Installation Guide: Home Standby Generator for Emergency Backup Power

Standby generators supply power during any outage you may incur. Generators are permanently connect appliances that operate automatically when the power supply from the utility company is disrupted. The automatic transfer of power happens just seconds after the outage occurs. Many residential generator models operate on natural gas, propane, and diesel.

It’s important to understand successfully adding a standby generator to your home or RV is a large project requiring the skills of several trades. This installation guide will walk your through the necessary steps to take so you have a good experience throughout your standby generator installation project.



Standby Generator Overview


A residential standby generator consists of: a generator, electronic controller, and an automatic transfer switch. This system tracks incoming power from the utility company and whenever the power is lost the system begins a sequence of events taking just seconds to provide power.

When the standby generator is operational, the automatic transfer switch disconnects from the main utility lines and stores power from the generator. In regards to a whole house system, this would include the main service panel. In certain scenarios and configurations, transfer switches may only move specific circuits onto the generator for power. In both cases, the inbound utility lines are confined from any power produced by the standby generator. This critical safety feature stops the standby generator from energizing downstream utility lines which would endanger any line works who may be working on the utility line to restore the local grid.



DIY Project vs Contractor

If you’re a do-it-yourself person please understand most homeowners are most likely not qualified to complete a standby generator system installation by themselves. Installing a generator requires expertise in residential electrical systems. There are also corresponding plumbing skills that are necessary to ensure the pipe runs from a natural gas or propane connector to the generator.

Properly procured building permits and associated inspections are required and a failure to execute these steps during the installation project may void your homeowners insurance.

An option for homeowners is to serve as the general contractor for the standby generator installation project. If you think working as the general contractor for the installation process is a good idea, you’ll need to get this approved from a building inspector.


Choose Your Installation Site

Adhere to the manufacturer’s guidelines for proper standby generator placement. Some generator units may meet fire codes which allow installations to be conducted as close as eighteen inches

from a property, but this doesn’t necessary mean this will meet local codes. If the building inspector objects to the chosen installation site, be prepared to adjust your plan.

For outdoor installations, it’s important to note that standby generators produce carbon monoxide which is an odorless, colorless gas that can reach lethal concentrations in just a few minutes.

Do you have local neighbors? Your standby generator install may affect them with exhaust and noise. You should minimize these factors to the best of your ability.

Procure the height and width specifications of your generator from the manufacturer’s install instructions.

General guidelines are below but these will vary by local building codes and by manufacturer:

  • Top of generator at least 60 inches from the roof.
  • Rear corners at least 60 inches away from doors that open and any windows.
  • Regarding any vents or house openings, the generator can not be closer than 60 inches.
  • The generator must be at least 36 inches from any obstruction.
  • Regarding the rear of the generator, every manufacturer has specific distances to follow.

It’s recommended to install the generator as close to the gas supply to minimize any plumbing costs.

Before Purchase

Contact your local building department and/or homeowners association to get approved of the project. It’s advisable to be issued a building permit before buying any materials for the project.

Decide what things you want powered by the generator when the power goes out. Some essential items could be furnaces, sump pumps, lights, and refrigerators.

Follow a guide to help determine what capacity your generator should be. This step will help you add up the power requirements across all appliances you want the generator to power during an outage.  It’s advisable to add some additional capacity to your standby generator as the power homes require tend to increase overtime.

It may be helpful to contact your local building department about the installation project. Inquire for any suggestions and guidelines. Lots of businesses have information available online. These conversations can help you avoid pitfalls in the future. Pay close attention to any building inspection requirements. Each unique trade may require at least one inspection. You can anticipate inspections on the pad, plumbing, and electrical work. Some American jurisdictions might require finished installation inspections and rough-in inspections.

Interviewing Contractors

After you understand what the building department requires for the standby generator installation, you may start interviewing subcontractors and accepting bids to execute the work.

Make it crystal clear at the beginning a contractor must provide:

  • A certificate of general liability insurance. This mitigates the risk of a contractor damaging your home, causing any injury or death to anyone in the home. The insurance the contractor carries will cover these damages.
  • A copy of the contractors’ local or state license. Not every state requires licenses, so do your due diligence to ensure the selected contractor is licensed.
  • Proof of workers compensation insurance. If your contractor has any employees, they must provide workers compensation insurance just in case the worker is injured. If the contractor does not have this insurance, the employee can sue you for any damages associate with the installation project. Make it clear in writing if the contractor works alone that they cannot bring additional workers to the installation project.
  • Written lien waver. This waver protects you from any lien that might be placed on your home after the services are completed. This waver protects you from a mechanics lien on the home.
  • Guarantee statement. This statement makes it crystal clear what the contractor will fix if there’s any problem after the installation, in addition, how long that guarantee is valid. For example, if something happens 2 months after the install work is completed, will the contractor honor this guarantee or will you be stuck with the bill?
  • Reference checks. Just like proper tenant screening or a new employee hire, conduct references checks to ensure you’re hiring a person with a proven track record.

It’s advisable to procure at least three quotes for each trade. You should also look to see if the contractors have experience installing standby generators. You can also check with the Better Business Bureau for a list of past customer complaints and how the contractor dealt with them.

You shouldn’t select a contractor just based on price. Do your due diligence vetting each contractor by following the above points.

Purchase Decisions

Identify the manufacturer and model generator you wish to purchase. Be sure to select a model that has enough power supply to handle your current and future energy needs. Most generators are sold as a bundle with the automatic transfer switch included.

Be sure to understand how transfer switches work. Understand terminology like sub panel, managed power, service entrance, and whole house power. Verify you have contacts to local maintenance services unless you are capable and willing to execute the maintenance yourself (not recommend unless your a licensed professional).

If your home comes with municipal natural gas, check with your utility company if your gas meter can deliver the required volume and pressure of gas required by the standby generator. If this isn’t the case, you may need to have a new meter installed. Please note properties with LP Gas may require a unique regulator to supply the necessary volume and pressure.

One consideration to keep in mind is fuel consumption. In general, the more power the generator uses, the more fuel the generator will consume. This is important to remember when propane (LP Gas) and/or diesel fuel from an alternative on-site storage tank is leveraged for a fuel source. If you have a large standby generator is may require a larger fuel tank to ensure the generator is operational during prolonged outages that can last days or weeks.


From purchase to delivery, it’s important to procure your building permit and schedule contractors to complete the generator install project adhering to the building permit’s desired time frames.

Don’t forget to make necessary arrangements for extra help or equipment to transport the generator once it arrives at your property. If you have curbside lift-gate services, this means the generator is dropped off at your driveway entrance and needs to be relocated..

If you purchased an air-cooled generator, this will require four movers for a small unit and six+ for a larger generator. If you purchased a liquid-cooled generator power equipment may be required during the installation process.

After Delivery

Relocate the generator in close proximity to the installation site. Already have the pad, plumbing, and electric rough ins completed. If these elements need proper inspection, call your local building department and have an inspector verify the work is done properly. Once these professionals have signed off, you can complete the installation.

Place the generator on the pad and ensure it’s leveled. Now have the plumber and/or electrician complete their work. Once completed and the unit is tested you may call a professional for a final inspection.

Building Inspectors

These professional’s jobs are to ensure the safety of you and others during your generator install project. Often a new standby generator installation requires alterations to your home’s electrical system. Electrical wiring for new circuit breakers, transfer switches, and power modules are complex tasks that a licensed contractor needs to handle. The building inspector will follow up verifying the work was done properly so everyone’s safety is guaranteed.

A standby generator system from Generator Mart will help keep your family and home safe during power outages along with providing convenience and comfort your family has grown accustom to. If you don’t have the time or experience to serve as your own general contractor, hire licensed professionals to complete the installation project. Choose reputable professionals to perform the work to ensure your home and family have reliable power for years to come.