Replacing Historic Terra Cotta- TerraGlas

Damaged terra cotta on a historic building in Grand Rapids, MI

Replacing Historic Terra Cotta

Considered to be a durable, long-lasting architectural material, historical terra cotta can stand the test of time, including being exposed to the elements like inclement weather and even moderate earthquakes not to mention pollution. However, over time, these structures will require terra cotta replacement as part of the historic restoration process on a building.

New technology has led to the development of new materials and processes that can simplify the process of terra cotta replacement, which can lower the costs associated with historical restoration projects while ensuring that the historic terra cotta replacement is accurate and results in a beautiful structure for years to come. However, this type of replacement can still take considerable time and be costly. This does not have to be the result if you work with a partner that can provide cost-effective materials and products with shorter lead times, resulting in lower installation costs.

This blog post provides tips on how to repair terra cotta as well as replace individual terra cotta pieces and assemblies and how to determine which anchors and attachment strategies will keep the structure in place.

Terra cotta restoration by TerraGlas

Replacing Individual Terra Cotta Pieces and Assemblies

There are specific strategies that TerraGlas and Stromberg Architectural Products have found work well for replacing individual terra cotta pieces such as these described below:

• Cornice: This piece cannot simply be stuck on the corner of a building, but it must be placed in such a way to make sure that the water runs off of it and away from the structure as well as ensure that it does not compromise the building’s corner support system.
• Railings: These can be replaced and reattached using mortar or by using a process that threads a rod through the railings to then reattach to the building. The threading process is often easier to accomplish and provides a way to replace certain segments of the railing without having to remove the entire system.
• Wall facing: Wall facing can come off in various size pieces, some of which can be quite heavy if they were original terra cotta pieces. This can be a complex process of replacement in terms of having to fill in the missing wall facing or deciding to remove a larger portion to recover an entire wall with new terra cotta wall facing.
• Door and window surrounds: Since these are often found in large numbers on a building façade, it is important that any replacements closely match the other existing door and window surrounds that are still in good repair.
• Medallions: These are often highly ornamented and contain intricate details that may seem difficult to replicate if part of the design has worn away or completely deteriorated.

What to Think about with Terra Cotta Replacement

When replacing both individual pieces and assemblies, the most important aspects to focus on in the replacement of the terra cotta are the following components to ensure a uniform look when it is replaced:

• Color match: This can be challenging to accomplish with historic terra cotta because some of the clays are no longer available so firing an exact match may not be possible.  Yet, technology has offered new ways to match color in the lab and develop a match that can blend across individual terra cotta pieces and terra cotta assemblies.
• Detail match: Over time, the details on terra cotta can fade as the terra cotta clay shrinks. That makes casting an exact match with the same details challenging. However, terra cotta replacement specialists can reproduce details even from photos or what is left of the terra cotta.
• Materials: More materials are available that provide a viable terra cotta replacement solution, including those made with fiberglass or concrete. New types of materials like TerraGlas® are offering a lightweight, strong alternative to other types of terra cotta materials. Typically half the weight of traditional terra cotta, this means that it is easier to install with less installation time as well as decreased equipment and installation costs.
• During the replacement process, other strategies should be employed that consider what caused the terra cotta to deteriorate in the first place so that the risk of future damage to the terra cotta repairs can be minimized. This means waterproofing and reducing any water pathways onto the terra cotta as well as looking at the building’s structural integrity and making any necessary structural repairs.

The seasoned team of terra cotta specialists at TerraGlas has the expertise, technology, and experience of working on historic restoration projects to help address each of these components.

Anchors and Attachment for Terra Cotta Replacement

To ensure that the terra cotta replacement pieces or terra cotta replacement assemblies stay in place for the long term, anchors and attachments are an important consideration. For example, terra cotta assemblies that attach to a framing system should only use stainless steel screws, adhesives, or hangers. Large terra cotta units often require flex anchors while smaller terra cotta pieces are cast with straps, inserts, or wires in place to facilitate attaching them to the building by hand.

Whatever you choose to do in terms of anchors and attachment strategies for the terra cotta replacement, it is important to remember that you must ensure that it is properly secured as even the newest type of terra cotta materials can be heavy and injure or potentially kill someone if it falls on them. No building owner wants a cornice or window surround falling on someone.  The best approach is to try and attach the terra cotta in the same way that it was originally attached. At the same time, you don’t want any of the anchors to be visible as this takes away from the aesthetic appeal of the historic restoration. This makes anchoring and attachment a critical part of the terra cotta restoration process and why TerraGlas can help with lightweight materials and a strategy that ensures the terra cotta replacement pieces are secure and stable.

A Terra Cotta Replacement Specialist

TerraGlas has the materials, knowledge, and experience to assist you with all types of historic terra cotta replacement projects. Our terra cotta products and terra cotta expertise already graces some of the nation’s most prestigious historical buildings and historic restoration projects. To get started or get more information on how we can help on your specific terra cotta replacement project, call us at 903.454.0904 or send an email to: [email protected].