Plaster is a popular material used for interior wall finishes, known for its durability and timeless aesthetic appeal. When it comes to renovating older homes, it is not uncommon to encounter walls that are covered in horsehair plaster. This type of plaster was commonly used in homes built before the 1950s and is known for its unique mix of lime, sand, and horsehair fibers. However, as homeowners look to update their living spaces, they may wonder if it is possible to plaster over old horsehair plaster without removing it entirely. In this article, we will explore the advantages and challenges of plastering over old horsehair plaster.
Advantages of Plastering over Old Horsehair Plaster:
1. Time and Cost-Efficient:
One of the main benefits of plastering over old horsehair plaster is that it can save a significant amount of time and money compared to completely removing and replacing it. Removing horsehair plaster can be a labor-intensive task, requiring extensive demolition and disposal. By simply plastering over the existing surface, you can eliminate the need for any messy removal processes, thereby reducing both labor and disposal costs.
2. Retention of Architectural Features:
Older homes often boast unique architectural features, such as ornate moldings, medallions, or decorative plasterwork. Plastering over horsehair plaster allows for the preservation of these original details. By adding a new layer of plaster, you can hide any imperfections while still maintaining the character and charm of your home.
Challenges and Considerations:
1. Surface Preparation:
Before plastering over old horsehair plaster, it is crucial to prepare the surface properly. The existing plaster should be clean, stable, and free from loose debris or paint. Any loose or damaged areas should be repaired before applying the new plaster. In some cases, a bonding agent may be required to improve adhesion between the old and new layers.
2. Thicker Walls:
Plastering over horsehair plaster can add thickness to your walls. This is because each additional layer of plaster increases the overall thickness of the wall. While this may not be a significant concern in most cases, it is essential to consider how the new plaster will affect doors, windows, and electrical outlets.
3. Structural Integrity:
Old horsehair plaster, especially in older homes, may have experienced years of wear and tear. Before plastering over it, it is crucial to ensure that the existing plaster is structurally stable. Inspect for any signs of sagging, cracking, or moisture damage, as these issues can compromise the new plaster’s longevity. If there are extensive structural concerns, it may be necessary to address them before proceeding with plastering.
4. Plaster Compatibility:
It is essential to use a compatible plaster mix when plastering over old horsehair plaster. Traditional lime-based plasters are best suited for this purpose, as they allow for the necessary breathability and flexibility needed to work with older substrates. Proper mixing and application techniques should be employed to ensure a strong bond between the old and new plaster layers.Plastering over old horsehair plaster can be a viable option for updating the walls in your older home. It offers a time and cost-efficient alternative to complete removal, while still allowing for the retention of architectural features. However, it is crucial to address surface preparation, consider the impact on wall thickness, ensure structural integrity, and use a suitable plaster mix for a successful and long-lasting result. Consulting with a professional plasterer or contractor is recommended to ensure proper execution and to address any specific challenges your walls may present.