Ventilation holes in a homemade incubator

[SoJoChickens]

I recently completed an incubator build using a styrofoam cooler. With my automatic turner it holds a dozen chicken eggs so it is not real big (perhaps 14" wide x 18" long x 14" high on the interior). I have been able to maintain a very stable temperature and humidity setting in the incubator but I'm not sure what kind of ventilation holes I need (how many and where to put the holes). It is a forced air design. I don't know if it makes a difference or not but I live in a very dry climate (desert) at high altitude (6,000 ft). I would appreciate any recommendations for ventilation. Thanks!

 

[Skipper81]

I would follow the little giant design for ventilation it works pretty good
9 tiny holes on bottom
8 tiny holes on top
2 dime size holes on top also

 

[SoJoChickens]

Thank you! So the smaller holes (they look to be about 1/4" diameter) are always open and the larger holes have plugs that can be used as needed. Is that correct?

 

[Skipper81]

That’s correct

 

[SoJoChickens]

Thanks Skipper81! I'm trying to learn everything I can to achieve good hatch rates.

 

[Egghead_Jr]

1/8 inch not 1/4. The large holes are 1/2 inch. My incubator only has the one large hole top. 8-10 1/8 inch bottom.

 

[SoJoChickens]

Thanks! I would have made the holes too big.

 

[Mosey2003]

You can use a bamboo skewer to make the holes on the bottom. Angle them slightly inward towards the top, I'd put at least three on each side. They should come through just slightly above your water level. Then the top ones larger, yes. You can either make plugs or use something that you would slide across over the top of it, even a heavy piece of metal, if you aren't going to disturb it much, could be laid across the top ones.

 

[SoJoChickens]

You can use a bamboo skewer to make the holes on the bottom. Angle them slightly inward towards the top, I'd put at least three on each side. They should come through just slightly above your water level. Then the top ones larger, yes. You can either make plugs or use something that you would slide across over the top of it, even a heavy piece of metal, if you aren't going to disturb it much, could be laid across the top ones.

Thanks. I'll give that a try when I get home. I started using a drill bit but it made a mess of the styrofoam! I also thought of trying to heat up a metal skewer and melting the holes but I'm afraid I would melt more than I want and the holes would be too big.

 

[Egghead_Jr]

Heating a skewer would work well. I have one large hole top and leave open all times. It needs to be open last few days of hatch so most just leave open entire incubation.