| Mild Steel Mesh | Manufactured to BS 4483 usually employed in sizes D49 or A98 to reinforce de-bonded and floating scr... | |
| Mitred Valley | The intersection of opposing roof slopes where the tiles or slates are mitred together forming a clo... | |
| Modillions: | A series of moulded bricks that project and form brackets below a cornice.... | |
| Moisture Expansion | The increase in dimension of materials, such as ceramic, due to changes in prevailing moisture condi... | |
| Mortar Bucket | Used for mixing mortar and transporting onto roof.... | |
| Nails | in various lengths and gauges according to requirement in either, Copper, Aluminium, Bronze or stain... | |
| Natural Bracketing: | Sometimes it becomes necessary to form, or cut, a temporary access opening through a wall. The top o... | |
| Niche: | A circular recess formed in a wall to house a statue or other ornamentation. They are usually sphero... | |
| Noggings | Short timber struts fixed between joists to strengthen or stiffen a timber base before tiling.... | |
| Non Vitreous | Ceramic tiles having water absorption in excess of 7%... | |
| Notched Trowel | Used for the application of adhesives to walls and floors. Notches are of various sizes, square or r... | |
| Offset Footings: | See Footings.... | |
| Open Slating | Slates which do not abut against the next slate in the same course but have an open space between th... | |
| Open Time | Length of time an adhesive applied to a substrate retains its ability to bond effectively to a tile,... | |
| Open Valley | Normally formed in lead or similar metal laid on boards, purpose made valley tiles or trough valley ... | |
| Oversail Verge | Where outside rafters extend beyond brickwork incorporating a Barge Board.... | |
| Pamments | A thin paviour of brick texture used for internal flooring in areas subject to hard wear. May be 225... | |
| Parging: | Application of a coat of lime mortar used to form a smooth internal lining to a brick flue; care nee... | |
| PEI Rating | A means of classifying a glazed tile's ability to withstand varying levels of foot traffic, running ... | |
| Pencil | Thick leaded flat sided pencil for marking points on roof... | |
