New Home Tips, Trends, and Ideas - Raleigh Custom Home Builders

How to Convert a Three Bedroom Septic to Four Bedroom Septic

Posted by Penny Hull on Tue, Jul 26, 2011 @ 14:07 PM

What to do when your lot is rated for a 3 Bedroom Septic System

"I have a septic rated for a 3 bedroom home.  How do I build a 4 bedroom home on my lot?"
NC build on your lot | expand septic systemThis NC build on your lot builder hears questions like these quite a bit.
Some homebuyers are surprised to find how common septic systems are in North Carolina.
Most lots larger than .5 acres will require a septic system. 
But knowing the right questions to ask, up front, will keep you comfortable.
When buying a lot in the Raleigh area, there are two important septic system questions that need to be answered. 

First - does the lot perk?  If the answer is yes, great! If not, ask your builder to go over the options with you, during our free lot inspection.

Second, how many bedrooms is the lot rated for?  You'll want to make sure the rating supports the number of bedrooms you want to build.

But what if you've already purchased a lot that is rated for a 3 bedroom septic system?

If you're looking to build a four bedroom home but have purchased or are considering a three bedroom septic lot, there are several options.

1.  Septic Options:  Rethink Your Floor Plan

Probably the least expensive option is to rework some of the interior areas of the home.

If you're planning to use that fourth bedroom specifically for an office, a few little changes could allow your custom home plan to be approved by the county.

In general, a room is determined to be a bedroom if it has egress window (a window you could open and leave the room from in case of emergency), a closet, and a door.  Another factor is access to a bath - a bedroom may also have direct access or be close to a bathroom.  

How to Expand 3 Bedroom Perk Septic System | NC Custom HomebuildersBut if your builder converts the bedroom to an office by removing the closet and expanding the doorway to either a wide opening without a door or possibly even a pair of French doors, this could allow you to gain approval to build the floor plan. 

If the fourth bedroom is upstairs, your builder may be able to convert it to an open bonus room or loft.  You'll still have all the same square footage and usable space, but the room will be much more open. 

2.  Septic Options - Panel Block Septic System

If a floor plan change just won't do, you might consider a panel block septic system instead of a standard septic system. 

A panel block system can expand the capabilities of a standard septic system to support at least one extra bedroom. 

But it can also add 25% to 75% to the cost of installing a septic system, depending on how close the original septic system layout came to supporting that fourth bedroom.   

A panel block septic system does need to be approved by the county, and a lot of factors can come into play, such as soil type and requirements that vary by county. 

Every lot is unique.  To best determine your options, have a trusted NC build on your lot builder review your lot and your septic system permit.  They might just have some great ideas for you.

Wake County NC Build On Your Lot Floor Plans

Whether you choose a plan from our gallery of favorite floor plans, or from any architect, Stanton Homes can add special features you won’t find in the house next door.

Browse through some of our favorite available floor plans here. Ask us about thousands of additional options, or even design/build ideas.

One Story Homes

Main Floor Master Homes

Mother in Law Homes

Here’s a look inside our featured custom homes, to give you an idea of how we build.

Ask us how many Signature features come standard. You may be surprised!


Tags: three bedroom septic, septic systems, build on your lot, NC build on your lot builders