10+ DIY Generator Shed Ideas and Plans

Generators come in various shapes, sizes, and power ratings, but they all have one thing in common; they provide electrical energy when required. The greater the power rating, though, the larger the generator, so if you’re looking for a place to store and protect your generator, consider building a generator shed. If you’re not sure how we’re here to help!

There are numerous possibilities on the internet for converting manufactured plastic sheds or DIY sheds into generator sheds. Some key things to plan for are adequate ventilation, heat, noise, and managing the generator’s exhaust. A safe electrical connection to an anti-feedback switch or box is also very important too.

In this guide, we take a look at different online generator shed ideas and plans and provide a brief overview of each. We provide you with some ideas and explain what is required when building a shed for a generator, as well as some choices and plans. Our aim is to present you with options so you’re better prepared when you decide to build your own generator shed.

10+ DIY Ideas and Plans on How to Build Generator Shed

Each of the designs discussed below offers different ways to enclose, protect, and secure a generator. The types of materials used vary and can often be exchanged for others, while the skills and tools required are fairly common. The plans can be used as is, or as a starting point for your own unique design. Some concerns raised regarding noise, electrical back feed, and also CO2 gasses are addressed too.

1. DIY Generator Enclosure Shed

This plan explains how to turn a prefab plastic shed for trash can storage into an insulated generator shed with built-in ventilation and exhaust. It discusses how to protect the plastic sides, doors, and lid from heat generation with reflective insulation which will also reduce noise output, as well as fire risks. It even has a remote self-start system, so the generator can be controlled from within the home.

The shed sits on a concrete pad to prevent settling and the generator rests on a thick rubber mat to minimize vibration. The electrical connection to the supply panel is also discussed with warnings about back feed, and to ensure electrical codes are followed. The site includes links for the plastic shed, remote control battery start generator, attic vent fan, insulation, and even the fire extinguisher.

2. DIY Generator Enclosure

This plan is for a 4’x4’x4’ wooden shed which is heavier and typically stronger and more customizable than a plastic shed. The shed has 2×4 framing and is sheathed in OSB, and painted on the exterior. 2×4 slats that make up the floor have about a 1/4” gap between each other to improve airflow. The floor is fastened to three 4x4x4s that keep the box off the ground and act as skids so the box is easier to move if necessary.

There is an attic exhaust fan and intake venting, plus an exhaust port for the generator. To monitor heat buildup during operation, there is also a remote sensor that links to a base inside the house.

The shed has double doors that open one whole side for access and the roof is hinged so it can lift for easier refueling or additional venting. There is also a noise reading that demonstrates a 10dB improvement when the shed is operating and closed versus open and operating.

3. DIY Generator Shed

This plan demonstrates the conversion of a Suncast plastic shed into a generator shed. The shed rests on and is fastened to 4” thick patio blocks. This is a fairly simple conversion and doesn’t use any insulation or reflective material. There is a hole in the wall with a weatherproof cover through which the 50AMP power cord can be inserted and connected to the generator.

An attic fan with a thermostat provides hot air exhaust once the generator is running and is on the same side as the generator exhaust port. A 16”x16” static vent on the opposing side allows cool air in. A 3/4″ pipe connects to the generator exhaust and vents through the shed wall.

To prevent any melting of the plastic at the exhaust pipe, a piece of Hardie board siding was inserted to protect the plastic. The site includes links to some components used for the shed build too.

4. Generator Shed Plans

A 57” x 84” x 78” wooden storage shed with a lift-up lid and double doors makes an excellent storage space for securing and protecting a generator. All framing for this shed is 2×4 with the floor and lid covered in 3/4” plywood, and all sides with exterior grade paneling. Material and tool lists are included, and the layout and all cuts are noted, including trim work. The lid is also shingled to protect it from the elements.

The plan is two parts with easy linkage between the two. The shed as built is for storage only but is a basic shed design that can be customized to meet most requirements. Venting and insulation or soundproofing could easily be added, along with a muffled exhaust port and fan, so the generator could be operated from within the closed shed. An easy DIY shed that could be completed in a weekend or a week, depending on available time.

5. How to Build a Generator Quiet Box

Generators provide backup or emergency power, but they’re usually 75 to 85 decibels loud when operating. This plan is not only about building a generator shed, it also includes sound canceling improvements that significantly quiet the sound to around 60dB.

The plastic lift-top garden shed sits on small patio stones and a thick rubber mat was used to cover the floor and decrease vibration. This plan includes links to most of the components used, plus a parts spreadsheet.

An intake vent supplies cool air on one side and the other side has a port for cords and the propane supply hose for the generator, a power exhaust fan, and the muffler exhaust opening. Rigid rock wool panels were used to provide sound insulation to the interior surfaces of the shed, plus, its fire resistance is good to 2150°F.

The muffler exhaust pipe is a flex hose wrapped in insulative tape and a motorcycle muffler was added to the end to further reduce noise. Two insulated baffle boxes were also added over the air intake and exhaust vents to further mitigate the noise.

6. Generator Shed Build

This plan explains how to cancel generator noise using rock wool insulation, vent baffles, and a homemade muffler exhaust. It uses a plastic utility box shed with double swing doors and a lift-up lid. Rock wool insulation lines all side surfaces of the shed to protect from heat and reduce noise.

Reflective insulation was used to line the lid. There’s an intake vent and an attic exhaust fan vent to maintain airflow and reduce heat in the shed during operation. There is also a port for cords to pass through and an exhaust port for the generator.

The two vents are covered with baffle boxes to minimize sound. The generator exhaust goes through a homemade muffler that significantly mitigates noise. The results drop the sound from 92dB when the shed is open to 70 when closed at a distance of 2 feet.

The noise at 25 feet from the shed is only 59dB, making it quieter than many air conditioning units. A key recommendation from this plan is that the generator shed be away from windows and doors to prevent deadly CO2 gas from entering the home.

7. Custom Sound Insulated Generator Shed

A wooden 4’x5’ shed designed to protect and secure a gen set, and to minimize noise. The site includes links to most of the materials used in the construction too. Set on a concrete pad, the 2×4 framed shed is sided with exterior grade LP SmartSide and insulated with rock wool insulation.

The shed has access doors on the front and back to make connections and servicing easier too. The ambient noise level when off at 2 feet is about 43dB, 91dB with doors open and operating, 74dB when closed up, and 67dB at 5 feet.

A 20” attic exhaust fan removes heated air and draws fresh cool air in from a vent on the opposing side. The intake vent is baffled to mitigate sound transfer, and a hinged magnetic trap covers the opening to prevent bees and other critters from moving in. The generator is hardwired to the house with appropriate back feed safeguards.

A small solar panel trickle charges the battery so it is always ready. The exhaust is modified and wrapped in fiberglass insulated tape to reduce heat transfer and goes through a protected port in the shed wall.

8. Cedar Generator Shed

A 2×4 frame fastened to a concrete pad and clad in cedar makes for a nice addition to the yard. A drop front and lift-up roof provide access and pneumatic hinges assist in lifting and holding the lid open. Cement patio stones on edge create a heatshield on the muffler side of the generator.

Reflective-backed rigid insulation also helps with heat protection and noise reduction on the rest of the interior surfaces. When operated with the lid and door closed the sound is much quieter than when open.

An attic fan vent draws fresh air in from a vent on the opposing wall to create cross-ventilation. The fan also removes exhaust fumes as there is no port for the generator exhaust. A thermostat, however, controls the speed of the fan to prevent heat buildup in the shed during operation.

The roof is finished with corrugated steel roofing, adding a bright pop to the aesthetics. The power cord to the house passes through a hole in the shed side and plugs into a transfer box on the house.

9. Generator Shed With Noise Isolation

Building a quiet shed for a generator begins with location. This plan recommends placing the generator shed at least 20 feet from the house to isolate noise and vibration. The shed sits on 2” concrete patio stones.

The 2×4 floor was covered with 3/4″ plywood, and the 2×4 walls were sheathed in 1×6 rough-cut pine. There are two doors on one side for access, and the shingled roof lifts too for access. Two gas struts assist in lifting and holding open the roof.

Cross-ventilation is handled by an attic exhaust fan on one wall and a vent on the opposing side. All interior surfaces are covered with rigid rock wool insulation, and the sides and back are also covered with cement board for further protection and noise reduction.

The generator exhaust has an extension through the wall and connects to a noise-isolating muffler. The noise is significantly reduced when closed. This plan also includes links to different components.

10. Generator Storage Box Under the Deck

This plan discusses a fully enclosed 2×4 framed, 1/2″ pressure treated plywood sheathed generator shed built under a raised deck with easy access through a hinged door/wall. A door on the opposing wall provides cross-ventilation. It can be opened from the front using a rod operated from the front. This allows the generator to stay dry if raining, otherwise, the generator is pulled out for use if the weather permits. The roof is also sloped to shed any moisture dripping between the deck boards.

The power cord is attached to the generator once it’s started and then attached to a transfer box on the house. There is no attic fan to move air or any other venting or insulation, but they could easily be added to this design. The door is also locked with a deadbolt to deter theft.

The site includes a recommendation to build the shed larger than the generator to allow air movement to prevent overheating and burning the deck and house down. There’s an additional recommendation about care when fueling.

11. Generator Shed From Scratch

A plastic shed set on patio pavers forms this generator shed. Self-adhering reflective backed automotive matting is used to protect some walls. Fire-resistant Hardie backer board is used where the generator muffler has close contact with the plastic walls.

A galvanized dryer vent with a short length of pipe provides the port for the generator exhaust. To protect the opening for the propane supply, a flip cover exterior receptacle cover is used.

To prevent overheating, an attic exhaust fan and two floor registers for intake vents provide air circulation. There is no opening for the power supply cord, but one similar to the propane supply cover could easily be added. The shed decreases the noise level when closed, making it more tolerable in urban settings.

Conclusion

Building a generator shed is a great way to protect your generator from the elements and theft and ensure it is ready when needed. The shed should be larger than the generator to allow for airflow and maintenance.

Start with a base that minimizes vibration, so concrete or framed with a rubber mat. Whether using a framed shed or a manufactured plastic one, plan for an electric start generator sized to carry the load required. Also, think about adding a solar trickle charge to keep the battery topped up.

To minimize noise and heat, consider rock wool insulation and/or automotive thermal matting with reflective backing. Use a high CFM attic exhaust fan and a large grill vent for the intake. Add a thermostatic control on the attic fan with electric backup to operate after the generator is shut off to decrease heat in the shed.

To further reduce noise, consider adding baffles over the air intake and exhaust to mitigate noise and a muffler system to the exhaust, especially if the generator is near the house or you have neighbors. Hopefully, we’ve provided you with some new ideas to consider for your generator shed.