Which Septic Tank?

[Pettrix]

While a 2,000 gallon tank would suffice, I can get a 2,500 gallon tank for only $700 more. Both are precast concrete tanks and both have 2-chambers. I was told it was better to upsize just in case of large loads like family visiting or a party. It also helps out with allowing longer waste processing times due to the increase capacity.

Nobody sells fiberglass tanks out here.

What say you?

 

[Storm56]

I have been getting along quite nicely for 30 years on a 1000 gallon tank, think a 2500 is overkill unless you have a really large family or big parties!

 

[ustmd]

Or are full of it? :laughing:

 

[oldnslo]

What is the code in your area? Around here they are very strict on the minimum size tank that is required. I believe it is based on the number of bed rooms and bathrooms and not the number of people living in the home.

 

[MotorSeven]

How many bedrooms/bathrooms?

 

[creekbend]

We have a 1000 gallon concrete tank. Our Home is three bedrooms, 2 baths, with washer, dishwasher. It was installed 12 years ago. It has been pumped twice. The last time was around 4 months ago and cost $170.00. The owner of the septic service checked the entire system at that time, and informed me that all systems were working properly and in perfect condition.

 

[jinman]

When you get up to the 2,500 gallon range, that sounds like a small RV park. I'd expect going to 2,500 gallons would not be significant unless you also increase the size of your leach field to handle the excess runoff. If I had a huge house, outbuildings, shop, and maybe a business all on the same system, the extra capacity might be needed, but I don't think the increased 500 gallon tank size is worth the extra $700 with everything else remaining the same.

 

[Storm56]

You are correct that the tank must be sized. If memory serves me correct, I think a 1000 gallon tank would service at least a 3 bedroom home, possibly 4.

 

[greasemonkeyok]

Knowing what state you are in might produce more informative answers as the laws in various states are not uniform. Depending on the state, may not even be uniform from county to county.

 

[gcmedica21]

While a 2,000 gallon tank would suffice, I can get a 2,500 gallon tank for only $700 more. Both are precast concrete tanks and both have 2-chambers. I was told it was better to upsize just in case of large loads like family visiting or a party. It also helps out with allowing longer waste processing times due to the increase capacity.

Nobody sells fiberglass tanks out here.

What say you?

As everyone else has stated about the size of the house it is also important to point out how many PEOPLE will be using the system everyday. I have a 1500 gallon tank for 3 bedroom, dishwasher and washer with 2 people on mine. Have had it in for 5 years and it is doing great. (fingers crossed) Has not been pumped only checked out and cleaned filter out regularly. It all boils down to what you put in it and if a legitimate person put it in. Good luck

James

 

[s219]

I don't see much point increasing the tank size beyond what is correct. Ultimately, the tank will fill up after a few days of use and the flow rate going out to the drain field is going to be equal to the flow rate coming in. The drain field is the real determining factor for capacity. So a larger tank won't really help you accommodate extra loads.

A bigger tank will hold more solids and might not need to be pumped out as often. That's about the only benefit I see.

 

[Mousefield]

I would put in the size required by code for your number of bedrooms. This is how they calculate it here, not the number of bathrooms. Remember the bigger the tank the more it will cost to pump out. Bigger is not always better.

 

[Fi-Q]

Here, municipal code is 700 gallons for 3 edrooms or less, 1000 gallons for more than 4 people. Igot a 1000 gallons pre cast concrre tank 3 years ago.

 

[CurlyDave]

I upsized our septic to 2500 gallons when the house was built about 6 years ago.

I have never regretted that decision, and like having the extra capacity for when people come to visit. When relatives come from out of town, they don't just flush the toilet, there are showers, baths, and extra wash loads.

I expect that if we ever sell, it will be a positive to have an oversize tank.

 

[Pettrix]

Here, municipal code is 700 gallons for 3 edrooms or less, 1000 gallons for more than 4 people. Igot a 1000 gallons pre cast concrre tank 3 years ago.

That is how I am looking at it also.

I am out in Arizona and the code required is a BARE MINIMUM, which is 1,700 gallons. It was explained to me this way: The county gives you a septic size based on the household size and occupants. The size is the BARE MINIMUM. I was given the example of house insulation. The code requires BARE MINIMUM of R-13 in the walls. Going to R-20 or higher will cost a little more but it does have benefits (less energy use and more comfort). He said it is like the electric panel, there is a code minimum for the home but going above that can be beneficial if later on you want to add more electrical items and the upgraded panel will be able to handle it because you upgraded during the build.

A 2,500 gallon tank will be able to handle a lot more waste than a 1,700 or 2,000 gallon. This added capacity gives the waste more time to breakdown before entering the leachfield. The extra 500 gallons of capacity comes in handy when you have family over. The tank & system is less likely to be overloaded with the extra capacity.

 

[Fi-Q]

Here, 98% of the people put a 700 gallons fiberglass. It s a small town and we just get the permit for what is being build. So if you just told them it s going to be 3 bedroom, thats what it is, hey don't ask for more size wize. But we do need a land survey and analysis sealed by an engineer wich gave you the deawing for the type of sweeping field you need for the type of soil. I was the first 1000 gallons concrete installation for my septic guy. It came on a flat bed, he had his 2 backhoe at home, they could barely offload it. It finally took a boom truck tu put the tank in the right position. I am build on a old reclaim gravel pit, so I k ow that the 1000 gallons tank would be plenty. I did some landscaping last uear and we hit the end of the sweeping field. It's draining so good that the end of the pipe was still clean like a new one. Plenty plenty of drainage. But i guess if I would be in your shoe, i would put the extra 700$. I am like this, always want to overkill stuff, it s like a disease !!!

 

[Pettrix]

One septic system installer told me this, off the record:

He said that septic companies want you to install the bare minimum tank and leach field. This makes them more $$ money in the long run. As they know you will most likely have a major problem in 10-15 years that will require big $$$ repairs, like a failing leach field. It costs 10 to 20 times more money to replace a leach field than it does to originally just put in a second leach field during the original install.

I was told it would be around another $1,000 to put in a second leach field that can be controlled and switched over via a D-Box valve. While it would cost $10,000 + to replace a leach field years later if one failed. He said with the 2nd leach field you can simply flip the valve and give the one leach field a "rest" and let it recover and use the 2nd one. Then a year later switch it back to the 1st field. Since I got the acreage to do 2 leach fields, he said go for it.

The septic guy told me that the companies don't want to install a bullet-proof septic system that will function without problems for 20+ years. It sort of likens to the making a car "too reliable", as it doesn't bring in the profit for the dealerships and mechanics. It's the breakdowns that make the huge profits.

It makes sense to me to "overbuild" a system instead of doing the bare minimum. Especially when you consider the costs for them to come back out in a few years and repair it. I would rather "invest" the money during the original install and bullet-proof it.

As they say, do it right the first time and you'll save money in the long run.

 

[Pettrix]

I was the first 1000 gallons concrete installation for my septic guy. It came on a flat bed, he had his 2 backhoe at home, they could barely offload it. It finally took a boom truck tu put the tank in the right position.

A 1,000 gallon precast concrete tank weighs 10,000 LBS

While the 2,000 gallon tank weighs 20,650 LBS
The 2,500 gallon tank weighs 23,360 LBS

Here is what it looks like: http://yavapaiblock.com/images/stories/precast/2500st.0806.pdf

 

[MotorSeven]

The septic guy told me that the companies don't want to install a bullet-proof septic system that will function without problems for 20+ years. It sort of likens to the making a car "too reliable", as it doesn't bring in the profit for the dealerships and mechanics. It's the breakdowns that make the huge profits.

It makes sense to me to "overbuild" a system instead of doing the bare minimum. Especially when you consider the costs for them to come back out in a few years and repair it. I would rather "invest" the money during the original install and bullet-proof it.

As they say, do it right the first time and you'll save money in the long run.

I don't agree with that guy's statement at all. Any properly sized, properly installed septic & leach field on proper soil will last well over 20 and most 30-40 years. The biggest failure to any septic system is owners not having the solids pumped out of the tank once every 5 years. When solids begin to run out down the field line that is what plugs it up. Once the leach is full of solids it stops working and has to be replaced.

If you put in a 2500 gallon tank but have the leach field sized for 2,000 gallon it's a waste of money. Here 220' is required for a 1,000 gal, so my guess is that you need to add at least 100' of leach pipe if you go 2500. So throwing in a just bigger tank will allow you to get away with not having it pumped longer ...that's it.

Around here it costs the same amount of money to put in a new leach field on an old tank...as long as they don't have to dig the old one up. I do have some experience with system failures. I had to hand dig up my leach field in 1989 when I lived in "the city" because the yard was too small to even get a bobcat into. It was a 1,000 gallon tank, the leach field was maybe 100' long and consisted of 12" long x 4" in diameter clay pipe. I had a septic guy come look at it once I had it all up. He said that it was the original line that came with the house, built in 1956. Since there was no seal between the sections of pipe, sand had infiltrated into each joint. The pipes were 90% blocked with solids & sand, so it that had not happened the system would never have failed.

 

[dmccarty]

One septic system installer told me this, off the record:

He said that septic companies want you to install the bare minimum tank and leach field. This makes them more $$ money in the long run. As they know you will most likely have a major problem in 10-15 years that will require big $$$ repairs, like a failing leach field. It costs 10 to 20 times more money to replace a leach field than it does to originally just put in a second leach field during the original install.
...

As they say, do it right the first time and you'll save money in the long run.

I think the guy is full of what is going to be flushed into the tank. He wants to sell you MORE so HE makes MORE money.

In NC the state writes the septic rules. Here the septic system is sized by the number of bedrooms with the assumption that each bedroom has two people. How many people now a days have six-eight people in a house? Danged few. Our house's septic system is designed for eight people even though four live in the house. The system right there is over designed by 100%. Worst case we might have six people for a week. I don't remember what size tank we have but it seems like it is around 1000 gallons per code. The NC regulations assume that the septic system for a four bedroom house will handle 250 gallons of waste per bedroom per day! My educated guess is that our entire HOUSE only uses 200-300 gallons a day and most of that is from washing kids clothes. Once the kids get older I think our water usage will drop towards 200 gallons per day. The design assumption in the NC septic regulations are that we are producing 1,000 gallons of waste water a day which is off by at least 300+%.

I don't see what a larger tank does. There is a filter in our tank to prevent solids from going into the leech field and the larger tank will just hold more solids which should be pumped out anyway. NC has recommendations on when to pump, and for us, four years is about right. The septic tank is pumped out every November during presidential elections which makes it easy to remember to do. :laughing: I do not see what a larger tank buys you on a conventional system. Maybe for a system that has a pump it would make more sense because the larger capacity would allow more time to repair a failure.

A 2,000 gallon tank in our system would double our well over capacity tank as defined by the state capacity assumptions. A 2,000 gallon tank would give us almost SEVEN times the capacity we actually use. As it is, the current 1,000 gallon tank is 3-4 times the actual use.

Hopefully some the TBN Septic guys will show up soon add their two cents.

Later,
Dan