Painting damaged brick

[lumpyhammock]

I need to seal the damaged brick in the interior walls of my garage. The brick is shedding dust and mortar "crumbs" all over the garage floor and surfaces. If I touch or brush the walls they just keep "shedding" - not the right word, but I hope you get the idea. Anyway, is there something I can spray on the walls that will stop this falling stuff problem? Thanks.

[pushkins]

What you are seeing is called "spalling".
Before you attempt a repair there are some things you may need to address first. Most often spalling is caused by water/moisture , make sure there is no water from a leaky gutter or downspout running down this wall. I also see shingle related moisture penetration that causes much the same problem as your seeing now.
Sometimes spalling occurs as a sign of age and cheap materials used in the making of the bricks. Low quality clay and low temperature firing results in more porus bricks, high density clay with long and high temp. firing results in very dense bricks. If the property is anywhere in the 80 - 100 year age bracket the technology for firing bricks wasn't as good and often resulted in more porus bricks.

The simplest way is to spray on a sealer. You can use polyurethane either water based or oil, there are products available at most big box hardware stores that will do the job as well, many will be marketed towards driveway/paver sealing and will do the job just as well for your purposes.

Make sure you clean as best you can the surface without scraping out the mortar, a large old paint brush is a good tool for this job, gently brush away as much of the dust as possible, then spray on the poly. You can also brush on the poly as well but you need to make sure you keep a wet brush and it is much more time consuming than spraying.

DO NOT seal the bricks if there is a moisture problem, make sure you address this area first.