Painted Brick Changes How the Joints Can Be Cut

Yes, and the change is practical rather than cosmetic. Under 40 CFR 745.85(a)(3), grinding a painted surface during a regulated renovation is prohibited unless the machine has a shroud or containment system, a HEPA vacuum attachment collecting dust at the point of generation, and no visible dust escaping. Grinding is how mortar joints are normally cut out, so on painted masonry the tool has to change before the job starts.

Already know you need someone out? Call (315) 640-3590, answered 24/7.

The rule that decides which tool may touch the joint

On painted masonry the tool is not simply the mason's preference. Under 40 CFR 745.85(a)(3), machines designed to remove paint or other surface coatings through high speed operation, and the regulation names sanding, grinding, power planing, needle gun, abrasive blasting and sandblasting, are prohibited on painted surfaces during a regulated renovation unless those machines have shrouds or containment systems, are equipped with a HEPA vacuum attachment collecting dust and debris at the point of generation, and are operated so that no visible dust or air release occurs outside the shroud. The same provision prohibits open-flame burning or torching of painted surfaces and permits heat guns only below 1,100 degrees Fahrenheit. Cutting old mortar out of a joint is ordinarily done with an angle grinder. So on a painted wall the question is not whether the mason is careful in general, it is whether the grinder has a shroud and a vacuum on it and whether dust is visibly drifting. That second test is written into the regulation itself, which means you can apply it from your own yard.

Twenty square feet is smaller than any real repointing run

There is an exemption, and it is worth knowing exactly how small it is. Under 40 CFR 745.83, minor repair and maintenance activities, which fall outside the definition of a regulated renovation, are activities that disrupt 20 square feet or less of painted surface for exterior work, and only where none of the prohibited or restricted work practices are used and the work does not involve window replacement or demolition of painted surface areas. Twenty square feet of exterior painted surface is a patch roughly five feet by four. Any real run of repointing, any chimney rebuild and any brick replacement on a painted wall goes straight past it. Two details close the obvious workarounds. When painted components or portions of them are removed, the entire surface area removed counts as painted surface disturbed. And jobs other than emergency renovations performed in the same room within the same 30 days must be treated as the same job for the test, so splitting a painted elevation into four small visits does not produce four exempt visits. On painted older masonry, the regulated case is the normal case rather than the exception.

Cutting mortar is already the dustiest thing a mason does

A second federal rule points the same way, and it singles this work out by name. In OSHA's respirable crystalline silica standard for construction, Table 1 gives handheld grinders used for mortar removal, that is tuckpointing, their own entry, item eleven, separate from handheld grinders for all other uses. For mortar removal the specified controls are a commercially available shroud and dust collection system operated per the manufacturer's instructions, a dust collector providing at least 25 cubic feet per minute of airflow per inch of wheel diameter, a filter of 99 percent or greater efficiency, and a cyclonic pre-separator or filter-cleaning mechanism, plus respiratory protection whether the work is indoors or outdoors. For a handheld grinder used for anything other than mortar removal, the same table requires no respirator at all when the work is done outdoors with equivalent controls. The regulator has put cutting mortar out of a wall in a category of its own. Add paint to it and the shrouded, vacuumed grinder stops being good practice and becomes the only lawful version of the tool.

Do not let anybody blast the paint off

Sooner or later somebody will suggest taking the paint back to bare brick, and abrasive blasting is the quickest way to do it. It is prohibited by name on painted surfaces under the same provision unless shrouded and vacuumed with no visible release, and it is also one of the few treatments the National Park Service describes as starting a decay process that does not stop. Its page on common problems with brick masonry states that a brick wall which has deteriorated to the point of looking unsightly has probably received a treatment that caused the loss of the wearing surface of the brick, and that the treatment was often an abrasive cleaning method such as sandblasting. The blasting takes off the outer, hard surface of the brick and exposes the softer core, water then wicks into those cores, and in a northern climate where winter freezes are prevalent the brick deteriorates through freeze-thaw action. In other words blasting does not merely fail to help. It converts a painted wall into a wall that needs brick replaced. If a proposal includes blasting, that is the moment to stop and get a second opinion.

The paint is part of the water story as well

It helps to understand why a painted brick wall is so often a wall with a moisture history. A coating on masonry reduces its vapor permeability, and Preservation Brief 1 spells out the consequence: vapor that gets into the wall can condense at cold spots into liquid water, and liquid water, unlike vapor, cannot escape back out through the coating. The same brief states that water-repellent coatings on historic masonry are usually unnecessary, that water penetration to the interior of a masonry building is seldom due to porous masonry, and that leaking roofs, clogged or deteriorated gutters and downspouts, missing mortar, or cracks and open joints around door and window openings are almost always the actual cause. It also warns that such coatings can be very difficult if not impossible to remove once they fail or discolor. Read that beside the mortar argument and a pattern appears: every time a less permeable layer is added to a permeable wall, the water is not stopped, it is redirected somewhere worse.

Why the joints have to be cut deep enough to matter

One reason a painted repointing job crosses that 20 square foot line so easily is that the work is not superficial by nature. Preservation Brief 2 specifies removing old mortar to a minimum depth of two to two and a half times the width of the joint, which for most brick joints means removal to a depth of approximately half an inch to one inch, with any loose or disintegrated mortar beyond that minimum depth also removed. The reason is bond: a shallow fill will not hold and will pop out. Every linear foot of joint cut to that depth is painted surface disturbed along both of its edges, and an elevation's worth of joints reaches 20 square feet long before it looks like a big job. It is also why a proposal to skim fresh mortar over the face of old joints, sometimes offered as the cheaper option, is not the same work under a different name.

If your brick has never been painted, none of this touches you

This entire page is conditional on paint. If the masonry on your house is bare brick or bare stone, the federal rules on disturbing painted surfaces do not reach the work, and the questions that decide the outcome are the ones about mortar strength and water instead. If the masonry is painted, whether the rules reach your particular job depends on the age of the building and on how much painted surface the work will disturb, and that is not something a website can settle for your address. It is a fair thing to put to a contractor in writing before anyone starts: does this rule apply to my house, and if it does, how will the joints be cut. Locally the odds are not trivial. The City of Syracuse reports 85.5 percent of its 67,601 housing units built before 1980, Solvay village reports 91.4 percent of its 3,292 units before 1980, the highest pre-1980 share of any place in Onondaga County, and the county as a whole sits at 69.9 percent against 49.7 percent nationally. If your wall is painted and your house is old, ask the question. If you would rather have help getting a straight answer, send us the address and a photograph of the wall.