Masonry Cleaning

New & Restoration Masonry Cleaning

Of all the changes a building can undergo, cleaning the exterior masonry is one of the most visually dramatic. Whether the building is brand new, old, or historic, it is critical that any cleaning done is carried out correctly using the most suitable method for the substrate.

Exterior Building Services (EBS) has been cleaning masonry since its inception in 1979. Our cleaners are highly experienced in all forms of masonry cleaning and we are the first choice for most of Minnesota’s largest commercial masonry and historic restoration companies for all types of masonry cleaning applications.

EBS has been cleaning masonry for nearly 40 years and has extensive experience with all forms of masonry cleaning. We have provided masonry cleaning services on thousands of buildings in the Upper Midwest, including the Minnesota State Capitol, U of M Ambulatory Care Center, Abbott Northwestern Hospital, Walker Art Center, Regions Hospital, Weisman Art Museum, among many others.

Restoration Masonry Cleaning

Restoring old or historic buildings to their original beauty through restoration cleaning is one of our specialties at EBS. Whether the goal is to improve the appearance by removing dirt, soiling materials, or non-historic paint from the masonry; retard deterioration by removing damaging materials; or provide a clean surface to accurately assess the condition of the masonry, EBS has the expertise you need.

When restoring historically significant structures, it is critical to choose a contractor that has experience in this area. Irreversible damage can be caused to historic structures by the use of inappropriate techniques by unskilled workers. This has been the unfortunate fate of too many historically significant buildings throughout the country.

At EBS, we draw on our extensive experience and expertise to make every historical restoration project a success. We take care to assess the entire project and work cooperatively with architects, architectural conservators, and restoration contractors to choose the gentlest and most effective method for cleaning and restoring in order to avoid damage and make your building look its best.

New Masonry Cleaning

Masonry is one of the most durable and beautiful facades found in building construction. The final appearance of finished masonry depends as much on its proper cleaning, as on the excellence of workmanship or the quality of materials used. Proper cleaning of brick or stone work eliminates the unsightly appearance caused by mortar smears, job dirt, and/or efflorescence, while bringing out the natural beauty and color of the masonry.

Improper cleaning practices can cause a host of problems that, in severe cases, can cause the masonry (or adjacent materials) to be ruined beyond repair. It is, therefore, extremely important that the cleaning contractor chosen, be well seasoned and very knowledgeable about all types of masonry and applications.



Water cleaning methods are generally the gentlest means possible, and they can be used safely to remove dirt from all types of historic masonry. 

There are essentially four kinds of water-based methods: soaking, pressure water washing, water washing supplemented with non-ionic detergent, and steam, or hot-pressurized water cleaning. Once water cleaning has been completed, it is often necessary to follow up with a water rinse to wash off the loosened soiling material from the masonry.

Mild Chemical

Chemical cleaners, generally in the form of proprietary products, are another material frequently used to clean historic masonry. They can remove dirt, as well as paint and other coatings, metallic and plant stains, and graffiti. 

Chemical cleaners used to remove dirt and soiling include acids, alkalies and organic compounds. Acidic cleaners, of course, should not be used on masonry that is acid sensitive. Paint removers are alkaline, based on organic solvents or other chemicals.


Essentially granite or marble cleaning, poulticing is used in restoration projects to bring back the original brilliance of a stone. 

Applications range from desalination , sodium hydroxide, or other gels and are used to draw out unwanted salts and soiling contaminants. Poultices are effective at removing paint from stone and especially useful for detailed facades including statues and cornices.