Historic brick needs to be repaired sometimes. Sometimes the mortar gets loose and falls out. Sometimes the face of the brick erodes or falls off, and sometimes bricks just get loose and fall out. In Lancaster, Pa. we see these situations everywhere we go to do work. So many historic brick homes need brick repairs, and there are not many masons out there who are skilled at brick restoration and brick repairs.
We see so many sloppy brick repairs and brick replacements on historic homes that are done with modern brick. These kinds of unskilled repairs stand out to the experienced and inexperienced eye alike--they are unsightly.
Brookline performs historic brick repairs throughout Lancaster, Pa and the surrounding areas. We have done brick repairs in Washington, D.C., Gettysburg, York, Philadelphia, and everywhere in between. One of the most common places for bricks to need repair and replacement is on chimneys. Brookline repoints and rebuilds these chimneys.
We do not use any Portland Cement for historic brick repairs. It does not matter how much Portland a mason mixes into the mortar--it will seal in moisture, become brittle, and start deteriorating the brick within just a few months. It may take a couple years to you start seeing it, but it will show. Even a Type O or Type K mortar, which is a very weak Portland mixture, will trap moisture, deteriorate bricks, and crack.
Lime mortar is what Brookline uses for historic brick repairs. Lime mortar is mortar made from high-calcium lime putty, which is completely different from the Type S (mason's) lime that you find at the builders' supply houses. We never advise using mason's lime for brick repairs.
Use only lime mortar, such as can be found from Lancaster Lime Works in Lancaster, Pa. It may be more expensive, but in the long run it will save tens of thousands of dollars in repairs, brick replacement, and hassle. Lime mortar won't crack and fall out, and it won't cause peeling paint, mildew and mold, and moisture problems on the interior of the building like Portland does.
Mold, peeling paint, and rotten wood on the inside of the historic brick or stone house is usually caused by Portland cement mortar used in the pointing or the stucco on the exterior. The moisture has no way to get out of the wall. It has to go out somewhere! Portland cement will cost much much more than it saves when it comes to brick repairs, brick repointing, and brick replacements.