Water is a precious comodity as Charles Fishman (fellow Palmetto Panther) notes in his latest book, The Big Thirst.
In regard to construction though, water is an adversary to be respected and redirected. The first defense is crafting the site with a French drain around the building and channeling the water away as much as possible. Although it sounds foreign, we have Henry French from Massachusetts to thank for making French drains "main stream"...
Wikipedia outlines French drains below:
A French drain,[1] blind drain,[1] rubble drain,[1] rock drain,[1] drain tile, perimeter drain, land drain or French ditch is a trench covered with gravel or rock that redirects surface and groundwater away from an area. A French drain can have perforated hollow pipes along the bottom (see images) to quickly vent water that seeps down through the upper gravel or rock. French drains are common drainage systems, primarily used to prevent ground and surface water from penetrating or damaging building foundations. Alternatively, the French drain technique may be used to distribute water, such as a septic drain field at the outlet of a typical septic tank sewage treatment system. French drains are also used behind retaining walls to relieve ground water pressure. The earliest forms of French drains were simple ditches, pitched from a high area to a lower one and filled with gravel. These were described and popularised by Henry French (1813-1885) a lawyer and Assistant US Treasury Secretary from Concord, Massachusetts[2] in his book Farm drainage.[3]
French drains are often installed around a home foundation in two different ways:
Buried around the foundation wall on the external side of the foundation
Installed underneath the basement floor on the inside perimeter of the basement
In most homes, an external French drain or drain tile is installed around the foundation walls before the foundation soil is backfilled. It's laid on the bottom of the excavated area, and a layer of stone is laid on top. In many cases, a filter fabric is then laid on top of the stone to keep fine sediments and particles from entering. Once the drain is installed, the area is backfilled and the system is left alone unless it clogs.
Installed underneath the basement floor on the inside perimeter of the basement
In most homes, an external French drain or drain tile is installed around the foundation walls before the foundation soil is backfilled. It's laid on the bottom of the excavated area, and a layer of stone is laid on top. In many cases, a filter fabric is then laid on top of the stone to keep fine sediments and particles from entering. Once the drain is installed, the area is backfilled and the system is left alone unless it clogs.
While an external French drain can operate for ten years or more without the need for maintenance, it's prone to clogging without any warning and can eventually lead to a flooded basement. When there is no filter fiber, sediments can make their way through the stone as years pass and clog the drain, and when the filter fabric is present, that can instead clog with sediments. It may be wise to provide cleanouts, much as is done with sanitary sewers, to provide access for inspection with a camera snake. Also, a French drain that is not installed with a sump pump counts on gravity alone to drain foundation water, and if the house is not located on a hill or near a steep incline, finding this slope can be problematic. Additionally, maintenance on an external French drain involves expensive exterior excavation, which includes removal of walkways, shrubberies, porches, gardens, and anything else along the perimeter. Installing a French drain around the inside perimeter is most commonly done after the house has been built. Most commonly, this is done in response to a wet basement or right before performing a basement finishing. To install this kind of drain, the perimeter of the basement floor is jackhammered down to the footing and the cement is removed. A layer of stone is laid down, and the a perforated drain pipe is laid on top of it. Water is collected from the basement wall floor joint as it enters, and a sump pump is installed to pump the water out of the house and away from the foundation.
The system is easy to maintain once installed, and the sump pump will need annual maintenance to perform properly. An interior French drain is much less likely to clog than an exterior, partially due to the fact that it is not sitting underneath several feet of soil.
Interior French drain installation is an effective way to waterproof a basement but requires the use of a sump pump.
We actually like to install a back-up emergency sump pump with an alarm, just to be sure.
In this Monumental Renovation, we are building both internal and external French drains and two sump pumps.
Working in and around the excavating for new plumbing and gas lines and the geothermal well drilling rig, let the French drain digging commence!
and the crane used to take out the steel firescape....
This is actually inside the basement!
