Conservation and restoration of lighthouses
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.
Any buildings that remain intact and in their original location are historically important to the relationship and usage of the lighthouse.
[4] Evidence of paint degradation include crazing, cracking, peeling between coats, blistering, and wrinkling.
Original paint was made of lead and tended to withstand harsh conditions while still protecting the structure.
The required use of National Historic Preservation approved paints has proved difficult as they do not work well with the lighthouse structure's original materials [5] Most repainting projects will have to begin with removal of the original base coat, followed by a thorough surface cleaning to remove impurities, then ended with a complete repainting of the structure.
The composition of stucco has changed significantly over the years and may require laboratory analysis to determine the makeup.
[4] Most of the problems with stucco arise from prolonged contact with water or moisture which breaks down the structure of the particles and binder.
As with most preservation, gentle cleaning of the surface can help remove dirt and impurities and inhibit further deterioration.
Damage to masonry is primarily caused by water, salt accumulation, expansion and contraction, abrasion, poor ventilation, and inappropriate cleaning techniques (ex.
Masonry may show many signs of deterioration to include: bulges, cracks, efflorescence, erosion, flaking, sloping or uneven settlement, mold or mildew, missing stones or bricks, condensation buildup, and blistering.
Soaking is a process where the masonry undergoes a prolonged exposure to misting water to remove dirt.
Some signs of decomposition include cracking, bulging, holes, peeling paint, leaning of the structure, gaps between joints, and exposed bare wood.
Some complications from wood deterioration can be solved through tight fitting seals around windows and doors, gutter systems, caulking of seams and joints, and sloping away of decking from the structure.
Regular cleaning of the surface may also help reduce accumulated residues on the wood thereby prolonging its usable life.
Concrete can mean a variety of compositions including sand, gravel, and crushed stone bound with lime or cements.
A protective coating of either paint, stucco, or lime-mortar-wash is typically applied to concrete lighthouses as a layer of defense from external elements.
[9] A majority of the lighthouse interiors' issues stem from moisture, condensation, neglect, or inappropriate treatments.
Neglect causes deterioration due to lack of cleaning, regular maintenance of windows, stairs, floors, or painting.
[7] Doors and windows should be repaired with care taken not to damage historic moldings and entry features of the lighthouse.
[7] The lantern is the large round glass structure, that houses the lens, located at the top of the lighthouse.
Any conservation or restoration processes should keep in mind that the lantern, ventilation shafts, and lens should not be obstructed in any way.
[11] To secure the prisms of the lens a compound of calcium carbonate, lead, and linseed oil, called litharge, was used.
If fine or non-abrasive particles are observed, a soft cotton cloth lightly wetted with distilled water may be used to gently clean the surface.
Any residue polish from the past should be removed using a diluted detergent solution and a soft brush or cotton swab.
[16] Past disasters include being "swept away by tsunamis, destroyed by hurricanes, toppled by erosion, gutted by fire, even targeted by weapons of war.
"[16] Storms and hurricanes bring heavy rain, strong wind, rising surf, and large waves.
These result in broken windows, flooding, structural damage to the buildings, erosion of the surrounding land, and more.
The assessment includes touring the area and building for safety hazards, such as broken glass, down power lines, and mass erosion of land.
[18] The U.S. Coast Guard’s Civil Engineering Unit is responsible for the maintenance and preservation of the St. Simons Island Lighthouse.
One of their projects was the replacement of the panels in their third-order Fresnel lens, while also conserving existing lanterns considering the limited budget available.
