Just Need Paint and an Outtage

Got the generator box all finished. It really is quiet and runs cool. It's about as loud as the fridge inside the cottage. Plumbed to propane so the gas won't ever go bad. The roof is hinged in case the electric start fails and you have to pull start the thing. The exhaust is a water heater flue pipe wrapped in glass wool insulation then wrapped in aluminum high temp tape. I re-did the exhaust, it's double walled pipe going through the wall and extending out 12"---I was worried about exhaust heat so close to the fascia.

Sound In, Heat Out

The challenge is keeping the sound in and the heat out. I made an adapter coming off the muffler so I could channel the exhaust out of the box. I suppose I could get a better pic of how the adapter attaches; I wrapped the elbow with high temp aluminum tape for insulation and to keep the elbow from sliding around. The interior is all lined with foam board. The walls that face the house, have the studs turned sideways--that way there's room for insulation and sound transferring lumber doesn't go all the way through the wall.

Then, outside the foam board, there's a layer of fiberglass insulation. Even before putting all the vents in and roof on, it runs much quieter with a little sound barrier between the generator and the house. I walked AnnaMarie through the start-up procedure for the first time---she's able to manage it fine

A three inch duct will take the exhaust out. My adapter isn't a tight fit, I didn't want to create a backpressure issue (but I think 3" pipe for a short run won't be a problem)

Power Foundation

So the base is done. I like the effect of the concrete that was poured against the bubblewrap. Some of the cells filled with concrete, but if I ever did this somewhere that shows, I think I could be gentle enough so that wouldn't happen. I got the texture I wanted to absorb sound at least. I ran the generator. The transfer switch seems to work well, and I was able to power everything in the cottage. There's a slight flicker in the lights when you start up something with a motor, like the range hood or garbage disposal.

Generator Base

Just before I left for a week in Catalina with patrick's 8th grade class I got the base poured. I had to resist the temptation to strip the forms before I left--the concrete was still pretty green. You can see the sewer pipe elbows that will draw cool air in below the unit. I wrapped the inside of the forms with bubblewrap---the idea is walls with more surface area will absorb more sound than flat walls. We will see.