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If you want to know more about tiny house septic system, then read on.
Yes! Living in a tiny house can be super exciting for people who have wholly embraced the tiny lifestyle.
But guess what?
Like every other living arrangement, tiny house living comes with unique drawbacks, including issues like bathroom waste disposal.
Even though most tiny homes out there are fitted with composting toilets or special septic tanks for holding waste, you’ll eventually have to drain them, which can be pretty messy and inconvenient.
For tiny house enthusiasts who live in a permanent structure, we strongly advise setting up a septic system.
Now, the big question is, what is a tiny house septic system?
Well, a tiny house septic system is a brilliantly laid out treatment structure for wastewater installed underground.
This structure leverages technology and nature to treat waste produced in tiny homes.
While septic systems are mostly found in rural areas, having one in your house will improve how to get water to your tiny house for the restroom.
How does a Tiny house drainage work?
Before we bring you up to speed on tiny house sewage options available for you, we would like to take a minute to bring you up to speed on how drainage works for tiny homes.
But before we go into the nitty-gritty of plumbing and drainage for tiny homes, It’s important we highlight some of the unique differences between black water and greywater.
Greywater is pretty much clean water coming from the washing machine, the shower, and the sink in your tiny house.
Even though greywater may contain hair, soap, bacteria, dirt, grease, and more, greywater is reusable, especially when disposed into the ground.
Plants can benefit greatly from the residues in greywater as they can lock in the nutrients hidden in these residues.
On the flip side, blackwater is toilet waste composed of urine and feces.
Except adequately disposed of, black water will heavily pollute the dumping area, which we are sure you’re not ready to deal with.
If you live in a modern home, you’ll need to put a lot of effort into managing black water.
What we simply mean is here is taking steps like digging trenches.
Once that’s done, you can go ahead and install all the relevant pipes for your drainage and plumbing.
However, for tiny houses, you have to explore a different strategy.
Since small homes are designed to be portable, fitting expensive pipes everywhere you travel to wouldn’t be a practical solution.
Many tiny homes on wheels we have come across take almost the same routes as recreational vehicles like RVs: They store their water waste in separate compartments until they can empty them at a dumping station.
Also, we have seen other tiny houses on wheels think outside the box by installing a composting toilet or an incinerator toilet in their home.
These types of toilets turn blackwater into soil or ash.
With these options, you can manage the weight limit of your home.
However, if you live on-grid and plan to travel with your tiny house now and again, you’ll not be disappointed to opt for a septic system.
With an adequate septic system, the ground will absorb water waste while storing solid waste in its chambers until it entirely breaks down and decomposes.
How A Tiny house Septic System Works
Now that you know a thing or two about tiny house drainage, it’s time we take you through how tiny house septic system works.
We are sure you‘ll love every bit of information we have here.
While urban areas provide sewer points, you’ll most likely find septic systems in remote areas.
A typical septic system has two distinct parts: the septic tank itself and the drain field, or what many experts call soil absorption field.
With a tiny house septic system, you’ll need to set up drainage pipes around your home, especially along areas leading outside or underneath your tiny mobile home.
These waste pipes are installed in such a way that they converge and connect to a septic tank, which is designed to separate floatable materials like grease, solids, or oil in the wastewater.
Floatable materials usually remain in the septic tank while bacteria break down bodily waste.
Also, the system allows liquid to be discharged accordingly.
The liquid, called effluent is removed via pipes nicely buried in the drain field.
Sometimes, materials like sawdust and peat are brilliantly laid out around the soil absorption field to neutralize odor and any pollutants in the waste.
Setting up your tiny house septic system
Before you kick off the installation of your tiny house septic system, it is always a smart move to check with local authorities to secure the necessary building permit.
And because regulations can vary from one region to the next, it’s always wise to consult a contractor.
This way, you’ll get all the details, along with the specifics.
That said, the general regulation requires that a household septic tank have at least a 1000-gallon capacity.
But since you live in a tiny home that will probably accommodate just yourself or your significant other, you can decide to go for a septic tank that can at least hold between 750-900 gallons.
Once you have secured your permit, the next thing you’ll need to do is choose the materials for your septic.
In terms of materials, plastic, steel, fiberglass, and concrete are some of the popular options we have come across.
Here is how these materials level up against each other.
- Concrete: This tiny house septic system material will cost you between $600-$1000. Surprisingly, it has a lifespan of almost 40 years. While it is a tad heavy and will take up more space, which honestly you don’t have enough of, it is also more expensive to install than other options we will explore shortly.
- Plastic: If you opt for plastic materials for a small septic system for one toilet, you’ll end up spending between $900 to $1000 to have everything nicely set up and ready to use. But with a lifespan of over 40 years, we are sure this wouldn’t be too expensive. That said, we like that this option is lightweight and more affordable to install when you compare it with the concrete option we highlighted earlier.
Also, you won’t have to worry about roots and soil causing a crack to the plastic due to its ribbed design.
- Fiberglass: When you consider the upfront cost of this material, you may think it is an expensive option, especially since it will cost between $1400 to $1,600. But guess what? In terms of installation, it is still pretty much more affordable than concrete. Besides being lightweight, another exciting thing about this material is that it will prevent roots from pressing into the tank. And yes, this material also has a 40 years lifespan.
- Steel: Compared to all three options above, steel isn’t such a great option for building tiny house septic tanks. And that’s because the material is prone to rust. In terms of cost, you’ll spend between $800 to $1000 if you decide to tow this direction. Also, in terms of lifespan, steel can only deliver 20 years.
Tiny house septic system cost
Are you brooding about tiny house septic system cost and looking for all the specifics?
Let’s give you the cost breakdown of tiny house septic hookup.
Depending on where you plan to build or park your tiny house, the labor required for installing a tiny house septic system will cost you anywhere from $1500 to an excess of $5000.
And if your tank is too heavy to move around or you have a lot of ground space that needs to be cleared, you may end up paying even more.
While this may look like an unreasonable price to pay, keep in mind that with this option, your septic tank will only have to be pumped out every 4-5 years.
Compared to an inexpensive option like a holding tank system, which requires pumping out every couple of weeks, a septic tank system is always the better alternative.
Besides opting to install a tiny house septic system, you may also want to consider adding a vent pipe to the mix, especially if you want to prevent odor from taking over your home.
Thankfully, this shouldn’t be a big deal, especially with the help of an experienced septic tank specialist who knows the perfect place to put a vent pipe in your home while also ensuring that your toilet flushes correctly.
Also, getting a professional to handle this task will ensure that the pipes are run directly into the tank and far away from your home.
When setting up your tiny house septic system, keep in mind that the tank should be as far away from your house as possible.
And that’s because a septic system that is installed too close to your property can end up softening the ground and sinking your home.
Also, it’s vital to protect your septic tank from groundwater, heavy rains, and any nearby plants’ roots.
Doing this will help maintain its functionality.
Things to consider before installing a a septic tank
Before you proceed to build a reliable septic tank system for your tiny house, here are some things you want to consider:
Tank material: A tiny house sits on a smaller lot and has limited space for tank installations.
So instead of going for a bulkier tank, an intelligent thing to do is choose a lightweight septic tank that is easier to transport and install.
If you don’t want to stress yourself too much, you can opt for a fiberglass septic tank.
We like this option because it is durable and will remain fully active for many years.
Also, the material can prevent roots from breaking into the tank.
And yes, it is easy to transport and install on a small lot.
Another exciting option is a plastic tank.
Besides being easy to transport and install, a plastic septic tank is also pretty affordable than other options out there.
Tank size and capacity: If you plan to live in your tiny home more permanently, then you’ll need to install a tiny septic tank.
And yes, we always encourage going for a 750 to 900-gallon capacity tank.
With this type of tank installed in your home, you have more than enough space to flush and dispose of waste properly.
Also, regulations on the type of septic tank you can install in your home vary from region to region, so make sure you consult with local authorities to get a second opinion.
Tank Location: Location is a big deal when installing a septic tank in your tiny house.
A lot of tiny homes may be fitted on wheels or a trailer.
And just so you know, this trailer’s support dramatically depends on the ground below it.
To this end, if your septic tank is located too close to your house, the ground can become too soft, forcing your home to cave in.
That’s why experts always recommend installing your septic tank away from your home.
Don’t forget that heavy rains and groundwater can also impact your septic tank.
That’s why it’s always a good idea to keep septic tanks entirely away from your home.
Frequently asked questions
Are septic tanks for tiny homes expensive?
Well, it depends on the type of material you want.
If you opt for a septic tank made out of fiberglass, you’ll end up spending between $1400 to $1600 on materials alone.
This is not to mention the cost of labor.
On the flip side, if you want something a little bit more affordable, you’ll not be disappointed to opt for a plastic septic tank, which costs between $900 to $1000.
Can I build my tiny house septic tank?
Sure, building a tiny house septic tank can be pretty tricky, but guess what?
You can do it yourself.
All you need to do is get all the relevant materials, watch a couple of videos on YouTube, and you’re ready to roll.
Is there a specific septic tank size for a tiny house?
Since you have limited space to play with, experts always recommend going for a small-sized septic tank for your tiny house.
Any septic tank with at least 750-900 gallon capacity should do.
