Thoughts on soffit and roof vents needed for new shack being built

[claystroup]

Getting close to finishing the soffits and roof on my new 12 x 18 shack I am building. Going to have 12" wide overhangs with 3/8" rough sawn plywood soffit material. Thinking of cutting in the small metal soffit vents on each side. I also plan on installing a 12" x 18" gable end vent on the back wall of the building behind the evaporator. I personally don't like ridge cap vents for the roof and would prefer to add 2 metal can vents on the side of the roof opposite of the side the chimney will exit on. Thoughts/suggestions?

[maple flats]

Make a cupola, that is by far the best way to vent all of the steam generated boiling sap into syrup. The only other good way is to have hoods on the pan and vent the steam thru steam stacks. Even a 2x5 flat pan, when you get boiling properly will fog the shack if you don't have a cupola. In fact, do you think you might someday grow into a 2x6 evaporator with 2 pans? If yes, make a 2x6 cupola now.

[whalems]

you will need a lot more venting then just soffit vents and gable end vents to get rid of all the steam. build a copula or use steam hoods and vent out.

[tcross]

are you trying to vent the steam with the gable end vents and soffit vents? if so, i don't think you will be happy with it's performance! if you're adding them to the building to cool the roof... is your roof insulated and is it shingles or steel. if it's not insulated, you don't really need any of the vents... especially if you have a steel roof. the vents are basically only to cool the roof.

[Pdiamond]

Clay, I think I know what you are talking about. You want to have air flow when the building is closed up, right? I have vents on my 12 x 16 sugar house on either end. Just make sure to put screen on the inside to keep the hornets out.

[claystroup]

I should have qualified my original question. My thoughts were about proper ventilation for the 10 to 11 months of the year when not sugaring. I am building the shack with a 3'6" x 6'00" cupola which will have opening doors on both sides for when I am boiling. The roof boards are 1" x 12" rough sawn pine topped with 15 pound felt paper and the 250 pd/square Certainteed Landmark shingles.

[maple flats]

In that case maybe just gable type vents might be fine. I have no vents, but my sugarhouse is not that tight.