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East Wayne Street Historic District <br />Prohibited <br />Wood siding shall not be resurfaced with new material which is <br />inappropriate or was unavailable when the building was constructed, <br />such as artificial stone, brick veneer, asbestos or asphalt shingles. <br />Sandblasting or the use of harsh detergents shall not be used on <br />masonry including brick, stucco, limestone, flagstone, and <br />sandstone. This method of cleaning erodes the surface material and <br />accelerates deterioration. Brick surfaces shall not be painted unless <br />they had been painted originally. Repointing shall not be done with <br />a mortar of high Portland cement content which can often create a <br />bond That is stronger than the building material. This can cause <br />deterioration as a result of the differing coefficient of expansion and <br />the differing porosity of the material and the mortar which can result <br />in serious damage to adjacent brick. Paint shall not be removed from <br />masonry surfaces indiscriminately. <br />Joints <br />Hot <br />l8ricks, expand) <br />Cold <br />(Bricks contract) <br />Normal <br />ed <br />too fun <br />A. flexible Mortar <br />(Lund <br />e, ,.. •..-..,� !!! <br />Mortar compresses <br />Mortar flexes <br />Wide feather: <br />B. Inflexible Mortar <br />(Cement) <br />edge susceptible �• -. —• ,.• <br />to spelling <br />. ". <br />{ .. <br />' �A <br />.. •` <br />joints <br />Slightly <br />recessed <br />Figure 6. Comparison of visual effect of fol! matter joints vs slightly <br />rectssrd joints. Filling joints too full hides flet actual joint thickness <br />and changes the character of the original brickwork. <br />Guidebook <br />Incorrect <br />Mortar not Cleaned out to a <br />sufficient uniform depth - <br />Edges of brick damaged by toaf <br />or grinder. Creates wider joint. <br />Correct <br />Mortar Cleaned out to a uni- <br />form depth—about I- deep. <br />Undamaged edges of brick. <br />Figure 4. Con,varis" of incorrect and correct Freparanon of mortar <br />joints for "cunning. onnaing: Robert C, Mack and Dmnd W. look. <br />Not Recommended <br />Waterproof or water repellent coatings or surface <br />consolidation treatments should not be used on masonry <br />surfaces unless required to solve a specific problem that has <br />been studied and identified. Coatings are frequently <br />unnecessary, expensive, and can accelerate deterioration of <br />the masonry. Mortar joints which do not need repointing <br />should not be repointed. <br />Hot <br />l8ricks, expand) <br />Cold <br />(Bricks contract) <br />Normal <br />A. flexible Mortar <br />(Lund <br />e, ,.. •..-..,� !!! <br />Mortar compresses <br />Mortar flexes <br />f <br />B. Inflexible Mortar <br />(Cement) <br />Spallfng Ciat:ks open up <br />Figwe �. Diagratnmvne sketches showing effects of w,,veran a change uvon masonry. Flenbh, mortar (A) expands and contracts with ternerrneurt <br />changn. Bricks bonded by n"Oesible mortar (B) tend to spall at the rages (the area of greatest strrsst in hot weather and separate from flit mortar <br />when it is cold. This latter condition ovens cracks. permnnng the entry of water and cawing additional deterioration. Adavred from Maintenance <br />of Old Buildings, Docummt DI0. National Swedish Institute for Building Research, Stockholm, 1975. <br />page 42 <br />