Many older, natural stone structures have deteriorated surfaces, some of which cause aesthetic, life-safety, or structural concerns for their owners. Unlike brick or other façade materials, natural stone, particularly sandstone, tends to deteriorate. Due to this unique characteristic, the repair, restoration, and preservation of this material requires a thorough understanding and comprehensive evaluation.

Source of Deterioration

The first step in designing a repair project is to consider the source of the deterioration. Often, it is due to weather, climate, or environmental conditions. Deterioration may also be due to the forces of man, such as poor flashing design, improper construction, over-loading, or improper previous repairs.

The following are common sources of stone deterioration:

– Natural weathering
– Deterioration of joint material
– Lack of maintenance
– Improper previous repairs
– Poor copings and flashing details
– De-icing salts
– Improper coatings
– Location on the building
– Climate and weather, freeze-thaw damage

Types of Deterioration

The source of the deterioration is often responsible for the type of deterioration which the stone exhibits. Below is a short list of the common types of stone deterioration:

– Staining, biological growth, efflorescence, and sub florescence
– Cracking
– Spalling
– Delamination
– Exfoliation and scaling
– Disintegration and erosion, loss of naturally binding minerals

Repair Methods

Unit replacement is often the best way to achieve the closest match to the original appearance (assuming the original quarry can be located). Unfortunately, unit replacement is typically not feasible, either due to cost, logistics, or due to the construction of the building. For example, stones near the sidewalk that are deteriorated from de-icing salts may be 24 inches deep and carry the load of a multi-story building. When the cost of replacement outweighs the financial benefit, we must turn to restoration methods such as:

– Dutchman
– Custom patching
– Mechanical stitching
– Re-dressing
– Consolidation treatments and other coatings

Since the forces of man and nature affect each structure in different ways, the project team should install in-situ mockups to establish expectations for any repair program. It is important to understand that it can be difficult to make a permanent repair that will restore the original appearance of the building. For more information or for a detailed assessment of your situation, please contact Trisco Systems, Inc. at 419-339-3906.

When EIFS-clad structures begin to show signs of age and deterioration, building owners are left asking themselves what to do about it. Many architects and engineers are not educated on these systems and the knee-jerk reaction is to remove and replace the EIFS. However, not all system failures warrant replacement. Many times, less intrusive modifications can be made to the copings, flashings, sealants, or other components. There are options when it comes to EIFS repair.

In recent years, many EIFS manufacturers have made efforts to educate the market about how these systems can be restored and preserved. There are generally four levels of restoration:
1. Clean and recoat
2. Repair and refinish
3. Over-clad
4. Remove and replace

Replacement vs. Restoration Considerations
There are advantages and disadvantages to all scenarios. Often times, price is the determining factor and in many cases, restoring an existing system is more cost effective than replacement. It is important to consider what other factors are important to each situation when evaluating the type of repair to employ. Unlike new construction, most aging buildings are occupied structures. A restoration project will typically be quick, relatively quiet, and cause minimal impact to operations. A replacement project is much more intrusive and will likely disturb the occupants and users of the building as it can require sawing, grinding, cutting, and noisy demolition activities, not to mention longer project durations.

Deciding what to do
Determining which method is appropriate requires examination by an expert who has been trained in the diagnosis of EIFS failures. The most important factor is determining why the EIFS system is in distress. Often, this requires completing the building assessment process, whereby inspections may be required to understand what is happening beneath the surface. Remember, these projects are an opportunity. When restoring an EIFS system, there is the unique opportunity to use new colors and finishes that might rejuvenate the façade and increase the value of the building. This is especially true when modifications to the existing EIFS system can improve its function and prolong the service-life of the façade.

If you have an aging EIFS façade and want an opinion, please contact our sister company, Trisco Construction Services, at 419-339-9912. We would be happy to schedule a site visit to assess your situation and determine whether or not your project is a candidate for restoration.

In 2016, the Occupational Safety and Health Administration (OSHA) revised the standard which regulates the hazards associated with respirable crystalline silica in the work place. Though not entirely new, the revised standard has dramatically reduced the exposure limits for workers and has added many new requirements for employers. There are incredible costs associated with compliance, and
the implementation of these new standards is certain to shock the pricing structure in our industry. OSHA expects these new rules to prevent a significant number of worker deaths per year from silica-related diseases, the importance of which outweighs the cost.

What is respirable crystalline silica and what does it mean?

Crystalline silica is a mineral component that is found in many natural materials such as glass, ceramics, bricks, sand, concrete, stone, and mortar. Respirable crystalline silica (dust) – very small particles typically 100 times smaller than sand – is generated by operations such as cutting, blasting, sawing, grinding, drilling, sweeping, etc. Inhaling particles of airborne crystalline silica can cause diseases such as silicosis, lung cancer, chronic obstructive pulmonary disease, and kidney disease. In 2014, more workers actually died from
silicosis than fires or from being crushed in trenches.

What are the key provisions of the new standard?

1. The primary purpose is to significantly reduce workers’ exposure to respirable silica.
2. Employers must use engineering controls to limit this exposure. An example is utilizing a water delivery or vacuum system on any saws, grinders, chippers, or drills when they are used on silica containing materials. Localized exhaust ventilation and process isolation may also be utilized to remove the dust from the vicinity of the worker. If engineering controls do not work, employers must provide respirators for workers.
3. Housekeeping activities such as sweeping, dumping debris in dumpsters, etc. must be restricted.
4. Air monitoring must also be performed on a regular basis, both at the point of the “dust” generating procedure and at other areas within proximity to the work area.
5. The employer must make medical surveillance available at no cost to workers. This surveillance includes a cardio-pulmonary function test, a respirator fit test, a chest x-ray, a tuberculosis test, and others. Medical surveillance and record-keeping is the responsibility of the employer, not the employee.
6. A written Crystalline Silica Exposure Control Program must be developed and must be available to all employees. The plan must include several key components. Employers must provide air-monitoring and medical testing to provide proof that their Crystalline Silica Exposure Control Program is working.

What are the costs associated with compliance?
1. Implementation and training costs for educating employers and employees.
2. Air monitoring of work operations to establish baselines and the associated laboratory fees.
3. New equipment, modifications to existing equipment, and other costs associated with engineering controls.
4. Loss of productivity and efficiency due to changes in the way that work is performed.
5. Increased project durations and the associated general condition costs.
6. Medical surveillance costs (x-rays, monitoring and air testing, cardio-pulmonary tests, record-keeping).

What can you do?
Educate yourself. This rule doesn’t only affect the contractor who is creating the hazard. It is very important to understand the regulations when discussing a proposed project with your contractor. This is especially important because most projects occur on the exterior of occupied buildings. Contractors who do not take this seriously are not only putting themselves and their workers at risk, but they also put the customer, the building occupants, and the public at risk. This is also important to consider on a multi-trade
construction project where there are other workers in close proximity. Ask your contractor to provide you with a copy of their Crystalline Silica Exposure Control Program and review how they will specifically address your project.