Opening of Quotes - North Pumping Station Flood Damage Repairs Proj No. 118-302 - No Quotes Received

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Version 08/25/2021 Page - 9 Public Works Quote F. Preparation Contractor shall protect adjacent windows, utility piping & equipment, masonry and other elements surrounding the work of this section from damage or disfiguration due to repair operations. Where materials are attached to the masonry temporarily remove same to sufficiently allow access to the masonry for required work. Re-attach or re-install at end of project. Provide new attachment hardware where missing, finished to match existing. Contractor shall repair to existing condition any damage to such materials caused by repair efforts or replace with like kind. G. Repointing Remove the damaged or fractured existing mortar joints to a minimum depth of 1", or as much as may be necessary to reach sound material. Take care to avoid damaging existing masonry units or enlarging width of joints. Repair or replace existing masonry units damaged by cutting, spalling and chipping caused by routing operations. Thoroughly remove loose material from joints using low-pressure compressed air. Final preparation of the joint shall be done by hand. Mortar should be mixed carefully to obtain uniformity of visual and physical characteristics and comply with ASTM-C270. Material proportions by volume to produce type N minimum strength. Mortar should be used within 30 minutes of final mixing. Re-tempering is not permitted. After carefully routing and cleaning joints, wet joints thoroughly and then apply fresh re-pointing mortar. Allow water to soak into joints, but joints shall not be visibly wet with standing water during tuck pointing. Fill mortar joints in layers not over 1/4" thick with each layer applied with pressure as soon as previous layer has partially dried. Do not tool each layer smooth; leave surface rough to help bond of subsequent layers. Compress the final packing as much as possible to completely fill joint. Compact joints solidly before final tooling. Tool joints concave to match existing. Take care to not spread mortar over edges of brick onto exposed surfaces. Do not featheredge mortar. Cure mortar by maintaining in a damp condition for 5 days. Allow mortar to fully harden for 10 days after completion of work. Thoroughly clean exposed masonry surfaces of excess mortar and foreign matter using stiff nylon or bristle brushes and cleaning agent. H. General Cleaning Promptly as work proceeds and upon completion, remove excess mortar, smears, efflorescence and droppings. Before cleaning verify that all mortar joints in area to be cleaned have been repointed and are sufficiently hard for cleaning. Test areas to be cleaned to determine the most effective cleaning method starting with the gentlest means possible utilizing brush and water wash at low pressure. If alkaline or acidic cleaning methods are necessary, mask off areas below to protect finishes that may be damaged by chemical cleaners. Start cleaning at the lowest designated wall area and proceed to the top of the wall always keeping surfaces wet below the area being cleaned and rinse frequently to reduce the potential for streaking. After the designated area has been cleaned, wash down the wall areas below. The use of abrasive cleaning, beyond stiff bristled brush, will not be permitted. Clean adjacent and adjoining surface of marks arising out of execution of work of this section. At end of each day’s work, sweep up and remove sand, mortar droppings, dust, dirt, debris, and rubbish. At completion of this work, remove all construction aids and ensure that all sand, mortar droppings, debris, and rubbish have been removed.