Hello All,
We’re planning a new house, French country style. The eves are detailed with crown and dental molding. It doesn’t lend itself well to gutters, so I’m thinking French drains. I plan on good footer drains with gravel backfill. But, I don’t feel comfortable with run off dumping on the gravel and relying on the footer drains. I would an second drain line just below the frost line (3 foot in northern Ohio), but I’m not sure how effective that would be. Any good experience?
Thanks,
Mik
Replies
If you have real concerns you might try to put in dry wells, they are simply holes dug into the ground and then large chunk gravel dumped in .They hold water untill either the ground can absorb it or it dries out.
What you are proposing is so inexpensive, I'd do it.
Both the upper and lower drains should drain to daylight, and be separate from one another, otherwise you'll just dump water from the upper drain to the lower one, more so if an animal crawls up your outlet and dies. (There should be a screen on the outlets.)
You don't need to go below the frost line. If the ground is frozen, you won't be moving water towards the foundation anyway. I'd go a little shallower, say 18", deep enough to be below holes for shrubs.
Of course, you should pay attention to the grading around your home, too. I would recommend sod under the drip line if you want grass there, because it's impossible to get grass started without a gully forming.
You should also not skimp on waterproofing for the basement walls. The old asphalt tar or paints are not too effective. Choose a specially designed modern system. I like the one with sheets of sticky rubber, like the ice and water shield used under roof shingles, but there are other good ones, too.
Enjoy the emotional roller coaster of building a house!
Depending upon the height of the house, and the depth of the overhangs, wind can drive a lot of drip water back at the structure.
If you go gutterless, it is best to make the drip area crushed stone (or similar). This avoids erosion ans muddy splashback.
One way to do this is to use EPDM roofing membrane to form a small 'roof' underground that pitches to drain tile 3-4 ft away from the foundation. Drain tiles goes to daylight or drywell.
Footer drains or none, you do not want to saturate the soil next to your foundation, plus the footer drains will clog sooner with the extra load.
Thie gutter on the ground is common in England and Europe. In the US check out Colonial Williamsburg for what you describe. I used to live in Ohio and after the winter of "78 removed all downspouts and gutters and poured a 2 ft swale around my house with 4 inches of concrete sloped to drain away from the house at all of the corners. Did away with ice dam backups. Was able to direct much of this water to a cistern I built to use to store water for when the yard and garden needed it.
I have now lived in Central Florida for the last 3 years and with no frost or snow to worry with, have done the same thing with geotextile fabric covering the sandy soils and then 6 inches of 3/4 inch round river rock for 2 ft away from foundation. Benefits include no gutter to keep free of leaves, no splash-up onto house and no mower trimming around the house as a little "Roundup"- weed killer keeps it under control.
Thanks to everyone who responded. (Pretty effective way to get some answers on a Sunday). I got some good ideas.
Thanks again,
Mick
You check your local stormwater codes yet?
Gutters leading to bioswales or some other catchment system are required in the Pac NW and probably other places.
Too much runoff from impervious surfaces washes nitrogen and other contaminates into salmon streams and severe runoff literally washes away the eggs.“When we build, let us think that we build forever. Let it not be for present delight nor for present use alone. Let it be such work as our descendants will thank us for; and let us think...that a time is to come when those (heirlooms) will be held sacred because our hands have touched them, and that men will say, as they look upon the labor and wrought substance of them, ‘See! This our father did for us.’ “ --John Ruskin.
Bob,
Good point. I'm on 9 acres of gentle sloping grassed field. I'm sloping topo. leads to more wooded land. I now talked myself into; properly installed footer drain, spray-on rubberized waterproofing on the below grade walls, gravel backfill 3/4 up the wall, a layer of waterproofing membrane forming forming a swale, sloping away from the walls with another drain tile with gravel. A filter membrane on top of the gravel and about 18 inches above soil backfill, topping off with sod and maybe a foot wide strip of gravel??! How that sound?
Mick
Sounds fine to me....but that doesn't mean it's gonna work as intended.
I build them....and also bioswales, catchment trenches and sand filters...here they have to be sized by a civil engineer to meet the hundred-year storm. Without all the inputs as to your climate, soils and codes, we are just guessing...and probably guessing wrong.
We get 60 inches of rain/yr locally with 2"/hr worst-case. The typical stormwater catchment trench designed for a 3-4 BR house and installed by me is 3-5' wide, 3' deep and 120-150' long...filled with 1 and 1/2" drainrock with a perforated 6" ABS pipe in the center and covered with filter fabric. Picture how much water that will hold then ask yourself if your drain will carry that away day in and day out.
Also required here is to catch parking area water....that plus roof water goes into a Type I or Type II concrete box with oil-water Tee before heading for the infiltration trench or filter.
This is serious business out here, code wise. Dunno if it is where you are, but I'd sure do some research beginning with my county building or public works depts, first....
...otherwise you are likely measuring once and cutting twice. Drain construction is simple and really child's play once you teach the child to read the level....the important question is. "How big?"
“When we build, let us think that we build forever. Let it not be for present delight nor for present use alone. Let it be such work as our descendants will thank us for; and let us think...that a time is to come when those (heirlooms) will be held sacred because our hands have touched them, and that men will say, as they look upon the labor and wrought substance of them, ‘See! This our father did for us.’ “ --John Ruskin.
Edited 5/10/2004 8:40 am ET by Bob Smalser
Thanks for the advice. I know the city and EPA are concerned with runoff, and flooding the neighbors. I talked with the city and found that since I'm looking at a 2500 sq.ft. single story, (more roof than on a 2 story, 2500 sq.ft. ) in the middle of 9 acres I don't need to do an impact study. But your point is well taken.
Thanks,
Mick
Appreciate this email thread. I have a tiled concrete deck with living space under it. The water flows off the deck into flower beds next to it. In addition to trying to figure out a drip strip mechanism along the deck's edge, I've been scheming to add a french drain below ground level, but above the footer drains. My objective is to direct the runoff from this large deck area away from the foundation.
Couple questions:
1) What are you thinking of using for the waterproofing membrane?
2) Not sure what you are descibing as drain tile?
3) You find a waterproofing product for your exterior walls?
Almost tempted to 'connect' some sort of membrane to the walls to direct any water that washes straight down walls into the draining system.
Any other insights?
Lokee1,
Some local constractors are using a spray-on rubberized product on below grade foundations. I'm sure of details. The membrane lining would be a pvc base roofing material on which the perf tile would lay on. The tile would be sloped away to eventual day light grade.
Mick
You need to dig 1' wide by 1' deep troughs under all eaves on the house. Box the sides with either PF type pressure-treated 1x6 or cedar (preferable). Keep the top of the 1x6's proud of grade about 2 or 3 inches. Line the bottom of the trough with 100# felt laid in a U and stapled to the inside of the wood a few inches down from the top edge. Pitch the troughs 1"/10' toward a 3x3x3 rockpit at one end. The rock pit should have a 6" 'overflow' drain out of it going to daylight in the event of really monstrous downpours. Northern Ohio is not particularly known for this, but if you're close to the lake, anything can happen....
Fill the trough with ¾ or ½" washed gravel. To do a really neat job, cover the gravel with ½" square wire mesh and tuck it down over the boards, stapled down well. This keeps the gravel from drifting out on to the grass as people walk over it, or getting blown out by the leaf blower. Fill around the trough flush with the top and plant your grass seed. Or fill 2" low, and sod.
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?