GLOSSARY OF BASEMENT WATERPROOFING TERMS
GLOSSARY OF BASEMENT WATERPROOFING TERMS
Above-Grade Waterproofing The prevention of a wet basement above ground level through the use of basement waterproofing products or systems that are not exposed to hydrostatic pressure.
Absolute Humidity The amount of water vapor present in a unit volume of air.
Absorption The accumulation of water or vapor drawn directly into the structure’s cells.
Active soils A non load bearing soil mass that is moving due to changing moisture levels.
Acid As the earth around your foundation settles from capillary action, the movement may shift your foundation. Since the air pressure within your basement cannont hold against outside water pressure, the imbalance of pressure may cause your walls to shift and crack. Water absorbs into your wall bringing silt along with it. This silt has an acidic quality which reacts with the adhesive (lime) in the block. This reaction deteriorates the block making it susceptible to hydrostatic pressure which leads to structural damage.
Adobe A brick or building material made of sun-dried earth and straw
Aqueduct A conduit for carrying a large volume of flowing water.
Backfill Material used to fill in an excavation.
Backhoe An excavation machine with a large bucket used for digging and back-filling around the exterior of the foundation in certain types of waterproofing processes.
Basement One or more floors of a structure that are partially or fully below ground level.
Basement Warterproofing the management of water seeping onto basement floors or leaking basement wall.
Bedrock The solid rock layer under the surface of the soil.
Below Grade Any part of the house or structure that is underground or beneath ground level.
Black Mold -MoldExposure- Black Mold - Toxic Mold -People are exposed to mold through the air they breathe, contact with skin, and ingestion. Molds need moisture, a food source, time, and to be left undisturbed. Any source of moisture within an indoor environment can be a possible contributor to a mold problem and poor indoor airquality. It has been stated simply that the best mold removal is moisture control. Mold given the right conditions, wet basement, leaking basement wall, has the potential to cause sickness in susceptible individuals.
Bleeder A Concrete or plastic drain pipe one of the basement waterproofing products, that is installed through the footing or foundation wall to allow transfer of water from the exterior drain tile to the interior drain tile to help prevent a wet basement.
Bowing Walls An inward movement of a basement wall due to excessive lateral pressure on the exterior of a structure which can create a leaking basement wall.
Carbon Fiber Strips Pieces of carbon fiber material another basement waterproofing product that when bonded to a wall will not stretch. These strips, when installed correctly, will stop cracks from growing but must be used before the damage has progressed too farcreating a leaking basement wall.
Capillary Action The wick-like migration of water into the porous walls and floor into a dry basement in the same manner as water is drawn into a sponge.
Caulk A basement waterproofing product can refer either to the caulking substance or to the process of applying it. Caulking as a term has spread to the building trade, meaning the activity of closing up joints and gaps in buildings.
Check Valve A basement waterproofing product device that permits water flow in only one direction and is commonly installed in the sump pumps discharge line.
Cinder Block A pre-fabricated structural component constructed of concrete and cinders that is utilized to construct foundation walls, retaining walls, etc.
Cold Joint A cold joint is the intersection between the end of one concrete pour and the beginning of a new pour. The basic rule is to try to avoid cold joints by pouring straight through until the job is finished. The cold joint is a weak area and could allow the entry of water creating a wet basement.
Clay Soil Soil, which is composed of very fine particles, usually silicates of aluminum and/or iron and magnesium. Clay soil impedes the flow of water, meaning it absorbs water slowly and then retains it for a long time causing a wet basement. Wet clay soil is heavy and sticky, and tends to swell from the added moisture. When dry, clay soil shrinks and settles. The top layer can bake into a hard, concrete-like crust, which cracks.
Cleat Anchor A deadman that is placed in non-active soils to provide lateral support to basement walls.
Condensation The conversion of a molecule of moisture/vapor that when exposed to something colder, decreases in size and squeezes out the denser liquid. This occurs on the cooler walls and floors and pipes in basements much the same as it does on the outside of a glass of ice water, and is always worse when the relative humidity is highest.
Cove/Wall Cove The joint where the wall and the floor meet. This is a common area for water intrusion causing a wet basement.
Cracked Walls or Floors Cracks can form in walls and floors for a number of reasons from settlement, expansion and contraction, water pressure and even by design. The crack is not the problem it is only the symptom. Water entering through the crack is a problem causing a leaking basement wall and only enters when there is enough pressure to force it to penetrate the opening. Eliminate the pressure and eliminate the water to create a dry basement.
Crawl Space A shallow unfinished space beneath the first floor or under the roof usually for access to plumbing, heating ducts and wiring. Crawl spaces should have adequate ventilation to reduce the effects of condensation and to expel stagnant air. Water pipes should be wrapped especially in unheated spaces.
Coating: A coating is a covering that is applied to an object to protect it or change its appearance. They may be applied as liquids, gases or solids. Coatings can be used to fix a leaking basement wall.
Concrete Block Concrete masonry unit used in basement wall construction. Concrete block is commonly used in nominal 8", 10" or 12" widths and is typically 8" tall by 16" long with 2 open cells in the block. The concrete blocks are stacked with alternating vertical joints using mortar between the joints to hold the block together.
Dampness Liquid diffused or condensed in a relatively small quantity on the walls or floor. The effects of moisture created from capillary action or condensation and can often be controlled by heating the space, having adequate ventilation, by using a properly sized dehumidifier or a combination of all the afore mentioned remedies to create a dry basement.
Dampproofing An application or system that is installed when the house is built to resist water vapor or minor amounts of moisture and acts as a backup to primary waterproofing systems. Dampproofing materials are basement waterproofing products subject to the effects of weathering and deterioration and are not effective against water pressure.
Dehumidifier An appliance that condenses air molecules using cold temperatures which in turn “squeezes” the moisture out of the molecule into a tray which must be emptied when full. It is best to have the unit sized for your particular needs by a qualified representative at the local hardware or building supply store as an under-sized unit is of little value.
Discharge Line The pipe used to direct the water away often from a sump pump. Discharge lines should be checked periodically to insure there are no obstructions that might restrict the water flow. Long discharge lines will freeze under the right conditions and should be kept as short as possible in northern climates.
Down Spout The pipe from the roof gutter system that, in conjunction with the leaders, directs the roof water away from the foundation.
Drain Tile Previously made of clay and other hard materials laid end-to-end, drain tile is now commonly made of flexible, perforated polyethylene tubing and is laid near the footing level to aid in the control of a wet basement.
Drain Tile Test A test of the function of the interior drain tile. The drain tile test is performed by: cutting through the floor slab to access the drain tile, flushing water into the drain tile and observing the amount of water entering the sump pump crock. A diminished water flow indicates a plugged or crushed drain tile.
Dry well A hole in the ground filled with gravel or rubble to help cure a wet basement by receiving drainage water and allow it to percolate away.
Efflorescence White mineral deposits showing on face of masonry due to water leaching through the masonry to the dry surface. Usually evidence of a leaking basement wall.
Epoxy Injection The injection of low-viscosity epoxy materials into foundation cracks of the wall. However, if continued movement or settlement occurs the epoxy will crack.
Epoxy One of the basement waterproofing products used to repair cracks in concrete or masonry. Epoxy is a material that can be injected into wall cracks and when cured forms a very strong bond with the base material. Epoxy can be used for the structural repair of a leaking basement wall.
Expansive Soils Soils that swell when exposed to moisture. These swelling soils typically contain clay minerals that attract and absorb water. Another category of expansive soil known as swelling bedrock contains a special type of mineral called claystone.
Exterior Footing Drain A tube or cylinder or box that is normally installed around the exterior perimeter of the foundation footings that collects and directs ground water away from the foundation of the house used in basement waterproofing.
Erosion The wearing away of land or soil by the action of wind, water, or ice.
Gap or Floating Floor – The space left in the cement, usually by the wall, to accept water from above floor level directly into the drainage system which then flows into the sump pump crock, and also to allow for expansion and contraction of the floor.
Grade Reference to the pitch of the exterior ground surface adjacent to the building.
Ground Water Groundwater is water that has drained through surface layers of soil and rock until it reaches a layer of rock material through which it cannot pass, or can pass only very slowly. This results in the accumulation of water in the rock layers above this impermeable layer. The water is stored in gaps in the rock, or between the particles of which the rock is composed often causing a wet basement.
Heaving A situation where a foundation is raised in affected areas higher than its normal elevation due to expanding soils.
Hollow Block Foundation Block walls that have open hollow cavities designed within the block. These cavities allow water to collect inside the walls and cause a leaking basement wall.
Horizontal Cracks Usually associated with bowing or displacement of masonry walls that are not plumb vertically and/or horizontally. Usually the cause of a leaking basement wall.
Hydraulic Cement A basement waterproofing product sometimes referred to as “Hot Patch” because of the heat generated during its exceptionally quick curing time. Often used to patch cracks and small areas that have minor water seepage. May come loose during movement or settlement.
Hydrophilic Chemical properties that draw or absorb water.
Hydrostatic Pressure Still water pressure. Often caused by a high water table it is the pressure exerted against the foundation by various heights of water at rest. The same type of pressure you feel when you try to push a bucket into a pool of water. To some degree, this is the same pressure that allows ships to stay afloat. Hydrolic pressure is a main cause of a wet basement.
Hydrostatic Pressure Rain, melting snow, or springs will contribute to the rising of the water table. This will result in a build-up of pressure underneath the floor and against your foundation walls. This pressure after heavy rains can cause structural damage to your foundation.
Humidity A moderate degree of wetness especially of the atmosphere. High relative humidity can result in wetness condensing on basement walls and floors, causing the growth of mold. The use of a dehumidifier and/or adequate ventilation is recommended to reduce or eliminate the effects of condensation.
Infiltration The inadvertent leakage of water, moisture, vapor or air into the building.
Iron Bacteria An orange colored slimy substance, often mistaken for clay residue, that can clog drainage systems and sump pumps. It is actually a bacterium mold that feeds on the nutrients (iron ocher) of the flowing water. Chemical formulas, such as “Iron Out” will release the bacteria.Another way to release the bacteria is by flushing the system with hot (140 degree) water.
Laser Level Instrument, which emits a beam of light on a certain horizontal or vertical plane. This plane can be used to measure deflection and/or movement of an adjacent plane.
Lateral Pressure The pressures exerted upon a wall by surrounding soils.
Level Instrument used for measuring the plane of a vertical or horizontal surface .Excessive lateral pressure can cause a leaking basement wall.
Membrane A flexible elastomeric material applied to the exterior of the building.
Mildew A type of mold where the pathogen occurs as a growth on the host's surface.
Moisture Vapor Drive: is water/moisture that ‘wicks’ through the concrete and delaminates all other materials. This occurs in concrete floor that are slab-on-grade and floors below grade.
Mold Parasitic, microscopic fungi (like Penicillin) with spores that float in the air like pollen. Mold is a common trigger for allergies and can be found in damp areas, such as a wet basement or bathroom.
Mold Removal: The process by which mold is either physically removed or destroyed by chemical means.
Monolithic Floor When the floor and footing are poured together and become one single unit. The walls are then built on top of the floor. This is usually evident in a block foundation when the first block is a whole block with a mortar line under it on top of the floor.
Mortar Joint A brick being secured to another similar brick or bricks by means of mortar or grout.
Negative Hydrostatic Pressure: is water on the opposite side of the substrate trying to push through, under pressure, which causes all other materials to fail. Floors that are below grade are susceptible to this natural force.
Palmer Valve Storm water discharge valve typically located in the side wall of the floor drain, designed to prevent backflow of sanitary sewer into storm water system.
Pilaster A projection of masonry or a filled cell area of masonry for the purpose of bearing concentrated loads or to stiffen the wall against lateral forces.
Plumb Line Tool for measuring wall deflection consisting of a weight and string. The string is attached at the top of the wall and the weight is at the end of the string located near the floor providing a straight vertical reference line. Measurements are taken from the string to the wall to determine the amount of horizontal deflection in the wall. One of the services of DryMaster Basement Waterproofing specialists, llc. is to measure wall deflection.
Polyurethane A basement waterproofing product that can be injected into wall cracks to prevent a leaking basement wall. Polyurethane should not be used for the structural repair of walls.
Poured Walls Solid concrete walls that are constructed by setting concrete wall forms, installing steel reinforcing bars and pouring concrete into the forms to create a wall.
Poured Concrete Foundations Walls made by pouring concrete into forms, usually held together by tie-rods. When the forms are removed the tie-rods are clipped and this location often leaks because of thermal movement, the curing process and when water pressure is present.
Pressure Relief system Below grade drainage designed and installed by DryMaster Basement Waterproofing Specialists, llc. to reduce the effects of a wet basement due to hydrostatic pressure at a level below the basement floor.
Quick Patch: A Quick Curing, Rigid, Concrete Repair Fluid - Extremely strong 4,700 psi but still remains slightly flexible with 35% elongation. Bonds permanently to concrete, wood, metals, fiberglass, and rigid plastics.
Radon Gas Odorless and colorless slightly radioactive gas that can seep into basements through floor or wall cracks. At certain concentrations Radon Gas is considered a health hazard.
Rust Iron oxide that forms when exposed to oxygen and moisture.
Sealant A material applied to exterior building joints. Sealants should be capable of withstanding continuous joint movement during all weather conditions without failing.
Seepage Water infiltration through masonry walls or floor slab. Seepage is evidenced by damp or leaking basement wall or concrete floor and is an indication that the basement drainage system is overloaded or not functioning correctly.
Silt Substrate particles smaller than sand and larger than clay.
Solid Block Foundation – Block walls that are completely filled with cinder of concrete and have no hollow cavities and usually leak at the mortar joints.
Spall/Spalling The crumbling or breaking off in small pieces of concrete or masonry usually as a result of the freeze-thaw cycle or deterioration (rusting) of reinforcing steel or tie-rods.
Spud Pipe Steel pipe, 3/4" to 1" diameter that is driven into the soil around the perimeter of the building. Water is injected into the soil thru the pipe just above the elevation of the drain tile to test the function of the drain tile.
Stair Step Crack A fracture in a brick or block wall that progresses upward along mortar joints. These cracks can be from either lateral pressures or differential settlement and can cause a leaking basement wall.
Steel Restraints Wall reinforcing used to prevent further movement in basement walls. Steel restraints are typically composed of steel tubes placed vertically against the basement walls at a 32" or 48" spacing.
Step Cracks Cracks in masonry walls that follow the vertical and horizontal joints in the masonry in a stepped fashion. Step cracks can be due to horizontal wall deflection, foundation settlement or shrinkage of concrete masonry.
Stone Backfill Clear crushed aggregate 3/4" to 1" diameter used to backfill excavations. Stone backfill allows for water to migrate easily towards the drain tile located at the basement footing elevation. Additionally, stone backfill will have minimal settlement around the perimeter of the building after backfilling.
Stone Foundation Walls made of large stones stacked on top of one another and usually held together with a mortar type substance. This type of foundation is usually older and when the mortar deteriorates it allows more water to pass between the stones and not only cause a wet basement but structural damage as well. Because the stones are not all the same size and shape, the interior side of the wall is semi-smooth but the exterior side is not, which causes complications when trying basement waterproofing from the outside.
Sump Crock Concrete, steel or plastic basin placed below the floor slab in the lowest area of the building for collecting water from drain tile. Top rim to extend minimum 1" above floor.
Sump Pump Submersible or upright pump located in sump crock to pump water out and away from the building.
Sump Pit – A hole dug to a depth that would accommodate a sump pump and serve as a collection receptacle for water. A sump well liner or crock is usually placed in the pit to keep the walls of the hole from collapsing and should have a bottom on them so dirt doesn’t get pumped out with the water and undermine the foundation.
Tensile Strength – The ability of waterproofing products to resist being pulled or stretched apart to a point of failure.
Thermal Movement Movement, either expansion or contraction, caused by temperature changes.
Tie-Rods A rod (steel) used as a connecting member or brace to hold forms in place when pouring concrete walls that are clipped when removing the forms.
Tuckpoint Term used for the repair of cracks that occur in the joints in masonry walls. Tuckpointing involves the removal and replacement of the mortar between masonry units where cracking along the joints has occurred.
Vertical Cracks – Fractures in basement walls generally caused by differential settlement or heaving soils. Verticle cracks can cause a wet basement.
Wall Drainage Board A basement waterproofing product which is a one piece corrugated or ribbed plastic panel that is placed to form an angle on top of the wall footing and against the masonry wall. The panel extends a minimum of 1" above the floor slab elevation. The wall drainage board is used to drain water from the cores of concrete masonry walls to the interior drain tile.
Wall Deflection The amount of horizontal movement in a basement wall at any given location with respect to its vertical plane.
Wall Irregularities Masonry wall corners or areas in the wall that have thickened sections. Examples of wall irregularities include foundations for masonry fireplaces and wall pilasters.
Wall Slide Horizontal movement of basement wall, usually occurring at the bottom section of the wall.
Water Seepage Water oozed through a porous material or soil. The act or process of seeping; percolation.
Water Penetration/Infiltration The condition where water enters the interior areas of a structure.
Water Table The upper limit of the portion of the ground totally saturated with water. This is a major cause of below grade leakage especially through the floor, cove and lower part of the walls of the basement.
Weep Holes – Holes generally drilled in the lower course of hollow block walls near the footing during basement waterproofing that allow water trapped inside the cavities to escape.