Home Improvement Bleg: Septic Tank edition
So, having fully conceded to living in a pre-industrialized part of the country, we arranged to have our septic tank pumped. Because apparently the wonders of modern plumbing haven’t yet extended 50 miles north of Manhattan and our fecal matter simply gathers in an underground tub. Huzzah.
Anyway, upon digging out the access point, the guy found that instead of a proper cap and/or riser, the prior homeowner put in a makeshift one made out of a plastic cooler which was on the verge of collapsing. This would be horrible news. He recommended a $250 adapter plate plus a $250 riser to bring it up to grade. Oh. And that doesn’t include labor. I’ve done some internet sleuthing that indicate both these price points are way too high. However, our septic opening is larger than standard, meaning I need a specialized adapter (which I think I’ve found but I need to call the company during regular business hours to confirm).
But I’m wondering if all this is necessary. A riser is simply a matter of convenience. It is basically an extended tube that allows access to the tank without digging. But further research tells me that I can probably pour a concrete slab — complete with handles — and then place (but not affix) this over the opening and bury it. This would effectively cap and seal the tank and, while it would require digging every time it had to be fixed, it would turn a $700+ job into a $50 job. The slab would be heavy — likely a two-person job to life — but this would make the seal that much stronger and given that the tank only needs to be cleaned every 2-5 years, seems like a small price to pay.
So… what am I missing? Any reason I shouldn’t take the approach I’ve outlined? Will the septic function any differently with my proposed lid as compared to what the pro recommends? And if my plan is all full of septic fodder, does anyone know where I can find an adapter plate/ring that will cover a 36″ septic opening?
if you’re ok with pouring your own cap, there’s no reason your plan should work that i’m aware of. caveat: i’ve only been dealing with septic for about 11 months, so i possibly don’t know jack. i’ve been looking for a concrete cover/dome for ours as it is just about at grade and the loam is sandy as hhhhhhell out here. no dice yet, but i wasn’t looking that hard.Report
“shouldn’t work” yeeesh.Report
My research has told me almost everyone has gone away from concrete covers and towards plastic ones. Some companies sell forms and handles which you can use to make your own cover assuming it is a standard size.
My thinking is that if their makeshift approach worked, my far-more-thought-out makeshift approach should work. But those are probably some pretty famous last words…Report
The only thing I can add, which is not on point, was that I had to dig up my family’s septic tank when it needed pumping. Our tank was sold old there was no tube. Just a metal cover across the entire tank, say 8 feet across. I had to dig down 4 feet to access this cap. Fortunately, I wasn’t there when they popped it.
That was some nasty work….Report
The risers are there for your benefit… septic tanks can be finnicky; and, if you need to work on them or unclog them you may need better access. I personally would not bury the access, I’ve had far too many issues. The other reason there are risers is so that you can change your filter in the pre-settle tank… do you have one of those (I’m guessing no, since it is an older system)?Report
The phrase “up to code” always makes me nervous. Has your research looked at current code (as interpreted by the authorities there) and whether you’ll need inspections? My state is pretty lenient about letting homeowners in residence do work that’s subject to code, but some aren’t.Report
Indeed. I had some plumbing work done (repiped my house. Replaced nearly 40 year old copper with Pex) and the plumbers went into detail about the city code and how it applied — including the fact that the work had to be signed off by a city inspector when it was done.
I always get a little nervous when a contractor doesn’t bring up the code standards — sometimes it’s because there aren’t any (or he or she considers it a ‘no brainer’ to adhere to them), but sometimes it’s because they’re not planning to deal with them.Report
Does anything make anyone more instantly libertarian than the phrase “up to code” when they are attempting to do their own home repairs?
This is a good point. I’ve put in a call to the necessary agency and will hopefully have an answer (or be directed to the actual necessary agency) soon.Report
Not me. I like having my house remain standing.
Then again, I got to see what “not up to code” looked like. This is an absolutely true story. A co-worker of mine had some electrical work done, which included adding an outlet and moving another one. This by a licensed electrician.
Fast forward about five years, and their house floods from a hurricane. In repairing the house, that particular set of walls had to be opened up — exposing the electrician’s work.
This is how he moved an outlet. He took the outlet to be moved and pulled the whole thing into the wall. He then plugged in an extension cord (the bright orange buy at Walmart sort) and plugged into that socket. He then ran it around the wall and spliced the other end into the new outlet, which he placed on the wall.
Why did he do this? No idea. (Whatever he did with the brand new outlet, instead of the moved one, was similarly bad but I don’t know what the specifics were). The guys doing the work were shocked at it.
Another story — this one I didn’t hear about firsthand — involved a load-bearing wall, some interior rearrangement, and a collapsed ceiling. The work was not ‘up to code’, needless to say. I understand the contractors got sued, and I believe the city got involved as well against them.Report
morat20,
nothing’s worse than aluminum wiring. watching the entire wall go up in sparks…Report
Yeah, aluminum wiring was one of those “it seemed like a good idea at the time” things. Polybutylene pipe goes into the same category. Had to replace the main water line from the meter pit to the shut-off valve at my daughter’s house last fall after it cracked and started leaking a thousand gallons a day. Her house is in a development with probably a couple hundred others, all with polybutylene that will have to be replaced over the next few years (a house up the street from her had the same job done a couple of weeks later). The Fort Collins plumbers and excavators are doing their happy dance. The company that manufactured the pipe and was behind the big push to get it into the national codes was class-actioned into bankruptcy years ago. Sometimes “up to code” doesn’t save you…Report
Michael,
i just find it funny that my 1930’s wiring is better than the 1960-1970’s wiring…
In the 30’s, they were paranoid about electricity causing fires…Report
My other house (the one I rent out), when I bought it, came with 150Amp main breaker. When I looked at the panel, as we were buying the house, I thought the mains wires coming from the outside of the house into the main breaker seems a bit small. I pointed this out to the Home inspector, who grabbed a calibers & measured.
Sure enough, the wires were too small (he’d just replaced the breaker without replacing the old 60 Amp wires). Previous owners had no idea, but they knew the work had been done by a licensed electrician. Turns out the guy was known for doing a job half-assed & then telling the city it was good. Cost him his license, but by then he’d done enough work off book that other electricians were still finding such examples time & again.Report
The guys doing the work were shocked at it.
Metaphorically, or did the damned thing short out?Report
Sounds like my parents septic. The original tank was 60 some odd years old when we bought the house in the late 80’s. The whole top of the tank failed years ago, dad covered it with a giant wooden cover. A replacement tank would have cost $20K+ because a mound system would have to be installed.
Last time I checked, there was still a massive wooden cap over it.Report
I know you probably know this, but use steel reinforcement if you go with concrete.
Concrete doesn’t have much tensile strength and if the handles are at the edges it will likely crack in the tensile axis. The reinforcement is typically in the lower 1/3 thickness of the pour.
Depending on the environment you may want to paint it…Report
Thanks, @citizen . Would a steel plate work? How thing would it need to be? The opening is about 30″x12″ (360 square inches), though it does have a beam that divides it in half, so it is really two openings each about 15″x12″. There would be about 24″ of top soil on top of it. How thick would steel (or another metal) need to be to support that weight? Would it need to be treated in any way to properly protect it from elements?Report
I dunno about plates, but generally folks use a grid of steel cables. It’s to reinforce the concrete, not to supplant it. (This is what bridges and walls look like).Report
not cables. rods.Report
Rebar is typically used for the reinforcement:
http://www.homedepot.com/p/Weyerhaeuser-1-2-in-x-10-ft-Rebar-05366/202094293
https://www.youtube.com/watch?v=mZm_LDiM7-8
Soil only weighs about 120#/cu.ft. The opening you are describing would have approx. 2.5 cubic feet of soil over it. So thats only about 300 pounds. Add a big person standing there and it would be 600.
The real problem with septic tanks is when something drives over them, like cars, trash trucks or tractors. It’s wise to fence them in high traffic areas.
Treatment would be if the soil was high/low ph, OR some rough chemistry in the tank, they can produce corrosive gas if not designed correctly. (Not to mention full strength crystal Drano.)Report
@citizen
I was thinking of using the steel plate/sheet in place of concrete. I’ve found a company that sells plates of varying thickness but they simply give a single number for how many PSI it can support that doesn’t seem to account for thickness. Maybe I’m dumb, but I can’t imagine a 1/8″ sheet supporting the same weight per square inch as a 1/4″ or 1/2″.
I also just spoke with someone who sells the specialty adapter straight to consumers and he said it is prohibitively expensive. He actually said for about half the cost he could create a concrete form that included an opening for a riser. This A) confirmed my basic approach and B) taught me I could do the same thing, basically setting the initial riser pipe in the concrete. I’d need to seriously reinforce the remaining concrete because it’d have a huge whole in the middle, but this would allow me to do it myself and include a riser for all the reasons risers are useful. The riser parts I need are under $100 on Amazon, meaning I can still get the job down for less than 1/4 of the original quote.Report
Can you backfill over the plate with vermiculite/perlite? If there is no traffic, most of the load comes from the weight of the soil, thats probably why the cooler was used, to both displace the weight of the soil, and to cover the hole.Report
I might worry about corrosion in the long-term with a steel plate (stainless probably gets expensive). You’d need to rig something to hold it in place so that it wouldn’t shift. And dude, have you ever tried to bend quarter-inch steel plate? As I recall, you need a hydraulic press rated to 20 tons to put a permanent bend in a 12″ piece of quarter-inch plate.Report
Good point re: shifting of the plate, @michael-cain . I could probably bolt it into place though. But what about something like this: http://www.homedepot.com/p/Master-Flow-24-in-x-36-in-Galvanized-Steel-Flat-Sheet-GFS24X361P/202191776 Is that thick enough to support the weight of the soil?
@citizen
I don’t know what any of that stuff is. I assume it is a synthetic fill that is lighter than soil?Report
That link is showing .012 inches thick in the specifications. Way to flimsy. Generic sheet steel doesn’t hold its shape or load well until it is at least .051 thick. Your much better off with the (.125)1/8 inch.Report
Just chatting over a virtual beer, 30-gauge seems awfully flimsy for this to me. Maybe something like this if one of the standard sizes works? It’s been a long time but I recall that cutting even eighth-inch plate is a pain unless you’ve got the right tools. You might be able to find a local welding shop that would cut one down for you if necessary (or even have a “scrap” piece of plate that would do the job that you could buy cheap).
Extending @citizen ‘s comment, a knock-together wooden frame, some Quikrete, some rebar, and a couple of handles set into the concrete is probably cheaper, as quick, and you could get everything at Home Depot.Report
@citizen ‘s original comment, not the most recent one.Report
@michael-cain and @citizen
Your help here is invaluable. Thank you so much.
Michael, what you describe in your last comment there is exactly what I had in mind. One question about setting the rebar: do I just pour the concrete, press the rebar to the appropriate depth (I doubt I need to be super-precise here), smooth over the top, and assume it will more-or-less set in place?
Also, I’m thinking a depth of about 3-4″ will provide the requisite strength without making it impossible to move into place. Thoughts?Report
I’ve never used rebar for something this small, but I assume the principles are the same: layout a form, place the rebar, and pour the concrete over it. If you try to sink it in, you risk it being uneven and not giving you the structural integrity you need.Report
@chris
“I’ve never used rebar for something this small…”
So many jokes… all of them more offensive than the last.Report
For something like this lid, I think the technique is to fill the forms about half way, then lay the rebar pattern, then finish filling. The old-school concrete guy who lived next door to my mom would probably insist that you lay out the rebar to the side and use wire to tie things together where the bars cross so that nothing gets loose. Like this.Report
It is important for the rebar to be in the lower 33% of the thickness.
3/16″ is about the thinnest I would go with plate (assuming no traffic). 1/8″ was borderline to failing in the stresses at the center in deflection for 300 pounds(no factor of safety). What was the psi the vendor mentioned?
Michaels wisdom is showing in it would be critical to keep the plate centered with several inches of overlap.Report
Thank you, @michael-cain . That is more or less how I envisioned it.
@citizen The plate idea is out. Just too risky. And by the time I get to the thickness that would mitigate the risk, the price is a wash. I’ll do what the one contractor said he would have done for me for $250 but do it myself for $180.
Reinforced concrete with several inches of overlap, a cement adhesive to affix it to the existing lid, with a riser cast into the concrete and capped just below grade.
You guys are the best. Next time you pass through Orange County, New York, drinks are on me!Report
“So, having fully conceded to living in a pre-industrialized part of the country, we arranged to have our septic tank pumped.”
Fun fact: over a million and a half people in the US still don’t have indoor plumbing
http://www.theweathernetwork.com/news/articles/indoor-plumbing-not-as-common-as-you-may-think-in-the-us/26170/?ddlMonth=september&ddlYear=year
Now, it’s (almost always) strictly a sign of rural poverty, but I had a few Greatest Generation relatives in rural Nova Scotia that simply never bothered getting it installed in what were otherwise fairly nice houses. They had lived that way their whole lives, so it just wasn’t a big deal to go to the outhouse. (they all did have electricity though, which is much harder to do without)Report
We lived for three months in a paper bag in a septic tank. We used to have to get up at six in the morning, clean the paper bag, eat a crust of stale bread, go to work down at the mill, fourteen hours a day, week-in, week-out, for sixpence a week; and when we got home, our Dad would thrash us to sleep with his belt.Report
I just found a picture of Glyph as a child, with his siblings.Report
Ah, a picture of me dear ol’ Da. How I hated him.Report