Drainage
French Drain Installation in Charleston, SC
A trench that gives water somewhere to go, and somewhere to arrive.
A trench that gives water somewhere to go, and somewhere to arrive.
Quick answer: A French drain is a gravel trench with a perforated pipe, and whether it works depends on the outlet: water must discharge somewhere lower that is not already wet. In flat ground with a high water table that sometimes means a sump and pump. The right filter fabric and stone keep fines from clogging it. Southeastern Renovation installs French drains across the Charleston area, including Daniel Island, Summerville and North Charleston, as a licensed SC general contractor (CLG.127339). Call (843) 718-8177.
Related: Is Standing Water in My Crawlspace a Problem? · Grading and downspout fixes.
Water enters along the length of the pipe and leaves at one end. If that end discharges somewhere that is also wet, or uphill of anything, the drain fills and stops working — and a full french drain is a trench holding water against whatever it was meant to protect.
In ground with a high water table, an outlet at grade may not be enough and a sump may be needed to lift the water somewhere it can actually go. That is a design question that should be settled before anything is dug.
Fabric and stone specification decide how long it lasts. Fines migrating into the stone clog a drain from the inside over years, and the fabric is what stops that — the wrong fabric, or none, produces a drain that works beautifully for two seasons.
We take this work across greater Charleston, from Summerville, Goose Creek and North Charleston to Mount Pleasant, Daniel Island, West Ashley and the sea islands. More on our drainage services.
That is the question that decides whether the drain works at all. It has to discharge somewhere lower that is not already wet.
In high water table ground that sometimes means a sump and a pump rather than a gravity outlet, and it should be settled before anyone digs.
Usually fines clogging the stone from the inside over the years, or an outlet that silted up or was buried.
Both are preventable at installation and expensive to fix afterwards.
It can, if the water is arriving from the outside. If the crawl space is damp because humid air is condensing in it, a drain outside changes nothing — those are different problems with different fixes and they are frequently confused.
They can, with a planned outlet. On flat, low ground a trench with nowhere lower to discharge fills and holds water, so the design starts with where the water will go (sometimes a sump and pump) and with downspouts and grading, which are often the cheaper fix.