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Bill Jobe
07-29-2018, 7:02 PM
I'm putting in a 20' patio trench drain and I'm looking for ideas for something nice other than the pre-fab drains with a grate in top that you set in concrete. I'm considering making one using concrete , then a concave drain the length of the patio formed by using a section of 8" pvc, then smoothed out with a trowel to blend into the brick surface.
This is for surface water only.

Ed Aumiller
07-29-2018, 10:20 PM
We put in a drain above my son's house.... it was about 8' deep, 2' wide with #57 stone...some kind of cloth that let water thru, but no dirt about 12" from ground level..
This allowed water to flow into it but had dirt & grass on top of it...
If you did not know it was there, you would never know it by looking at it...

Bill Jobe
07-29-2018, 11:10 PM
Hi Ed. Having to bulge my eyes to get my mind about your post, but it's kind of you to share your experience. Thank you.

Doug Garson
07-29-2018, 11:26 PM
How about stick with your original idea but fill the 8" half pipe with river rock?

Bill Jobe
07-30-2018, 12:24 AM
How about stick with your original idea but fill the 8" half pipe with river rock?

Thought about that, but set the stones deep and cover them with resin with a smooth finish. The patio has a full Pinoak canopy. Lots of stuff that would be caught in the rocks.

Doug Garson
07-30-2018, 1:00 AM
Not sure how the water would drain thru the rocks if you set them in resin. It would require a lot of resin. Not sure how the resin would stand up to the UV in that application.

Roger Nair
07-30-2018, 10:52 AM
I would lean towards sloping the patio, something like 1 to 1.5 inches in eight feet. No drains to clog and broom maintenance for the deck and the tree litter.

Perry Hilbert Jr
07-30-2018, 11:14 AM
"slope the patio" Yep.

Bill Berklich
07-30-2018, 11:29 AM
+2 on sloping unless you are really up for a "design feature" You could just turn your "trench" into a water feature/stream.

Bill Dufour
07-30-2018, 12:02 PM
Where do you live, does it freeze there, how deep to permafrost? I assume you want a trench because a drain pipe will freeze solid in winter and take forever to melt enough to flow liquid in the summer when the snow melts. Most people in the lower 48 prefer a buried pipe since they can easily keep it deep enough to prevent freezing.
Bill D

Doug Garson
07-30-2018, 1:38 PM
While I agree with sloping the patio it is not a replacement for a drain. The slope of the patio will direct the water to the bottom of the slope, if you don't have a drain at the bottom of the slope the water will just accumulate there. I had that problem before I installed my French drains with river rocks on top, when I power washed the patio the dirty water had nowhere to go so it just backed up on the patio when it eventually soaked into the ground it left the dirt behind on the patio. Leaves do accumulate in the rocks but a yard blower/vac clears them out with reasonable effort.

Bill Jobe
07-30-2018, 2:06 PM
I think I may have caused confusion as to what I want to create by referring to it as a trench drain when I should have referred to it as a channel drain.
I'm wanting to build something other than the small 3"x4" or so channels that are available. They are designed to be set in cement near the lowest point of a sloped patio to drain rain water away. They sit just slightly below the surface of the bricks and are sloped to one side where they connect to drainage pipe that is buried and sloped away from the area to a lower location in the yard where they either empty out at the surface or to a buried container filled with gravel and has holes to allow the water to slowly leach into the underground.
They used to sell concave tiles to build trench drains on the surface near the edge of a patio/driveway, but I think they are no longer available? Perhaps due to people falling because they are smooth and create a slippery surface. Leaves and such make them worse. Anyone who has spent any time riding motorcycles know that fallen leaves on a wet surface is like riding on solid ice.

Perry Hilbert Jr
07-30-2018, 2:08 PM
As I recall, code requires that the exterior grade start at least 12 inches below the foundation sill and that the exterior grade slope away from the house at the rate of 12 inches in 12 ft. (Going by 20 yr recollection) Water will accumulate at the bottom of the slope unless the yard also slopes away. In some very wet areas, this is handled by a submerged drain that starts some distance below the soil and directs away from the house and patio, perhaps into a seepage pit. (it is similar to a french drain, but surrounded by a soil cloth to keep the ground from filling in around the rocks. In some areas this keeps valuable run off water on the premises and provides an easy path for it to become part of the water table. Wen my house was built, we ran such a drain around the outside of the foundation, just below foundation level and it directs away down a steep hill into a seepage pit that is well below the house's basement level.

Roger Nair
07-30-2018, 2:38 PM
Could https://www.bing.com/images/search?view=detailV2&ccid=GbZVMUVg&id=2379BDC9C5A95B87CC6F2180C1482C0B7629C9CA&thid=OIP.GbZVMUVg93FdReJMCq1uOAHaFR&mediaurl=http%3a%2f%2fwww.schneiderconstructioninc .com%2fdrainage%2fphotos-drainage%2fNDS_Figure7-8_ChannelDrain_800.jpg&exph=570&expw=800&q=areaway+drain+details&simid=608019517316402990&selectedIndex=16&ajaxhist=0something like this be okay?

Bill Jobe
07-30-2018, 3:15 PM
Hi, Perry. Glad you decide to share your thoughts.
I have already purchased drainage pipe to fix a bad situation for my attached garage foundation.
I have plenty of both perferated (sp), some with sock and some with some sort of plastic media wrapped with a sock and non-perferated (sp) as well as some hard drainage, some with and some without holes across perhaps within 35-40 off what is the bottom.
Some is for other areas of the property.

Bill Jobe
07-30-2018, 3:19 PM
Where do you live, does it freeze there, how deep to permafrost? I assume you want a trench because a drain pipe will freeze solid in winter and take forever to melt enough to flow liquid in the summer when the snow melts. Most people in the lower 48 prefer a buried pipe since they can easily keep it deep enough to prevent freezing.
Bill D

Yes, sub-zero at times in winter.
My question is about a surface drain for runoff.

Mike Berrevoets
07-30-2018, 6:19 PM
Why not just use an ACO Drain product? They have lots of options.

The slope is built into the drain and they have different grate options.

Bill Dufour
07-30-2018, 6:26 PM
You could line it with roof tiles upside down.
Bil lD.

John K Jordan
07-30-2018, 6:30 PM
More info would help, including (gasp) diagrams of the patio with annotation to show the problem and proposed solution. Is there a slope uphill from the patio and you want to divert water that comes down the hill? Or will the drain be somewhere on the patio to carry off water that gets there? If so, how does the water get there?

To prevent water from reaching the patio I use either a french drain for a little water or shape the ground to form a wide, shallow "ditch" to carry away more water. A shallow ditch can be planted in grass or made of of brick or concrete (such as the drainage ditches you see near bridges on interstate highways.)

If you want to move water that runs onto the patio I might instead consider rebuilding the patio to raise it and trench around. If the water is only from rain and lays in low spots, I'd rebuild the patio. If unsure of how to ensure a dry patio you might consult with a professional.

JKJ

Bill Jobe
07-30-2018, 8:03 PM
The patio lays between the concrete block foundation of a room addition and the slab I had poured for the Amish garage.
I sloped the patio down toward the new slab and need a drain to carry away rainwater that falls on the patio and the gable metal roof of the 20' Amish garage. Since it sits the length of the patio half of the roof runs down on the patio.
These 2 sources of rainwater are all I need drainage for.

Bill Jobe
07-30-2018, 8:22 PM
This is very much like what I was hoping to find.

Bill Jobe
07-31-2018, 9:41 PM
Ok, scrap my idea.
How about hearing from those who've used the prefab channel drains with a grate on top and designed to afix to a down pipe, a 90, then solid drainage pipe directed to the rear of the lot where the ground slopes gently toward the back. Then either a pop-up or simply a low spot with a strainer to keep out rodents.
I'd also like to hear some alternate ideas.

Mike Berrevoets
08-01-2018, 6:35 AM
Alternate idea: If you are doing a brick patio how about using permeable pavers? If you have somewhat sandy soil the permeable pavers would have no runoff and in some cases can handle othe runoff that is shed towards the paver. You could install a sock drain(s) under the permeable pavers to handle more intense rain events.

But, if your soil is heavy clay then this idea usually doesn’t work without some additional drains.

John K Jordan
08-01-2018, 8:21 AM
Alternate idea: If you are doing a brick patio how about using permeable pavers? ...additional drains.

The architect did that for an open area where I worked. Dug up the ground and installed a drainage system, put down some type of permeable base, then a decorative permeable concrete surface.

Bill Jobe
08-01-2018, 10:19 AM
Permeable is not an option. Yes, I have heavy clay soil, but I'm also redoing a patio with the original bricks used prior to buying the portable garage. Just a slightly different design and slope.
To remedy a poor drainage situation in the past I am sloping the patio towards the shed and adding the channel drain. Then simply directing the rainwater (total area 480sq.ft.) to the rear of the lot that slopes to the rear.

I'd also like some suggestions as to what angle grinder to replace my old one. From what I have gathered a good angle grinder can make a huge difference when cutting bricks in half as well as odd shapes for tight spots.

John K Jordan
08-01-2018, 12:51 PM
I'd also like some suggestions as to what angle grinder to replace my old one. From what I have gathered a good angle grinder can make a huge difference when cutting bricks in half as well as odd shapes for tight spots.

Buy quality. I think I have six, Makita, Bosch, Dewalt corded, Dewalt cordless. The Dewalt grinders were the cheapest but still fairly good. The others are over 20 years old, going strong, the biggest differences between them are the type of trigger and the wheel flanges. Keep rock dust cleaned out of the motor.

JKJ

Bill Jobe
08-01-2018, 1:59 PM
Hi John. I see some of them also have slow startup....a feature I like.

Bill Dufour
08-03-2018, 6:20 PM
Best picture I could find look at the bottom and you will see custom? made glazed blue drain tile. This drains the grotto the builder had made by importing Italian stone masons. The tile is only 6-8" wide and a few inches deep. He owned a Quarry with his brother and a paving company. I do not know if this tile came from Italy or was made local by his Friend who owned a pottery factory.
They couple had no children and donated the mansion and 10 acres of gardens to UC Berkeley. It was used as the Universities Presidents house until they realized how unsafe a cast concrete house within 100 feet of the hayward fault is, source of the spring. The gardens are open to the public. His brothers house was given to become Nunnery so no visitors are allowed there.
The university rents a similar house 20 miles from campus and pays about 10,000 a month. Many complain about the cost and how disconnected it is from any campus.
Bill D.

http://www.marvingardens.com/posts/visit-this-secret-garden-in-kensington-but-only-on-weekdays