A septic permit is just one of the many new things a log home builder must contend with during the construction process. This can seem intimidating to a first-time cabin builder, but it’s a straight-forward process that we’ll cover here so you can be confident moving forward building your cabin.
While it’s possible to construct your own DIY septic system if you’re building off the grid or living in an unpermitted area, most people will be dealing with building inspectors and county codes that require obtaining a permit when acting as their own general contractor.
Septic permits are a good idea for a number of reasons. You may be confident in your ability to safely construct a septic system, but how confident are you that your neighbor can do the same? By utilizing a permitting process the county ensures that everyone is on the same page as to what is required and the building inspectors can sign off on how the work was carried out. Permits must be obtained prior to installing utilities on your property.
The septic process is as follows: all waste is flushed into the holding tank, which overflows into a distribution box. This box directs the flow into the leach field, also known as a drain field or absorption field.
What does a septic system consist of? The basic components consist of three main parts:
The septic tank (usually 1000-gallon, but determined by the number of bedrooms) and associated lines, distribution box, and the leach (drain, absorption) field. With proper installation, and maintenance a concrete holding tank will last at least 40 years. The average costs of a medium to a large tank can range anywhere from $800 to $1500. To fit a new tank for your home, the average cost is between $1,500 to $2,300.
This system is designed to retain solids and after a holding period of 2 days, the liquid flows out via an effluent filter into the drain field.
Apply for permit - go to your local building department or check with the county health authority. Depending on where you live, you’ll find the local authority in charge of controlling septic systems. Ask for the form, fill it out and pay the fee. These applications generally ask for a diagram of the system and you can get your installer to draw that for you. Usually a rough sketch is enough, with distances noted to lot lines and natural features. This is another benefit of working with professionals that are known by the inspectors.
Perc Test - the county or local building inspectors will come to your property and conduct a percolation, or perc, test to determine the determine the soil composition, system size and location where you wish to put your system. The inspector needs to determine how quickly and how efficiently your drain field will leach and clean itself.
Normally you need to dig a couple of holes about 8-feet deep for the inspector to test the soil. the inspector will check for water within the soil, distance to any standing water such as a creek, distance from property lines, distance from slopes, distance from your cabin (or your future cabin), etc.
The inspector will also lay out a replacement or repair field so that you can replace the leach field in the future if necessary without having to dig up and replace the entire septic system.
Permit issued - If everything is approved according to the application, then your permit is issued. Typically you have one year to install your septic system or you have to pay for a permit renewal. If you haven’t installed your septic system after 5 years, you need to reapply for the permit.
Final Inspection - After your septic system is installed, the inspector will come back out to do a final inspection while the system is still exposed. This ensures that everything is installed to code and set up properly. Even slight elevation changes can lead to premature failure of your system, making this final inspection critical. Once approved, the inspector signs off and you can complete backfilling the trenches.
Building on a steep slope or hill can present additional difficulties with a septic system. This may involve utilizing a submersible sewage pump installed in the bottom of the septic tank, just as you would need if building in a low spot.
Be sure and include an easy inspection and clean-out port.
Some people recommend using enzyme additives to maintain a healthy level of natural bacteria to break down paper, protein, oils and grease and help prevent septic backups. If your septic system ever gets sluggish or doesn't seem to be clearing normally, you can add a leach and drain field opener - I prefer the biodegradable version.
Obtaining a septic permit is not a difficult process but may be unfamiliar to most people who don’t work in the construction business. The permit ensures compliance with local building codes and regulations and safeguards the local waterways and water table from poorly constructed septic systems and drains.