This section examines the construction materials of the foundations and walls of the buildings within the Historic District. Roofing materials were discussed above, in the Roof section.
A structure looks best in the materials with which it was originally designed and built. If properly maintained, these materials will last for many years. Resurfacing or obscuring original material, including painting previously unpainted surfaces, should be avoided.
Materials - Masonry
Masonry includes brick, stone, terra cotta, concrete, stucco, tile, and mortar. Color, texture, mortar joints, and masonry patterns help to define a building's character.
Problems Typical to Masonry
If properly maintained, masonry can last for centuries. On the other hand, these extremely durable building materials can be seriously damaged by improper maintenance and repair procedures. Some problems may include the following:
Cracks, whether vertical or diagonal, may indicate serious structural problems. These cracks are often found over building openings where there has been movement or wood deterioration.
Loose or sandy mortar indicates that the mortar composition has
broken down or that the mortar has been washed away by the weather.
Missing or spalling masonry can be caused by trapped moisture in brick or stone where the freeze-thaw cycle pops out pieces of the masonry. This problem can also result from poorly fired bricks intended for interior walls being exposed to the weather. Such conditions occur when buildings are torn down and adjacent walls are exposed or when interior brick was used to construct the rear or side walls.
Poor repairs includes patches made with bricks that do not match in size, type, or color. Poor repointing can also make repairs visually unacceptable. Inappropriate mortar, such as Portland Cement, can also cause damage to bricks. Some buildings in Fredericksburg have had to be stuccoed or painted when the hard shell of their bricks was destroyed by sand blasting.
Damp masonry results from leaky roofs, gutters, or downspouts; poor site drainage; or a condition known as rising damp. Rising damp occurs when moisture is drawn up from the ground, through the masonry, by capillary action.
Efflorescence occurs when there is excessive moisture in a masonry
wall. When the water evaporates, it leaves salts, causing a white haze
Maintenance and Repair
1. Removing or radically changing masonry features will diminish a building's character. Retain masonry features that define this character such as walls, brackets, railings, cornices, window surrounds, pediments, steps, and columns. It is also important to retain mortar joint size and tooling; the size, texture, and pattern of the masonry units; and the color of the masonry.
2. Prevent water damage to brick and mortar as follows:
Maintain roofs, gutters, and downspouts in good repair and ensure
flashing is watertight.
Ensure ground slopes away from walls to prevent water from gathering at their base. If there is excessive ground water around a structure, install drain tiles.
Prevent rising damp by applying slate or other impervious material just above the ground level to create a dampproof course. A knowledgeable preservation architect or engineer will be required to advise on this type of treatment.
Avoid non-historic waterproof or water-repellent coatings. These materials often trap moisture inside the masonry, causing additional problems.
3. Cleaning requires knowledgeable persons who understand masonry as well as available acceptable cleaning agents. Improperly cleaned masonry can result in chipped or pitted bricks, washed out mortar, rounded edges on bricks, or a residue of film on the masonry. As a consequence, cleaning should only be undertaken to arrest deterioration or to remove heavy soiling. Clean masonry as follows:
Clean unpainted masonry with the gentlest means possible. Use a low pressure water wash (600-1000 pounds per square inch) with detergents and natural bristle brushes.
Test the cleaner on a small inconspicuous part of the building. Observe the test a sufficient period to determine the gentlest possible cleaning method. Some old bricks are too soft to clean and can be damaged by detergents and water pressure.
Avoid needless cleaning of masonry in order to obtain an appearance that is new.
Avoid chemical methods that damage masonry or leave a chemical residue on the masonry. Do not clean marble or limestone with acid cleaners.
Avoid cleaning in freezing conditions when using water or water-based chemicals.
4. Repair masonry by repointing deteriorated mortar joints. Masonry walls may not have to be repointed for 50 years, but do require special attention when this task is accomplished. Repoint masonry as follows:
Remove deteriorated mortar with a chisel to a depth of at least a half or three quarters of an inch. Do not use electric saws or hammers as these will damage the masonry.
Duplicate the mortar in strength, composition, color, and texture. Mortar in older brick buildings has a high lime and sand content while in newer buildings the lime content would be much less and the Portland Cement content more. It is important not to repoint with mortar which is stronger than the original mortar. Brick expands and contracts with freezing and heating. If Portland Cement is not used in the correct proportions, the mortar will not move to relieve the stress and bricks will crack, break, or spall. Do not repoint with synthetic caulking compound.
Duplicate old mortar joints in both width and profile.
5. Repair damaged masonry features, as follows:
Patch, piece in, or consolidate masonry components to match the original instead of replacing an entire feature.
Repair stucco by removing loose material and patching with new material that is similar in composition and texture.
Use epoxies to repair broken stone or carved details. Such materials, however, should be applied by skilled craftsmen.
6. Painting and waterproofing masonry is sometimes necessary as a preservation treatment. These tasks should be undertaken, as follows:
Leave masonry unpainted, as a general rule, if it has not been painted previously. Water repellent coatings should be considered as a last resort if repointing and drainage problem corrections have failed to arrest water penetration.
Remove only damaged or deteriorated paint from historically painted masonry, by hand scraping with great care prior to repainting. Paint that has adhered strongly to masonry should be left and painted over rather than risking damage to the masonry by breaking the bond.
Clean dirty masonry, prior to repainting, with a low-pressure water wash. Avoid sandblasting, high-pressure water, or caustic solutions, as these will damage bricks.
Allow masonry to dry for at least fourteen days prior to repainting.
Prime with an appropriate masonry primer that is also compatible with the last layer of paint applied to the building.
Repaint with an appropriate masonry paint system.
7. Continue to evaluate the overall condition of masonry elements to determine when maintenance and repairs are needed.
Materials - Wood
The flexibility of wood has made it one of the most common building materials throughout the nation's building history. It has been used to build elements of virtually every building in Fredericksburg and is found in such features as windows, shutters, cornices, brackets, columns, storefronts, doors, and decorative features as well as in siding and shingles.
Typical Problems with Wood
Cracked or warped boards can result from weather, aging, the direction it was originally sawn, or stresses placed upon it.
Cracked peeling, or blistered paint is found where moisture is present, where paints are incompatible, or where surfaces have not been prepared properly prior to painting.
Rotted wood occurs where there is excessive moisture, often around gutters, downspouts, plumbing, and flashing. Unventilated foundations can also cause rot.
Infestation can be an extremely serious problem as termites and powder-post beetles damage a building's wood, including its structural frame.
Maintenance and Repair
1. Inspect and evaluate wood surfaces for signs of excessive water, deterioration, and infestation. Identify and address causes of wood deterioration. Keep painted surfaces primed and painted to prevent water infiltration and rot. Maintain wood materials as follows:
Eliminate infestation with appropriate poisons.
Remove vegetation that grows close to wood surfaces.
Eliminate moisture problem areas by maintaining roofs, gutters, and downspouts in good repair. Secure or replace loose or deteriorated flashing. around a building's foundation.
Maintain caulk in good repair where water can penetrate a building, including the junction of dissimilar materials, construction joints such as siding and cornerboards, and around openings like windows and doors. Remove old caulk and dirt before recaulking. Do not caulk under individual siding boards as this will seal the building too tight and cause additional moisture problems.
2. Properly prepare wood surfaces prior to painting to ensure a sound, long-lasting paint job. Prepare surfaces, as follows:
Clean the surface to be painted with a household detergent and water to ensure paint will adhere properly. Rinse thoroughly. Allow sufficient time for the wood to dry completely (at least two weeks of dry weather is recommended) so paint will bond.
Remove loose paint to the next sound layer using the gentlest
means possible such as hand scraping and sanding. Avoid destructive paint
removal methods such as open flame torch, sandblasting, or water blasting.
In addition to harming historic surfaces, open flames can potentially remove
the historic building in its
Electric heat guns and heat plates are useful when additional paint removal is required such as on decorative wood features or where paint has built up excessively such as on sills and porch rails. Extreme care must be taken to avoid fires.
Chemical strippers can supplement the above techniques. These should be carefully used according to directions and the chemicals thoroughly neutralized after use to ensure subsequent paint adhesion to the wood.
3. Use an appropriate paint system (primer and paint) to achieve lasting results. Older buildings, for example, have usually been painted with oil-based paint. An oil-based paint can be reapplied, but such paints do not have the longevity they once had because they are no longer allowed to be manufactured with lead. Latex paint may be preferable, but will not adhere to chalked oil paint and will also shrink as it dries, pulling off any old oil paint underneath. If paint type is going to be changed (from oil to latex), the surface must be primed in its entirety with an oil-based primer before the latex topcoat is applied.
4. Repair rather than replace wood elements. It is often possible to patch, piece, or consolidate rotted wood parts rather than replace an entire element. When repairs are required, they should match the original in all its physical and visual characteristics.
5. Wood elements should be replaced only when rotted beyond repair. Replace only the deteriorated wood rather than trying to reconstruct a building with new material to achieve a uniform appearance. Replacement elements should match the original in all their physical and visual characteristics. Replacement should be accomplished as follows:
Replication of a missing feature should occur if physical and
photographic evidence is available upon which to base the design of the
missing element. Elements on other buildings in the area is not sufficient
evidence upon which to base a replication.
Reestablishment of a missing feature may occur if there is no
physical or photographic evidence available upon which to base its design.
This new feature, however, must necessarily be a reinterpretation of this
historic feature rather than a copy. This new element should also complement
the existing building elements in its size, scale, and
6. Continue to evaluate the overall condition of wood elements to determine
when maintenance and repairs are needed.
In the nineteenth century, the variety of metals used in building construction expanded considerably. Cast iron, steel, pressed tin, copper, aluminum, nickel, bronze, galvanized sheet iron, and zinc all appeared at various times in different architectural features.
Aluminum shows up in many storefronts as well as in storm windows.
Iron or steel can be identified with a magnet and are found in everything from fences to roofs.
Copper is used on some roofs as well as in gutters and downspouts.
Other metals can be identified by experienced professionals.
Typical Problems with Metals
Corrosion is the chemical reaction of metal with oxygen or other elements. It may occur throughout the metal or only at stress points.
Dissimilar metals that are in contact with one another may produce an electrochemical action that will result in corrosion.
Moisture and pollutants will react with exposed metals and result in corrosion.
Mechanical breakdown of metals can result from abrasion (erosion of the metal), fatigue (from too much stress), fire, and connection failures (overloaded, fatigued, or corroded bolts, rivets, pins, and welds).
Maintenance and Repair
1. Inspect and evaluate metal surfaces for corrosion and mechanical breakdown. Eliminate excessive moisture by maintaining roofs, gutters, and downspouts in good repair. As appropriate for the material, keep surfaces painted or protected with appropriate finishes.
2. To prepare metal surfaces for repainting, clean gently by hand scraping or wire brushing to remove loose paint. Paint removed to bare metal is not required, but removal of all corrosion is essential. Prepare metal surfaces as follows:
Hard metals such as cast iron and iron alloys can be cleaned with low-pressure, dry grit blasting (80-100 pounds per square inch), if gentler means to remove old paint and corrosion are unsuccessful. Protect adjacent wood or masonry surfaces from the grit.
Soft metals such as copper, lead, and terneplate should not be cleaned with grit, but with chemical or thermal methods.
Apply rust-inhibiting primer immediately after cleaning.
Avoid removing the patina of metals, such as occurs on bronze or copper, that provide a protective coating.
3. Repaint metal surfaces, as follows:
Remove all loose and peeling paint and corrosion.
Prime and paint cleaned surfaces with rust-inhibiting primer and paint that are appropriate to the material.
4. Repair of metal elements on a building must often include replacement because of the nature of these materials. Repairs should be accomplished as follows.
Stabilize metals (to arrest corrosion) and preserve them by painting or coating.
Replace metals deteriorated beyond repair with like metals that match the original in all physical and visual characteristics.
Introduce new materials such as aluminum, fiberglass, or wood only if it is not technically or financially feasible to construct in the original material. The new material should match the original in all physical and visual characteristics.
Avoid placing incompatible metals together without a separation material that will prevent corrosion from dissimilar metals.
5. Continue to evaluate the overall condition of architectural metals to determine when maintenance and repairs are needed.
Materials - Synthetic Siding
The historic character of a building is a combination of its design, age, setting, and materials. The exterior walls of a building are one of its most visible aspects and can include clapboards, shingles, board and batten, brick, stone, and so on. Over the years, however, a series of home improvement businesses have convinced some building owners to add new siding materials to their buildings. These materials have changed over time, but have included asbestos, asphalt, aluminum, and vinyl. These synthetic sidings have often been manufactured to look like other siding materials like bricks or wood.
Typical Problems with Synthetic Siding
Loss of historic integrity occurs when original materials are removed or covered with materials from a later period of construction.
Altered visual appearances occur when siding such as wood or masonry is covered with a synthetic material. Even if wood siding is covered with aluminum or vinyl that is manufactured to look like wood, there is usually a difference in the board width which can alter a building's character. There also occurs a change in the wall plane that becomes evident where the synthetic siding abuts windows and doors, often sinking these openings into the wall.
Loss of architectural detail occurs when brackets and decorative elements are sawn off to facilitate installation of the synthetic siding (which requires a flat surface to which it can be nailed).
Moisture can build up in the cavity between the original wall and the new material because the synthetic material creates a vapor barrier. The small vents in the various types of siding are inadequate to avoid this problem.
Inspection of building components is prevented when synthetic
siding covers walls that may be deteriorating and need attention.
1. Do not apply synthetic siding over existing original siding or remove old siding to apply new synthetic siding.
2. Consider removing synthetic siding to reveal a building's historic character and restore original building material, as applicable.
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