link the pan-els and the building frame. Lateral-load connectorsalso are adjusted and welded. Crew members caulk

the joints between the panels with acolor that matches the mortar. Theythen sand the caulk to give it thesame appearance as the mortar.

Most panel projects include somelaid-in-place brick. Often these arelaid near ground level, where thejoints between panels would bemore noticeable.

DrawbacksPrefabricated brick panels are not

right for every job. Some architec-tural designs simply dont lendthemselves to panelization. And onbuildings with straight flat walls,wood frames or fewer than threestories, field-laid brick usually arethe most economical alternative.

Historically, very few problemsarise during construction or after-wards with prefabricated brick pan-els. Occasionally there may be aproblem with inadequate stiffness in

Mutual Materials produced special 45-degree knife-edge bricks whichmatched the incorporated precast elements on this Microsoft building.

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The Redmond, Wash. Town Centercomplex used brick panels made upof a blend of three colors of brick.The color blend ratio varies frombuilding to building.

one of the supports, so that it fails when the panelsdead load is applied. There have been a couple ofcases of rust after several years that caused brick tospall but these were due to a poorly constructed con-nector pocket that allowed water to pool on the con-nector. To guard against this, many connectors noware made from galvanized or stainless steel.

Negotiating for qualityA successful brick-panel project requires the con-

tractor to be involved from the very start. When Ifirst meet with the owner and architect, I give them aprice based on producing and placing panels with nowater drainage system or insulation, says Galassi.Then he works with them to develop a system thatprovides the look the architect wants and meetsthe structures needs in the most economical way.This includes a drainage system, insulation, vaporbarriers and fire sealant.

Sample panels usually are constructed in the pro-jects early stages so that the architect knows howthe building panels will look. Often several differentpanels will be made with different ratios of brick col-

ors until everyone is satisfied with the results. Galas-si stresses that organization, communication and co-operation are critical. Because the panels are builtoffsite, miscommunication can result in serious prob-lems at delivery.

Prefabricated brick panels offer many advantagesfor certain types of buildings. Currently the only com-panies in the United States that produce brick panelson a regular basis are Barkshire, Pardue and Vet-O-Vitz. Although there are other contractors who haveused this construction system, and others who areinterested, they hesitate from a lack of knowledgeand confidence. And, as with any new method, thereis resistance from owners and building departments.Despite the difficulties, the masonry industry wouldbenefit from expanding the use of this system. JeffLeonard, Leonard Masonry Inc., St. Louis, currentlyis trying to get into the panel business. He feels pan-els will be competitive with precast concrete, whichhe has seen take a large share of the jobs that oncewould have been masonry. Masonry contractorsarent needed on every job, like plumbers and elec-tricians, he says, so we better start looking at newways to do things.

Publication #M99C022Copyright 1999, The Aberdeen Group, a division of Hanley-Wood, Inc.All rights reserved