First off I apologize for the wind noise. Needless to say it was windy that day.

I spent a lot of time looking at other people's videos and getting ideas, so I want to give back some of that by showing my generator shed for my WEN GN875i inverter that I have setup for whole house backup. I designed it in Sketchup so that I could get the dimensions exactly as needed and maximize the use of materials.

The high cfm exhaust fan provides fantastic airflow, which allows me to run the generator with all doors closed even in summer. The Rockwool Safe and Sound along with the intake baffle drastically cut down on the noise level. Of course there are a lot of small details I left out of the video for time's sake, but hopefully these are enough to give you some ideas for your project.

I didn't build the shed for the sole purpose of sound insulation. I built it to provide a reasonably secure place out of the weather to store it where I can also run it from during all types of weather. Sound insulation is a by product and bonus.

Here is a list of specific materials I used:
My Generator https://wenproducts.com/products/wen...
US Carburetion Motor Snorkel Kit (trifuel) https://motorsnorkel.com/conversionk...
Natural Gas hose https://www.amazon.com/gp/product/B09...
Additional Quick Disconnect https://www.amazon.com/gp/product/B01...
Rockwool Safe and Sound https://www.lowes.com/pd/ROCKWOOLSAF...
Foam Board Insulation https://www.homedepot.com/p/RTech1...
50amp Generator Power Inlet https://www.amazon.com/gp/product/B08...
Exhaust Fan https://www.amazon.com/gp/product/B08...
Exhaust Tubing https://www.ebay.com/itm/143629121740
2” Malleable Iron Pipe Flange https://www.acehardware.com/departmen...
2” Compression Coupler https://www.lowes.com/pd/SigmaElectr...
Rubber Exhaust Gasket https://www.amazon.com/gp/product/B01...
Fiberglass Exhaust Wrap https://www.amazon.com/gp/product/B01...