page_title: Mortar (masonry)
section_title: Ordinary Portland cement mortar
hierarchical_section_title: Mortar (masonry) / Ordinary Portland cement mortar
caption_attribution_description: English: brick and block laying
context_page_description: Mortar is a workable paste which dries to bind building blocks such as stones, bricks, and concrete masonry units, to fill and seal the irregular gaps between them, and sometimes to add decorative colors or patterns to masonry walls. In its broadest sense, mortar includes pitch, asphalt, and soft mud or clay, as used between mud bricks. The word "mortar" comes from Latin mortarium, meaning crushed.
  Cement mortar becomes hard when it cures, resulting in a rigid aggregate structure; however, the mortar functions as a weaker component than the building blocks and serves as the sacrificial element in the masonry, because mortar is easier and less expensive to repair than the building blocks. Bricklayers typically make mortars using a mixture of sand, a binder, and water. The most common binder since the early 20th century is Portland cement, but the ancient binder lime mortar is still used in some specialty new construction. Lime, lime mortar and gypsum in the form of plaster of Paris are used particularly in the repair and repointing of historic buildings and structures so that the repair materials will be similar in performance and appearance to the original materials.
context_section_description: Ordinary Portland cement mortar, commonly known as OPC mortar or just cement mortar, is created by mixing powdered Ordinary Portland Cement, fine aggregate and water.
  It was invented in 1794 by Joseph Aspdin and patented on 18 December 1824, largely as a result of efforts to develop stronger mortars. It was made popular during the late nineteenth century, and had by 1930 became more popular than lime mortar as construction material. The advantages of Portland cement is that it sets hard and quickly, allowing a faster pace of construction. Furthermore, fewer skilled workers are required in building a structure with Portland cement.
  As a general rule,  however, Portland cement should not be used for the repair or repointing of older buildings built in lime mortar, which require the flexibility, softness and breathability of lime if they are to function correctly.
  In the United States and other countries, five standard types of mortar (available as dry pre-mixed products) are generally used for both new construction and repair. Strengths of mortar change based on the mix ratio for each type of mortar, which are specified under the ASTM standards.
  These premixed mortar products are designated by one of the five letters, M, S, N, O, and K. Type M mortar is the strongest, and Type K the weakest. 
  The mix ratios and are always expressed by volume of .
  These type letters are apparently taken from the alternate letters of the words "MaSoN wOrK".
caption: Laying bricks with Portland cement mortar
exif: {"Image Make": "Canon", "Image Model": "Canon DIGITAL IXUS 50", "Image Orientation": "Horizontal (normal)", "Image XResolution": "180", "Image YResolution": "180", "Image ResolutionUnit": "Pixels/Inch", "Image DateTime": "2010:06:19 13:11:07", "Image YCbCrPositioning": "Centered", "Image ExifOffset": "196", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "180", "Thumbnail YResolution": "180", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "5108", "Thumbnail JPEGInterchangeFormatLength": "5730", "EXIF ExposureTime": "1/320", "EXIF FNumber": "14/5", "EXIF ExifVersion": "0220", "EXIF DateTimeOriginal": "2010:06:19 13:11:07", "EXIF DateTimeDigitized": "2010:06:19 13:11:07", "EXIF ComponentsConfiguration": "YCbCr", "EXIF CompressedBitsPerPixel": "2", "EXIF ShutterSpeedValue": "133/16", "EXIF ApertureValue": "95/32", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "95/32", "EXIF MeteringMode": "Pattern", "EXIF Flash": "Flash did not fire, auto mode", "EXIF FocalLength": "29/5", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "2592", "EXIF ExifImageLength": "1944", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "Interoperability RelatedImageWidth": "2592", "Interoperability RelatedImageLength": "1944", "EXIF InteroperabilityOffset": "2226", "EXIF FocalPlaneXResolution": "11520", "EXIF FocalPlaneYResolution": "81000/7", "EXIF FocalPlaneResolutionUnit": "2", "EXIF SensingMethod": "One-chip color area", "EXIF FileSource": "Digital Camera", "EXIF CustomRendered": "Normal", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF DigitalZoomRatio": "1", "EXIF SceneCaptureType": "Standard"}