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Mobile ViewBASEMENT CEILING VAPOR BARRIER BASEMENT HEAT LOSS BASEMENT WATERPROOFING BRICK WALL DRAINAGE WEEP HOLES BUCKLED FOUNDATIONS due to INSULATION? BUILDING NOISE DIAGNOSIS & CURE CRAWL SPACES CRAWL SPACE DRYOUT PROCEDURES CRAWL SPACE GROUND COVERS CRAWL SPACE INSULATION RETROFIT CRAWL SPACE SAFETY ADVICE CRAWL SPACE VAPOR BARRIER CRAWLSPACE MOLD ADVICE MOLD CLEANUP by MEDIA BLASTING MOLD ON DIRT FLOORS SUMP PUMPS CONDENSATION or SWEATING PIPES, TANKS CONDENSATION on WINDOWS & SKYLIGHTS DEW POINT CALCULATION for WALLS DEW POINT TABLE - CONDENSATION POINT GUIDE EFFLORESCENCE, Salts & White / Brown Deposits ENERGY SAVINGS in BUILDINGS ENVIRONMENTAL HAZARDS - INSPECT, TEST, REMEDY EXTERIORS of BUILDING FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP FIRST PRIORITIES BUILDING ENTRY PROCEDURE AFTER FLOODING CRAWL SPACE SAFETY ADVICE DRINKING WATER - EMERGENCY PURIFICATION DRINKING WATER - EMERGENCY SOURCES ELECTRICAL SAFETY for Flood Damage Inspectors FLOOD RESPONSE CHECKLIST FLOOD DAMAGE RFERENCES FLOOD VENTS & FLOOD PORTS FLOOD-CAUSED MOLD, PREVENTION FLOODED HEATING EQUIPMENT REPAIR FLOODED WATER HEATER REPAIR FLOODED SEPTIC SYSTEMS, REPAIR FOUNDATION CRACKS & DAMAGE GUIDE FOUNDATION DAMAGED, by FLOODING FRAMING DAMAGE, INSPECTION, REPAIR MOBILE HOMES, DOUBLEWIDES, TRAILERS Mold in Fiberglass Insulation Mold on Books, Book Conservation Mold on Fiberboard Insulating Sheathing MOLD PREVENTION AFTER FLOODING MOLD PRODUCTS, INEFFECTIVE MOLD RESISTANT CONSTRUCTION SEPTIC SYSTEMS & FLOODS SEPTIC BACKUP PREVENTION SEWAGE BACKUP, WHAT TO DO SEWAGE BACKUP TEST & CLEANUP SEWAGE BACKUP PREVENTION SEWAGE CONTAMINATION in BUILDINGS SEWAGE NITROGEN CONTAMINANTS SEWAGE PATHOGENS in SEPTIC SLUDGE SEWAGE PUMPS SEWER BACKUP PREVENTION SEWER GAS ODORS SEWAGE & SEPTIC CONTAMINANTS SEWAGE CONTAMINATION in BUILDINGS SEWAGE PATHOGENS in SEPTIC SLUDGE WHEN TO STOP LOOKING FOR MOLD Wind Damage to Roofs FLOOD DAMAGED FOUNDATIONS FLOOD VENTS & FLOOD PORTS FLOODS IN BUILDINGS-mold FLOOR, CERAMIC TILE FLOOR DAMAGE DIAGNOSIS FLOOR TYPES & DEFECTS FOOTING & FOUNDATION DRAINS FOOTINGS EXPOSED, Repair Methods FOUNDATION BULGE or LEAN MEASUREMENTS FOUNDATION CONSTRUCTION TYPES FOUNDATION CONTRACTORS, ENGINEERS FOUNDATION CRACKS & DAMAGE GUIDE FOUNDATION WATERPROOFING FRENCH DRAINS FREEZE-PROOF A BUILDING FROST HEAVES, FOUNDATION, SLAB HEAT LOSS in buildings HUMIDITY LEVEL TARGET ICE DAM PREVENTION Ice Dams: Comparing Two Houses INSULATION INSPECTION & IMPROVEMENT MOBILE HOME INSPECTIONS MOISTURE CONTROL in BUILDINGS MOLD in FOAM INSULATION, RESISTANCE MOLD INFORMATION CENTER NOISE / SOUND DIAGNOSIS & CURE ODORS & SMELLS DIAGNOSIS & CURE PLUMBING SYSTEM INSPECT DIAGNOSE REPAIR SEPTIC SYSTEM INSPECT DIAGNOSE REPAIR SEPTIC SYSTEM PUMPS Sewage Ejector Pump Grinder Pump What is a Sewage Ejector? Sewage Pump Clog Damage Free-Standing Sewage Grinder Pump Septic Pump Alarm Systems Septic Pump Buyers Guide Septic Pump Duplex System Designs Septic Pump Inspection & Maintenance Septic Pump Installation Guide Septic Pumping Stations SUMP PUMPS SEPTIC PUMPING REPAIR SEPTIC SYSTEM DEFINITIONS SEPTIC SYSTEM DESIGN ALTERNATIVES SEPTIC SYSTEM DESIGN BASICS SEPTIC SYSTEM TYPES, MASTER LIST SEPTIC TANK, HOW TO FIND SEPTIC TANK PUMPING SCHEDULE SEWAGE BACKUP, WHAT TO DO SEWAGE BACKUP TEST & CLEANUP SEWAGE BACKUP PREVENTION SEWAGE PUMPS SEWAGE PUMP CLOG DAMAGE SOUND CONTROL in BUILDINGS STAINS on BUILDINGS - QUICK GUIDE STAIN DIAGNOSIS on BUILDING EXTERIORS STAIN DIAGNOSIS on BUILDING INTERIORS STAIN DIAGNOSIS on ROOFS STAIN DIAGNOSIS on STONE STAINS on INDOOR SURFACES: PHOTO GUIDE STRUCTURAL INSPECTIONS & DEFECTS SUMP PUMPS SEPTIC SYSTEM PUMPS Sump Pump Discharge Sump Pump Inspection Sump Pump Types Submersible Sump Pump Guide Pedestal Type Sump Pump Guide Battery Backup Sump Pump Choices Water Powered Sump Pump Guide Sump Pump Single vs Duplex SWEATING (CONDENSATION) on PIPES, TANKS TERMITES, ROT TOILETS, INSPECT, INSTALL, REPAIR TOILET ALTERNATIVES TOILET REPAIR GUIDE TOILET TYPES Toilet Types, Flush Methods TOILETS, DON'T FLUSH LIST TRAPS on PLUMBING FIXTURES VAPOR BARRIERS & CONDENSATION in BUILDINGS VENTILATION in BUILDINGS WATER ENTRY in buildings ATTIC LEAKS Moisture or Mold BARRIERS, EXTERIOR WATER BASEMENT CEILING VAPOR BARRIER BASEMENT De-Watering Systems BASEMENT HEAT LOSS BASEMENT LEAKS, INSPECT FOR BASEMENT WATERPROOFING BASEMENT WATER ENTRY PREVENTION CATCH BASINS Chimney Leaks CONDENSATION or SWEATING PIPES, TANKS CONDENSATION on WINDOWS & SKYLIGHTS CORROSION in ELECTRICAL PANELS CRAWL SPACE DRYOUT PROCEDURES DEW POINT CALCULATION for WALLS DEW POINT TABLE - CONDENSATION POINT GUIDE DRYER VENTING DRYWELLS, FRENCH DRAINS for FLAT SITES DRYWELL DESIGN & USES EFFLORESCENCE, Salts & White / Brown Deposits ELECTRIC PANEL MOISTURE EXTERIOR WATER SOURCE ELIMINATION FLOOD Damage Assessment & Repairs FLOOD DAMAGED FOUNDATIONS FLOOD VENTS & FLOOD PORTS FLOODS IN buildings-priorities FOUNDATION DRAINS, INTERIOR FOUNDATION WATERPROOFING GEOTEXTILES & DRAINAGE MATS GRADING & SITE WORK, EXTERIOR GUTTERS & DOWNSPOUTS HUMIDITY CONTROL & TARGETS INDOORS HOUSEWRAP AIR & VAPOR BARRIERS LOG HOME Leak Diagnosis & Cure LOG HOME Condensation &Moisture MOISTURE in BUILDING WALLS, EFFECTS MOISTURE in CELLULOSE INSULATION MOISTURE CALCULATIONS MOISTURE CONTROL in BUILDINGS MOISTURE METER STUDY MOISTURE PROBLEMS: CAUSE & CURE MOLD in buildings MOLD PREVENTION AFTER FLOODING MOLD RESISTANT CONSTRUCTION PERIMETER DRAIN SYSTEMS ROOF VENTILATION SPECIFICATIONS Soffit Intake Vents & Attic Condensation SEALERS, Basement Floor & Wall Moisture SEWAGE CONTAMINATION SITE & SURFACE DRAINAGE SUMP PUMPS GUIDE SWEATING (CONDENSATION) on PIPES, TANKS VENTILATION in BUILDINGS VENTILATION DESIGN PROBLEMS & SOLUTIONS VENTILATION, WHOLE HOUSE STRATEGIES WATER ENTRY in BUILDINGS WET BASEMENT PREVENTION WINDOW / DOOR AIR LEAK SEALING HOW TO Window Flashing & Sealing Guide WINDOW LEAKS INTO BASEMENT WINTERIZE A BUILDING WATER PUMPS & TANKS & WELLS WATER SUPPLY & DRAIN PIPING More Information |
This article explains how sump pumps are used in buildings, describes the types of sump pumps, and describes how sump pumps should be installed, inspected, and maintained. We explain the difference between a sump pump, simplex and duplex sump pumps, a septic effluent pump, a sewage grinder pump, and an effluent pump. This article explains the various types of pumps and their purchase, installation, inspection, and maintenance. InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers nor with topics or services discussed at this website.© Copyright 2012 InspectAPedia.com, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website. What is a Sump Pump?
Our sump pump photo (left) is not a wonderful installation, but you can see the pump motor (red arrow), pump float switch (orange arrow), and flexible pump discharge pipe (white arrow) clearly. The water inlet in tihs case is at the bottom of the pump assembly (blue arrow). Sump pumps are light-duty and unlike septic or sewage pumps, sump pumps have no ability to pass solid debris other than perhaps fine soil or silt that may be in groundwater. Some manufacturers may also call sump pumps de-watering pumps or submersible sump pumps. If you are confused between SUMP PUMPS used to remove ground water septic pumps (SEPTIC SYSTEM PUMPS) used to move sewage or septic effluent then also see SEPTIC SYSTEM PUMPS. A sump pump is normally installed in a pit at the low end of a basement or crawl space floor or in another location where water needs to be removed such as in a boiler pit or an outdoor well pit. On occasion we find sump pumps installed outside of a building foundation to remove water from around the foundation of a poorly-sited (too low) building which has no natural drainage path to dispose of ground water by gravity.
This condition pertains when water is entering a building through foundation walls, often because the roof drainage or surface runoff are directed right against the building foundation itself. Keeping gutters and leaders working and correcting outside drainage errors are critical in keeping water out of a building. Doesn't it make more sense to prevent water from coming into a building than to let it in and then pump it out? In our flooding basement photo at above left, notice that there is a flood-line about half way up that oil storage tank? The little sump pump shown in the white bucket in the center of our photo is never going to handle such a huge volume of water. And even for modest water entry, the projection of that sump bucket lip above the floor level means water has to rise a few inches in this basement before it can even flow into the sump pit!
Septic pumps, sewage pumps, grinder pumps, and effluent pumps are not sump pumps, and they are discussed beginning at Sewage Ejector Pump Grinder Pump. The distinction among these pump types is important. Choosing the wrong pump can mean a short operating life for the pump, an unreliable system, and unnecessary expense. There may be some confusion, depending on with whom you speak, because people don't always use just the right terms for construction or septic system parts - and the right sewage pump term, or right septic handling product versus the wrong one can be an important distinction. Two Types of Sump Pump Installations - Simplex and Duplex Pumps
Two Types of Duplex Sump Pump Installations: Alternating and Reserve
A simple installation provides a pump control float switch that turns on the backup pump only water in the pumping chamber reaches a level above that normally handled by the primary sump pump. This approach provides both pump backup and the ability to handle surges in building water entry loads on the sump pump system. Alternating septic pump design: the two sump pumps are installed at the same location but are wired so that the pumps take turns, first one, and next cycle the other pump is turned on by the float switch. This pump hookup is more common among septic pumping stations than among home sump pump de-watering systems, but it may be appropriate where a large volume of ground water has to be kept constantly out of a building. An example we've seen was in the basement of a home on Long Island, NY in which the level of the basement slab was so low that flooding from Long Island sound would be nearly constant if the pumps failed. The alternating sump pump approach has the advantage that both pumps are being exercised regularly, which reduces the chance of the ugly discovery that in the event you have to rely on a backup sump pump which has been sitting idle, waiting its chance to run, has in the interim, died. Four Common Types of Sump Pumps
Water & flooding alarm products are available in a variety of forms including battery-powered devices (we show one at Sewage Ejector Pump Grinder Pump) and even devices which can turn a light in a home or make a telephone call or inform an alarm company if a building is being subjected to flooding. Considering the very high cost of flood damage cleanup and mold remediation, we consider flood alarms a great idea for buildings which are often left unattended. Where does the sump pump send its Discharge Water?
Sump pumps that have been added to an older structure often pump their discharge to the ground surface where it runs to a storm drain or area drainage setting. If you have such a system be sure that the sump pump discharge empties where it meets these criteria:
How to Calculate the Water Inflow Rate = Calculate the Necessary Sump Pump CapacityTypically most of us just buy a 1/4 hp or 1/2 hp sump pump and throw it in the pit and see what happens. But you can guesstimate the rate at which water is flowing into the sump pit by knowing the sump pit dimensions and observing how long it takes the pit to fill to a measured depth. At Static Head of Water in the Well we give details of how to calculate the volume of liquid in a cylinder (if your sump pit is round) using pi (3.14) and the radius (1/2 the diameter of the cylinder) squared. Volume cylinder = 3.14 x (water height in inches ) x (cylinder diameter in inches /2)2. Example using an 18" diameter joint compound bucket as a sump pit, and assuming that it takes water 1 minutes to fill the pit to 1 inch.. Volume = 3.14 x (1 inch of water) x ( 18 / 2)2 Volume = 3.14 x 1 x 81 = 254 cubic inches of water rose in the sump pit in one minute Water in-flow rate to the pit = 254 cubic inches per minute Convert cubic inches to gallons as follows.
254 cu.in. / 1728 = .15 cubic feet.of water flowing into the sump pit per minute
.15 cu.ft. x 7.5 = 1.1 gallons of water flows into the pit per minute This example let's us state a simple "rule of thumb" for joint-compund bucket-sized sump pits.
Choosing a De-Watering Sump Pump: Typical Pump Capacities in HP, Lift, & GPM Pumping RateSump pumps for residential use range in horsepower from 1/4 HP to xx. Typical sizes are 1/3 HP and 1/2 HP. Prices (2012) run from about $100. to $200. for submersible pump models. Pedestal pumps and light duty sump pumps may sell for less than $100. Sump pumps are rated for several important factors including horsepower and pumping capacity in gallons or liters per hour - a figure that varies by pump lift height. An individual sump pump's capacity will vary depending on the height to whch it has to lift its discharge water (higher lift means fewer gallons per hour) and other factors such as diameter and number of elbows in the discharge piping. Watch out: be sure to consider both the anticipated de-watering flow rate you'll need and the pump's lift requirements. Typically if you are pumping out of a basement sump pit to ground level that's more than 5 ft. but less than 10 ft. of lift. But installations that have to lift higher distances and/or pump over longer distances and through multiple piping elbows need a more powerful pump.
Guide to Inspecting & Troubleshooting De-Watering Sump PumpsSump pumps on newly constructed buildings are often connected to the building foundation drain. We consider this a bad practice. It is a rare home more than 20 years old whose footing drains are intact. If a footing drain discharge itself becomes clogged or damaged, sending the sump pump discharge into that system will not work: you'll simply flood another section of the building foundation, basement, or crawl space, or you may overload the existing foundation drain causing building water entry. Connecting a sump pump to a municipal sewer drain is bad practice and illegal in some communities. You're adding to the municipal sewer plant's water overload during wet weather and you may thus be contributing to the discharge of raw sewage from the overloaded municipal treatment facility right into the environment. Where permitted, we prefer to route a sump pump to a storm drain, or where soil conditions permit it might be discharged to a drywell. De-Watering Sump pump inspection checklist
These simple sump pump dewatering trouble diagnostics may resolve pump capacity questionsIf the sump pump motor is running or too frequently, constantly check the following:
Frequently Asked Questions (FAQs) about Sump PumpsQuestion: Does using a sump pump cause foundation undermining & increase of water movement towards the building?This was the most informative article I've read during my extensive online research on the topic of "Basement Flooding" (see BASEMENT WATER ENTRY PREVENTION) . Ground water/high water table has been determined the cause of water entry into my basement "pit" area underneath my main sewer trap. We have a Basement Watch Dog Dual Sump Pump with battery backup installed however the constant presence of groundwater in our pit continues to worry us. Our Staten Island, NY home location is situated where the properties behind, to the left and right of us are elevated. PVC fencing with sealed bottom moulding prevents rain water from cascading over the concrete/paver surfaces; however it is our belief that the groundwater underneath from all three directions have found a hydrostatic relief in OUR PIT! What recourse do we have? Any advice you can give us would greatly be appreciated. - Joe Apap 09/2011 Reply: increases in water flow towards sump pump, foundation undermine risk, possible solutionsThanks for the nice note, Joe; we've been working hard on wet basement and wet crawl space information, particularly since recent hurricanes and tropical storms have led to so much flooding. Increased water flow towards sump pump pitIndeed sump pumps as basement de-watering systems work better over time precisely because the ultra fine soil particles pumped away open improved water drainage passages towards the sump pit. One of the first sump pump installations I worked on back in 1969 was installed to reduce the entry of water that used to squirt into a basement through its walls during heavy rains. When the sump pump was first installed it did not immediately stop the water entry, though it reduced it. After just a few years the sump seemed to keep the water table below the basement slab and no more water squirted thorough the basement walls even in wet weather. Of course other conditions could have changed as well. I have not been able to find data, and I doubt there is reliable data, about the "reach" of sump pump water movement past the building where it is installed. Sump pumps might undermine a building foundationI've read a few reports that in areas of fine soils a highly active sump pump may remove enough soil fines to actually cause foundation settlement or tipping. But it may just be urban legend - I've seen reports but no hard data. Use an intercept drain system to reduce water movement towards and under a building, septic drainfield, or similar concerns If it's cost justified you could consider a curtain drain around your property. Such a drain, a ditch to an adequate depth and filled with No4 crushed stone and perforated piping led to an outdoor pumping station could intercept water from neighbors and keep it away from your home. Your outdoor pumping station will need to be deep enough to be frost proof and it will need to discharge to an approved destination such as a local storm drain. Also see BASEMENT De-Watering Systems. Questions & Answers regarding this articleQuestions & answers about how to choose, buy, install, & use sump pumps to keep water out of buildings Ask a Question or Search InspectAPediaHTML Comment Box is loading comments...
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