I am installing 2 drain pipes (perforated for ground water & solid from the downspouts) around the perimeter of my house, what size pipe should I use? 3″ or 4″? and what type of pipe? Home Depot sells the cheapy stuff (white on the outside black on the inside) but my local plumbing supplier sells SDR35 which is a lot more sturdy but also more expensive. Is a primer needed as well as glue, what type of glue should be used with each of the materials?
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Are you doing this at the footing level, as in installing a foundation perimeter drain? If so, I'd think the last thing you'd want to do would be to connect your downspouts to it. The downspout drains should run in solid pipe out to daylight, as far from the house as practical. You don't want to add roof water to the ground water already down there. That's one of the main reasons for putting up with all the trouble you get along with having eaves troughs...so you can direct all that roof run-off someplace away from the foundation.
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Yes I am installing separate drain lines '2 pipes', perforated for ground water and solid for rain water. They will in the same trench, the perf will be wrapped w/ fabric and I shall obviously cover it w/ gravel.
Unless there are local code restrictions against its use, you might consider using accordion-pleated flexible pipe. We have pretty good luck with this stuff here. Both perfed & socked and unperfed are available.
Foundation drain size should be 4" unless you've got a major water problem; in that case go to 6". For the downspouts, you can buy an adaptor that goes on the end of the spout with a couple of sheet-metal screws and will accept a 3" or 4" flex pipe.
Dinosaur
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
2 inch is too small! Don't!
It never hurts to use primer. I did on my drains.
There are 3 kinds of "drain pipe".
PVC sch 40 DWV - that is what is used inside.
SDR 35
and Sewer & Drain (ASTM D-2729).
SDR35 and S&D have the same OD and can be used with the same fittings.
Will S&D has the thinest wall it is the only one that is spec'ed for crush resistance. 3000 lbs. But I have never found the definition of that or how it is measured.
Our local HD and Lowes has both the S&D and the SDR35. But often mixed up. And will had fittings for one and the other had fittings for the other. But in practice you can use either fittings.
Unless you are going under an area with some traffic I would just use the S&D. I put in about 250 ft of it about 3 yrears ago.
For the gutters, at least, I would go with 4".
And keep the 2 separate until you hit daylight. Other wise a clog can cause the gutters to dump water into the foundation.
Most people around here instal the cheap pipe if their drainage isn't being inspected. Codes (which do vary) may stipulate what is required. When backfilling one should take care (in any case) especially around the pipes. It's a false economy to use an inferior product when the ramifications of digging up and replacing fractured pipe is enormous.
Sensible to differentiate between roof and surface water - why it's taken so long for the codes to get to that point I don't know!
ciao for niao
To those who know - this may be obvious. To those who don't - I hope I've helped.
Its called Big "O" - 4" Use perforated around perimeter footings, cover with gravel. check with your local lumber supply store.
DO NOTrun your gutter into the foundation drain. Keep it separate.
Run the gutter run-off separately to daylight.
I may be confused, but glue is not used on SDR 35 or on perforated drainage pipe. Your lines should be 4 inch. Run them to daylight, do not twin them together.Piece of cake. Luck.
"I may be confused, but glue is not used on SDR 35 or on perforated drainage pipe"Why not?Now SDR 35 and S&D (both plain and perforated) come in to connection types. Solvent weld and gasketed.Both types have come with bell ends. But the gasketed type have grove that holds an o-ring for the sealing. And they are much more costly.But they are PVC and don't know of any reason not to use the adhesive.