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Can I put a generator in my garage?

Quick Answers

Putting a generator in your garage can be convenient but also poses some risks. Here are quick answers to key questions:

– Yes, you can put a generator in your garage as long as you take proper safety precautions. Make sure it is well-ventilated and away from flammable materials.

– The fumes from gas-powered generators contain poisonous carbon monoxide. You need to vent the exhaust outside your garage.

– An automatic standby generator connected to your home’s electrical system must be installed by a licensed electrician following all codes.

– Portable generators should only be run intermittently and never indoors. CO fumes can easily accumulate.

– Generator noise may disturb your neighbors if it’s loud. Look for a low decibel model marketed as quiet or install a sound dampening enclosure.

– Check your homeowners insurance policy and local fire code before installing a generator. Some policies require advance notice.

Is It Safe to Put a Generator in the Garage?

Putting a generator in your garage can be safe if you take the right precautions. The main risks are carbon monoxide poisoning, fire hazards, and excessive noise. Here are some key tips for safely installing a generator in your garage:

Proper Ventilation

Gasoline powered generators release dangerous carbon monoxide, a colorless, odorless gas that can quickly cause illness or death with exposure. Proper ventilation is absolutely critical to prevent CO buildup.

There should be plenty of fresh air flow in the garage when running a portable generator. Open the garage door about halfway and open any windows or vents to allow outside air to circulate.

For a permanent standby generator, install venting per manufacturer guidelines to route exhaust outside. This usually involves running the exhaust pipe horizontally or vertically through an exterior garage wall. Consult your generator manual for the venting requirements. Improper venting can allow CO to leak back into the garage.

Avoid Fire Hazards

Fuel and electricity can be a dangerous combination. Follow these fire safety tips:

– Store fuel away from the generator in sealed UL or FM approved containers. Limit storage to 10-15 gallons.

– Do not smoke or operate any open flames near a running generator.

– Keep the generator at least 5 feet from combustible materials like cardboard boxes, rags, or solvents.

– Install a battery-operated CO detector and fire extinguisher in the garage.

– For standby generators, use a transfer switch to avoid backfeeding electricity on utility lines.

Manage Noise Levels

Generator noise can be an annoyance to your family and neighbors, especially at night. Consider these noise reduction techniques:

– Select an inverter or encased generator which are quieter, usually with noise levels around 45-65 decibels.

– Add a sound dampening enclosure which can reduce noise by 10-15 decibels.

– Place the generator on a concrete pad with vibration isolating mounts.

– Point the muffler exhaust away from the house.

– Run during least disruptive times of day.

Proper Installation

Improper generator installation can lead to backfeed accidents and electrical fires. Follow these guidelines:

– Portable generators should only be operated outside in a well-ventilated area. Never run a portable generator inside an attached garage, even with the door open.

– Hire a licensed electrician to install permanent standby generators. They must be properly wired into your home’s electrical system with a transfer switch to prevent backfeeding electricity to utility lines.

– Follow all instructions in your generator manual for grounding, surge protection, and load calculations. Overloading a generator can cause circuit damage.

What Size Generator Do I Need?

Choosing the right size generator involves calculating your running watts and starting watts. Here’s how to estimate the generator wattage you need:

1. Make an Appliance List

Write down all the appliances and devices you want to power during an outage. Your list may include:

Appliance Wattage
Refrigerator 500-2000 watts
Furnace fan 500-750 watts
Sump pump 800-1500 watts

2. Calculate Total Starting Watts

Add up the starting (or surge) wattages which can be 2-3x higher than running watts. This gives your peak power needs.

3. Calculate Total Running Watts

Add together the regular running watt loads under normal operation. This is the continuous power the generator must deliver.

4. Choose Generator Size

Select a generator that meets both your starting and running watt loads. Add up your lists from steps 2 and 3, then pick a generator rated for at least that combined amount.

Allow some extra capacity cushion in case you add more appliances later. In general, a 6500W or 8000W model is sufficient for most homes.

Where Should I Put the Generator in My Garage?

Proper generator placement is crucial for safety, performance, and noise control. Consider these factors when determining the best spot:

Ventilation

Make sure the generator is in a spot where exhaust can be freely vented outside. Avoid corners or alcoves with poor air circulation.

Accessibility

Leave adequate clearance around the unit for refueling, maintenance, and electrical cord reach. 3-4 feet is recommended.

Sound Level

Minimize noise by placing the generator on a concrete pad as far as possible from living and sleeping areas. Point exhaust away from the house.

Convenience

It needs to be reasonably close to fuel storage and transfer switch connections. Consider weather protection like an awning if not storing indoors.

Fire Safety

Keep at least 5 feet away from combustibles. Allow space for a fire extinguisher and CO detector nearby.

A central location along the back or side wall is ideal. This provides good airflow, access, and separation from hazards.

How Do I Vent a Generator in My Garage?

Gasoline generators require careful venting to safely remove toxic exhaust fumes from the garage. Here are some common generator venting methods:

Through-Wall Venting

Most manufacturers recommend a straight horizontal or vertical vent pipe through the exterior garage wall. Follow their guide for proper pipe sizing and terminations.

Through-Ceiling Vent

Running the exhaust pipe vertically through the garage ceiling and roof is an alternative if wall venting is difficult. Requires proper flashing and sealing.

Existing Ventilation Duct

Some use existing vent pipes for appliances like the water heater if large enough diameter. This avoids making new penetrations.

Out a Window

For portable generators only, venting out a window with an exhaust hose is acceptable for temporary use in emergencies only.

Proper installation is a must to prevent leaks or clogs. Avoid 90 degree elbows. All connections should be secured and air-tight.

Can I Store Gasoline in My Garage?

While conveniently located, storing gasoline inside your attached garage is generally not recommended due to serious fire and explosion risks. However, you can safely store limited quantities if you follow strict safety guidelines:

– Store in only UL/FM approved metal containers designed for gasoline. Never plastic or glass.

– Total gasoline should not exceed 10-15 gallons. This is the limit most fire codes allow in residential garages.

– Keep containers away from any sources of heat, spark, or open flames. At minimum 5 feet distance.

– Prevent vapor buildup by using portable containers with self-closing lids.

– Place containers on a non-flammable spill catch pan or concrete pad. Never directly on the garage floor.

– Keep extra containers closed air-tight and store upright to avoid leaks.

– Place portable tanks outside or detached garage when possible. This is much safer than attached garages.

– Consider installing a fire-rated storage cabinet designed for flammables. This adds extra containment.

Storing too much fuel in your garage substantially increases the fire risks. Whenever possible, store only what you need outside in a secure shed or ULV container.

Do I Need a Permit for a Garage Generator?

Most areas require permits and inspections for permanent standby generators but not for portable generators. Here are some common generator permitting rules:

– A permit is required to install hardwired standby generators connected to your home’s electrical system.

– Licensed electricians handle the permit process for installed generators in most cases.

– No permit is needed for a portable gas-powered generator you manually connect to appliances via extension cords.

– There may be permits required for any structural work like new venting through exterior walls.

– Zoning or HOA approval may be needed if the generator will be visible or noisy.

– Historic districts often have additional restrictions on generator appearance and placement.

– Make sure your home insurance covers generator operation if required by your policy.

Check with your local building department on the exact permit regulations in your jurisdiction. Failing to get required permits can jeopardize insurance coverage and lead to fines.

Can I Run a Generator While I’m Not Home?

It is not recommended to run gasoline-powered portable generators when away from home due to the risk of carbon monoxide buildup and fire hazards if malfunctions occur. Here are some exceptions where it may be permissible:

– Installed natural gas standby generators can run unattended since they don’t have the same CO risks.

– Dual-fuel generators using propane instead of gasoline have lower CO emissions.

– Models with CO shutoff monitors will stop automatically if CO levels get dangerously high.

– Outdoor generators may be safer to run alone if located away from the home.

– Ask a neighbor to periodically check on a generator running at your vacant house.

Even with proper precautions, all unattended gas-powered generators still pose some risk. The best approach is to turn the generator off before leaving the house or have someone frequently stop by to monitor it.

Conclusion

Installing a generator in your garage provides convenient emergency power, but also comes with substantial safety considerations. With proper precautions like venting exhaust outdoors, limiting fuel storage, and following fire codes, generators can be safely operated in a residential garage. Carefully consider all risks and regulations before connecting a generator indoors to ensure the safety of your home and family. Licensed electricians should assist with any generator that will connect to your electrical system. For intermittent use, portable generators kept outdoors are ideal to avoid carbon monoxide dangers. With the right guidelines, your garage generator can be an invaluable asset when you need it most.