Restoration and Preservation facts for
the Historic Landmark Property Owners

Basic of Brownstone and dealing with ThemIn

Basic of Brownstone and dealing with Them

In early 1900s, it was pretty much popular among the middle income groups and they used to give their buildings a catchy, special and distinguished look compared to that of others, with brownstone facade Restoration.

A prosperous urban middle class kept on looking for something more distinguished, reasonable and dependable than the usual brick facades in the first five decades of the 19th century. With marble, granite, and limestone being way too costlier for shipping to Brooklyn, brownstone–a type of sandstone found in neighboring New Jersey and Connecticut—appeared as something much hassle-free for transportation. Much more affordable compared to limestone or granite, brownstone was quarried at a great pace from the two areas mentioned as developers engaged in a mad rush to meet the skyrocketing demand of infrastructures by New York City’s (NYC) exploding population.

Keeping the pricing issue and fast growing demand of homes in mind, Excelon Construction comes up with idea to restore authentic shape and beauty of historical brownstones. With the passage of time, as in the case of anything else, these things need to be taken care of, and worked on–something that may appear as a bit complicated or troublesome to handle in nowadays.

Routine Inspecting the Condition of Brownstone

The layered composition and high porosity means that brownstone deteriorates easily. Moreover, water, salt, freeze-thaw cycling, air pollutants, and similar factors can easily harm brownstones Restoration. And, the weather of New York City is highly suitable for the brownstones to suffer such blows.

Hence, a significant maintenance and repair become essential for many owners of historic buildings made of brownstones that have two basic characteristics—composition and structure–- which determine their appearance and performance.

Some is much harder and more durable than others. Before going for on any repairs, the condition of the stone should be surveyed, to easily detect the symptoms and possible causes of deterioration. Observations regarding the color, pattern, texture, and surface tooling of the brownstone, as well as previous repairs, can be very helpful to a conservator, architect, or contractor.

Problems related to brownstones can be avoided through proper maintenance, with a regular maintenance capable of preventing water infiltration and slowing down the rate of decay, cutting the repair and replacement costs.

What is rather treating is that improper cleaning can lead to more damage in minutes than the impact resulted from years of weathering. A gentle water wash or water and non-ionic detergent wash is something that can be attempted as the first cleaning method, without using use rough chemicals or applying abrasive methods, such as sand- or water-blasting. Loss of cohesion between sand grains as the binder deteriorates. Disaggregation at the surface of a stone can result in slow erosion of the surface and softening of tooling. Areas beneath surface crusts are also often disaggregated. Disaggregation often occurs in sheltered areas where moisture from other sources evaporates, in some cases from salt recrystallization.

Protection and Maintenance

A number of brownstone buildings, often dubbed as a testament to the layering of history, in NYC have undergone repair works, restoration, or remodeling at least once. Considering the age and quality of the remodeling, it may be seen as significant feature. Many brownstone owners today need to address the failures of old repairs. Old patches often fade over time, leading to a patchwork appearance to the building, with old stucco or cement starting to come loose. Even some areas may blister and detach from the substrate— something that occurs due to natural aging. However, in some cases, these are caused by inappropriate repair methods or installation.

A successful composite patch, irrespective of its size, or even a replacement of an entire façade, should be indistinguishable from the original stone, for a better outcome. In is also important that mortar joints in the new repair replicates the historic profile. Furthermore, one must keep in mind that repairs should not extend continuously between separate blocks of stone, since cracks can develop in the patches. Things we need to keep an eye on are: cleaning gutters regularly, maintaining roof, remove vegetation, fill up open joints, and maintain flashing and repointing. But sandblasting, high-pressure water blasting and other abrasive cleaning or paint removal techniques should never be used as they take a heavy toll on brownstones. Refacing can also come handy in some cases. But complete refacing should be avoided, however, when significant sections of original brownstone are intact and may be retained.Repointing with a way-too-hard mortar damage brownstone to a great extent as impermeable mortars force water. Repointing a building from has to be done from time to time.

It is not normally recommended that a brownstone be painted is generally not recommended as paint will adhere only to sound material. A thick paint build-up may lead to future damage by trapping moisture in the brownstone behind it. Surface finishing is achieved with acid-etching or rubbing stones to remove the thin outer film of pigmented cement binder and expose the shape, size, color and distribution of the aggregate grains on the surface of the a brownstone.

A proper repair mixture, a crucial ingredient for brownstone restoration, has the combination of a binder, aggregate, pigments, admixtures, and water. The most common repair mixture is a stucco-like mix consisting of cement and lime binder, crushed stone-sand aggregate, and small amounts of dry oxide pigments. Color matching is one also a key issue in case of creating a successful composite patch and it has to be based on a careful examination of the existing stone. Unlike composite repairs, which are generally applied only to decayed brownstones, brush-on cementations coatings are often randomly put on entire façades. They generally tend to hinder vapor transmission through the stone surface and hold water inside the stone, eventually causing it to disaggregate.

What we should also be aware of are waterproofing and water repellent coatings as they tend to trap moisture and migrating soluble salts. Both of them can result in the loss of brownstone surface through freezing or salt recrystallization.

Inappropriate Repair Methods

Many historic brownstone buildings in New York City have been repaired, restored, or remodeled at least once. In some cases, these old rehabilitations have become historic in their own right. Often they are a testament to the layering of history typical of old, urban centers. If your brownstone is in an historic district, you must check with your local landmarks board or commission before embarking on a restoration plan. Depending on the age and quality of the remodeling, it may be seen as significant feature. Many brownstone owners today need to address the failures of old repairs. Old patches often fade over time, resulting in a patchwork appearance to the building. Old stucco or cement may start to come loose, and some areas may blister and detach from the substrate. Sometimes, these failures occur as a result of natural aging, but sometimes they are caused by inappropriate repair methods or installation.

Inappropriate Mortars

Repointing with a mortar that is too hard or impermeable will damage brownstone. Impermeable mortars force water, which enters the masonry through joints and cracks, to collect in, and evaporate through, the stone itself rather than through the mortar joints. Moisture trapped in the masonry often damages the stone through salt crystallization or frost damage. In extreme cases, the masonry will spall completely, leaving protruding mortar. Similarly, composite patches that are too vaporing impermeable will result in deterioration of the natural stone. Pointing mortars should be sacrificial to the surrounding stone or brick, and owners should expect to repoint their building from time to time.

Cementations Coatings

Tinted cementations coatings are available under a variety of trade names and are one of the most common repair methods to avoid. Unlike composite repairs, which are generally applied only to deteriorated stone, brush-on cementations coatings are often indiscriminately applied to entire façades of sound and deteriorated stone. These coatings tend to hinder vapor transmission through the stone surface and hold water inside the stone, eventually causing it to disaggregate.

Painting

Painting brownstone is generally not recommended. Even paints that are vapor permeable may retard the passage of moisture and cause the underlying stone to deteriorate. This is especially true where cracks or open joints allow water to enter the masonry. A thick paint buildup may lead to future damage by trapping moisture in the stone behind it. Painting will not preserve decayed stone, since paint will adhere only to sound material.

Waterproofing

Waterproofing and water repellent coatings tend to trap moisture and migrating soluble salts. This may cause loss of stone surface through freezing or salt recrystallization. These coatings may also alter the color and reflective qualities of the stone. They also require regular and frequent reapplication, making this an expensive option for homeowners.

Harsh Cleaning

Sandblasting, high-pressure water blasting, and other abrasive cleaning or paint removal techniques damage stone and should never be used.

Step by Step Brownstone work in Pictures

Amid challenges including adverse structural, mineralogical, and environmental conditions of preserving a rich heritage of architectural brownstones, the buildings and homes at NYC and its neighborhood have raised hopes of taking up the challenge. Then again, the restoration of brownstone façades has grown into an industry. And aiming to contribute to the field, thus, facilitating the preservation or restoration of the beauty of brownstones, we are always ready to be by you.