Covered Roof Whirly Bird
If you have whirly birds like this on your roof,
it's a good idea to cover them in the wintertime, to prevent heat loss.
This keeps your attic warm and helps lower heating costs in the winter.
If you leave them uncovered, they will continue doing
their job and that's moving hot air out of the attic.
The only problem is, that you need to remove the
covering in the summertime.. Don't forget.
These whirly birds are used for attic ventilation and are relatively
easy and inexpensive to install.
Whirly birds have been around for years, even though I don't see very
many of them installed anymore.
I have seen these leak during heavy rains.