Formstone is a type of stucco [1] commonly applied to brick rowhouses in many East Coast urban areas in the United States, although it is most strongly associated with Baltimore. As a form of simulated masonry, Formstone is commonly colored and shaped on the building to imitate various forms of masonry compound, creating the trompe-l'œil appearance of stone.
Formstone was patented by Lewis Albert Knight of the Baltimore-based Lasting Products Company in 1937, [1] [2] [3] although a similar product named Permastone had been invented in Columbus, Ohio, eight years prior. [3] The name Formstone was actually a brand name used by Knight. [1] Permastone, Fieldstone, Dixie Stone, and Stone of Ages were names used for a product similar to Knight's Formstone, particularly in other cities. [4]
Formstone was used widely in Baltimore city. [3] [5] Formstone was primarily used in remodeling but could also be used for new construction. [6] Film director and Baltimore native John Waters described Formstone as "the polyester of brick." [7] Baltimore became the “Formstone capital of the world." [6]
The Baltimore-based Lasting Products Company, the parent company of Formstone, was later known as the Formstone Co. Not long after Formstone was invented, the Lasting Products Company disbanded during World War II. When business resumed, the majority of buildings faced in Formstone were single-family homes. It was not long until rowhouse homeowners in more urban and working-class areas of Baltimore wanted the clean and polished look of Formstone. The company opened successful franchise locations in various cities across the United States but Baltimore was the epicenter of the Formstone phenomenon. [8] The company provided all of the tools and materials needed to complete a Formstone project and trained registered contractors on how to sell and apply Formstone. [6] There were many competitors in the 1950s and 1960s, some with salesmen who advertised different materials under the Formstone product name. The competitors used a simulated stone product similar to Formstone but with different variations in patterns, colors, and application.
Formstone’s popularity came from the promise that it was inexpensive, maintenance-free, and more energy-efficient. It also gave Baltimore rowhouses a more modern look. [9] A 1950 advertisement for Formstone revealed the “secret of its popularity: weatherproof and insulating forever; first cost is the last; no upkeep or repair…lasting beauty for exteriors or interiors; tried and proven; fully guaranteed.” [3] Formstone was meant to be a maintenance-free alternative to the low-quality brick that many early Baltimore rowhouses were constructed with. These brick buildings required a lot of upkeep and frequent painting. But for the cost of three paint jobs, Formstone could be applied to the building’s exterior and eliminate much of the effort to maintain the exterior brick. [8]
At the height of its popularity in the 1950s, Formstone was a sign of wealth and stability in the working class neighborhoods of Baltimore. But the longevity of Formstone was not living up to the company’s promises and the Formstone Co. went out of business in the late 1960s. [10] Aluminum and vinyl siding, much cheaper ways to weather-proof buildings, became more popular and contributed to the decline of Formstone and other simulated stone products.
Formstone, described as "[a]n odd architectural fad" by urban design critic John King, appeared in San Francisco in the 1930s and '40s. [11] While not particularly common, it is still found around the city. Like San Francisco, in Washington, DC, the same debate over whether it is historic or should be removed continues where it was used to mimic granite and other stone in a rather historic city famous for real stone buildings. [12]
Formstone is mixed on-site and applied directly to a building’s exterior. Knight wanted to provide a process for that used the tools of masonry and cement finishers so they could easily follow the application process. [6] Formstone is applied in three layers, anchored by a perforated metal lath attached to the underlying brick with nails. [3] Galvanized mesh was used in many instances to reduce the likelihood of rusting. The three layers are cement-based concrete. The first layer of cement mortar is 3/8” to 3/4” thick and it is scored before it dries. The second layer is between 1/4” and 3/8” thick. The top layer, or finish layer, is also between 1/4” and 3/8” thick and is applied while the second layer is still plastic. While the finish layer is still wet, it is hand-sculpted into the shape of stones. [6] The finish layer contains the coloration used to imitate stone and is textured using waxed paper and an aluminum roller. [3] Mica could also be sprayed on the surface to give the Formstone a sparkly, clean look. Mortar joints are then scored into the top layer to mimic natural stone construction. [6] [3]
One major failure of Formstone is that the metal lath holding the faux stone to the building can start to pull away from the brick. Without a strong bond between the Formstone and the underlying brick, moisture is allowed to enter between the two materials and become trapped. Applying Formstone to rowhouses constructed with early brick from the eighteenth and nineteenth centuries caused many problems. This early brick was soft, porous, and susceptible to deterioration. [13] Formstone prevents the historic brick from breathing and the accumulation of moisture causes cracks to form. [14] This moisture combined with the freeze-thaw cycle can damage the Formstone material and, if left uncorrected, can lead to further deterioration and penetration of moisture into the underlying brick. [15] This can lead to spalling, efflorescence, and loosened mortar joints on the brick façade. [13] Formstone is only waterproof as long as it does not deteriorate and separate from the wall.
Another preservation issue stems from the application of the Formstone. When it was applied to the exterior façade of a building, historically significant architectural features were often covered up or removed. Features such as cornices, belt courses, lintels, and sills were not only decorative, they were necessary for diverting water away from the building, leading to even more damage from moisture intrusion. [16]
When a building owner decides to remove the Formstone, historical fabric and significant features can be damaged during this process. When the metal lath is removed, it leaves the original poor quality brick surface pock-marked with holes in the mortar joints. This requires cleaning and repointing of the brick, and sometimes replacement of severely damaged brick, which can be very expensive. [3]
There is debate over the historical significance of Formstone. Because it was usually applied to buildings long after their initial construction, Formstone is viewed by some as an inauthentic addition that detracts from the historical significance of the building. [8] But some historic preservationists, architects, and citizens, particularly in the city of Baltimore, argue that Formstone has acquired its own historical significance as it has become a part of the Baltimore landscape and is representative of the history and evolution of the city’s working-class neighborhoods.[ citation needed ]
A brick is a type of construction material used to build walls, pavements and other elements in masonry construction. Properly, the term brick denotes a unit primarily composed of clay, but is now also used informally to denote units made of other materials or other chemically cured construction blocks. Bricks can be joined using mortar, adhesives or by interlocking. Bricks are usually produced at brickworks in numerous classes, types, materials, and sizes which vary with region, and are produced in bulk quantities.
Masonry is the craft of building a structure with brick, stone, or similar material, including mortar plastering which are often laid in, bound and pasted together by mortar. The term masonry can also refer to the building units themselves.
Plaster is a building material used for the protective or decorative coating of walls and ceilings and for moulding and casting decorative elements. In English, "plaster" usually means a material used for the interiors of buildings, while "render" commonly refers to external applications. The term stucco refers to plasterwork that is worked in some way to produce relief decoration, rather than flat surfaces.
A terrace, terraced house (UK), or townhouse (US) is a kind of medium-density housing that first started in 16th century Europe with a row of joined houses sharing side walls. In the United States and Canada these are sometimes known as row houses or row homes.
Stucco or render is a construction material made of aggregates, a binder, and water. Stucco is applied wet and hardens to a very dense solid. It is used as a decorative coating for walls and ceilings, exterior walls, and as a sculptural and artistic material in architecture. Stucco can be applied on construction materials such as metal, expanded metal lath, concrete, cinder block, or clay brick and adobe for decorative and structural purposes.
Siding or wall cladding is the protective material attached to the exterior side of a wall of a house or other building. Along with the roof, it forms the first line of defense against the elements, most importantly sun, rain/snow, heat and cold, thus creating a stable, more comfortable environment on the interior side. The siding material and style also can enhance or detract from the building's beauty. There is a wide and expanding variety of materials to side with, both natural and artificial, each with its own benefits and drawbacks. Masonry walls as such do not require siding, but any wall can be sided. Walls that are internally framed, whether with wood, or steel I-beams, however, must always be sided.
Lath and plaster is a building process used to finish mainly interior dividing walls and ceilings. It consists of narrow strips of wood (laths) which are nailed horizontally across the wall studs or ceiling joists and then coated in plaster. The technique derives from an earlier, more primitive process called wattle and daub.
In chemistry, efflorescence is the migration of a salt to the surface of a porous material, where it forms a coating. The essential process involves the dissolving of an internally held salt in water, or occasionally in another solvent. The water, with the salt now held in solution, migrates to the surface, then evaporates, leaving a coating of the salt.
Repointing is the process of renewing the pointing, which is the external part of mortar joints, in masonry construction. Over time, weathering and decay cause voids in the joints between masonry units, usually in bricks, allowing the undesirable entrance of water. Water entering through these voids can cause significant damage through frost weathering and from salt dissolution and deposition. Repointing is also called pointing, or pointing up, although these terms more properly refer to the finishing step in new construction.
Lime plaster is a type of plaster composed of sand, water, and lime, usually non-hydraulic hydrated lime. Ancient lime plaster often contained horse hair for reinforcement and pozzolan additives to reduce the working time.
Plasterwork is construction or ornamentation done with plaster, such as a layer of plaster on an interior or exterior wall structure, or plaster decorative moldings on ceilings or walls. This is also sometimes called pargeting. The process of creating plasterwork, called plastering or rendering, has been used in building construction for centuries. For the art history of three-dimensional plaster, see stucco.
Lime mortar or torching is a masonry mortar composed of lime and an aggregate such as sand, mixed with water. It is one of the oldest known types of mortar, used in ancient Rome and Greece, when it largely replaced the clay and gypsum mortars common to ancient Egyptian construction.
Stone veneer is a thin layer of any stone used as decorative facing material that is not meant to be load bearing. Stone cladding is a stone veneer, or simulated stone, applied to a building or other structure made of a material other than stone. Stone cladding is sometimes applied to concrete and steel buildings as part of their original architectural design.
Structural dampness is the presence of unwanted moisture in the structure of a building, either the result of intrusion from outside or condensation from within the structure. A high proportion of damp problems in buildings are caused by ambient climate dependent factors of condensation and rain penetration. Capillary penetration of fluid from the ground up through concrete or masonry is known as "rising damp" and is governed by the shape and porosity of the construction materials through which this evaporation-limited capillary penetration takes place. Structural damp, regardless of the mechanisms through which it takes place, is exacerbated by higher levels of humidity.
Damp proofing in construction is a type of moisture control applied to building walls and floors to prevent moisture from passing into the interior spaces. Dampness problems are among the most frequent problems encountered in residences.
Masonry veneer walls consist of a single non-structural external layer of masonry, typically made of brick, stone or manufactured stone. Masonry veneer can have an air space behind it and is technically called "anchored veneer". A masonry veneer attached directly to the backing is called "adhered veneer". The innermost element is structural, and may consist of masonry, concrete, timber or metal frame.
A weep, a weep hole, or a weep-brick is a small opening that allows water to drain from within an assembly. Weeps are located at the bottom of the object to allow for drainage; the weep hole must be sized adequately to overcome surface tension.
An external wall insulation system is a thermally insulated, protective, and decorative exterior cladding procedure involving the use of expanded polystyrene, mineral wool, polyurethane foam or phenolic foam, topped off with a reinforced cement based, mineral or synthetic finish and plaster.
Casa Vives is a historic building located in the Ponce Historic Zone in Ponce, Puerto Rico, across from the Plaza de Mercado de Ponce. The home was designed by Juan Bertoli Calderoni for Carlos Vives, a prominent local merchant and owner of Hacienda Buena Vista, and built by Carlos Milan. The home was built in 1860, in the neoclassical style, making it one of the first brick and mortar homes built in the city. It was added to the U.S. National Register of Historic Places on 13 February 2013. Architecturally, Casa Vives retains all seven aspects of integrity: location, design, setting, materials, workmanship, feeling and association.
The conservation and restoration of lighthouses is when lighthouse structures are preserved through detailed examination, cleaning, and in-kind replacement of materials. Given the wide variety of materials used to construct lighthouses, a variety of techniques and considerations are required. Lighthouses alert seagoers of rocky shores nearby and provide landmark navigation. They also act as a physical representation to maritime history and advancement. These historic buildings are prone to deterioration due to their location on rocky outcrops of land near the water, as well as severe weather events, and the continued rise of sea levels. Given these conditions preservation and conservation efforts have increased.
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