Brick and Stone Replacement for Spalling and Failed Masonry

Almost always because moisture cannot leave the wall through the joints, so it leaves through the brick instead. Historically mortar acted as a bedding material, not unlike an expansion joint, rather than as a glue, and moisture migrated out through the joints; high lime mortars are more permeable than denser cement mortars. When moisture evaporates from masonry it deposits soluble salts, on the surface as efflorescence or below it as subflorescence, and salt crystallizing inside a unit creates pressure that can spall or delaminate the outer surface. The National Park Service's own photograph of this failure names hard portland cement mortar less permeable than the soft bricks as the cause and describes water pressure eventually popping the surface off the bricks. There are two other routes to the same place. A mortar stronger than the brick will not flex, so the wall relieves its stresses through the units. And anything abrasive that takes the fired skin off exposes the soft core to freeze thaw, which this climate runs hard.

Yes, and it holds if the reason they failed is dealt with at the same time. Cutting out and replacing units is ordinary masonry work. Setting new brick into hard dense joints in a wall that is still wet is not a repair, it is the same experiment with a later start date. So the sequence is: find and close the water route, establish what the existing mortar and brick actually are, choose a mix that is softer and more vapor permeable than the units, then replace. The National Park Service's blunter version is that more damage is done to historic brick buildings by improper pointing than by almost any other treatment, and that hard mortars with high concentrations of portland cement will often make the surrounding masonry deteriorate faster. A quote that lists a brick count and says nothing about the mortar has not answered the question you are really asking.

Rarely to the point of being invisible, and it is better to plan for that than to hope. Old brick is often out of production, and the match has four parts: size, texture, color and how much water the unit absorbs. The last is invisible and matters most, because a replacement much denser than its neighbors becomes the hard part of the wall. Laboratory analysis of the old mortar helps the joint rather than the brick: what it is most useful for is identifying the sand by gradation and color, since sand is the largest ingredient by volume, and that is what lets the color and texture of the mortar be matched with some accuracy. Where the brick itself cannot be matched, the usual answer is to move salvaged original units to the elevations that are seen and put the new brick where they are not.

Both make it more likely, and the federal guidance is unusually direct about it. Preservation Brief 1 states that water repellent coatings are frequently applied to historic masonry for the wrong reason and often without an understanding of what they are meant to do, that they can be very difficult if not impossible to remove if they fail or discolor, and that most importantly their application is usually unnecessary, because water penetration is seldom due to porous masonry: it results from poor or deferred maintenance, and it names leaking roofs, clogged or deteriorated gutters and downspouts, missing mortar, and cracks and open joints around door and window openings. It adds that a coating reduces vapor permeability, so vapor that does get in can condense at a cold spot into liquid water which, unlike vapor, cannot escape through the coating. New York's preservation office warns in the same direction about modern materials over masonry leading to future moisture damage. And painting brick on a pre 1978 house puts every future repair on that wall under the federal lead rule, which is a cost you hand to yourself.

It changes who may lawfully do it and how. EPA's Renovation, Repair and Painting Rule covers anyone paid to disturb painted surfaces in a home built before 1978, and in New York EPA runs the program itself rather than the state operating an authorized one. The minor repair exemption is 20 square feet of exterior painted surface, and when painted components or portions of them are removed the entire surface area removed counts, so cutting brick out of a painted wall passes that quickly. Work in the same 30 days counts as one job, which closes the option of splitting it into small visits. Federal work practice standards then prohibit grinding, sanding, power planing, needle guns, abrasive blasting and sandblasting on painted surfaces during covered work unless the machine has a shroud or containment system and a HEPA vacuum collecting dust at the point of generation, operated so that no visible dust or air release occurs outside the shroud. Given that 85.5 percent of City of Syracuse housing predates 1980, this is the normal case here rather than an edge case. Ask to see the firm's EPA lead safe firm certification, and if dust is drifting across the yard the work is not being done the way the rule requires.

Possibly, and only if you ask before you start. New York's Historic Homeownership Rehabilitation Tax Credit is a state income tax credit equal to 20 percent of qualified rehabilitation expenses on repair, maintenance and upgrades. You have to own and live in the house, it has to be listed in the State and National Registers individually or as a contributing building in a listed district, and it has to sit in a qualifying census tract. Total qualified expenses have to reach 5,000 dollars with at least 5 percent spent on exterior work, which repointing or brick replacement clears easily. The catch is the sequence: all projects must be approved before work begins, and the program also states that replacing repairable historic material is never recommended and that damaged material should be replaced in kind. The National Park Service's records list nineteen districts inside the City of Syracuse, with Strathmore By the Park at 332 contributing buildings, Scottholm Tract at 266 and Onondaga Highlands and Swaneola Heights at 260, so a great many ordinary houses qualify without their owners knowing. Look the address up first, because repointing in June and applying in September loses the credit.