Draft and wind

[mainemac]

We have some strong breezes today maybe 20-30 mph and I had a harder than usual time starting the fire.
Anyone else notice more trouble on breezy day.
(I do have a SS liner to the top with a cap to minimize this)

Tom

 

[brokeburner]

sometimes when im choked down with a good full box. Ill get a gust of wind and a puff of smoke will come out of the cracked primary

 

[albertj03]

I'm in Southern Maine and the wind seems to increase my upward draft. I had no problem getting the fire cranking this morning and it has burning very nicely with the primary air cut off all day. I have a masonary chimney with clay liner starting in the basement of my 2 story plus basement colonial.

On a side note, I've seen two trees blow down off to the side of my driveway. One was an old rotted poplar and one was a small pine tree.

 

[LLigetfa]

Chimney placement and leaky homes can have draft problem due to wind. Opening a window on the side of the house facing the wind can help. Whirlybird vents can be problematic if there isn't enough intake vent at the soffit and the house leaks to the attic. Leaky windows on the leeward side are also a factor.

 

[rustynut]

score one for that OAK !
didnt have one on the last stove and had draft problems.
Seems that this system is much more balanced using the OAK
Whatever pressure the chimney is seeing , the intake is also seeing.
Just wanted to share my thoughts on this...........
rn

 

[cmonSTART]

I added another 3 foot section of chimney on this fall to ours and noticed a huge benefit today first hand. On windy days we used to get down drafts down the chimney which would make starting a fire very difficult. Today was such a day and it didn't really matter at all. Extending the flue moves it out of a positive pressure zone which can form in certain areas around the house envelope. Very cool to see it first hand!

 

[LLigetfa]

I added another 3 foot section of chimney on...

Ja, I need to do the same thing. Didn't want to have to brace the chimney and wanted to have it in easy reach for top down cleaning.

 

[grommal]

Whether wind increases or decreases draft depends on the specifics of exactly which direction the wind is striking the chimney top and exactly what the geometry of the chimney top is. A straight lateral wind blowing across a chimney without a cap would produce an updraft from the Bernoulli effect. If wind blows too much downward into an uncapped chimney, that can create a downdraft. The particulars of the shape of chimney caps can have a large effect on this, though. A typical cap with roof and screened sides can behave very differently from different wind directions if the cap has been bent so the roof is tilted. Some caps are designed to produce the Bernoulli updraft regardless of wind orientation (VacuStack is one example). Nearby roofline or tree obstructions can have a large effect on the wind direction right at the cap, too.

Fortunately, ours seems to be one where high winds always produce updraft.