Attic Fans (not Whole House)
I live in a cape cod home in Kentucky and my master BR is in the attic. There is duct work and heat/air but not as efficient as it probably should be to combat the heat of the summer. Winters are comfortable – a few cool spots and spring/fall are okay. Summer on the otherhand can be quite miserable. I have been told by the prior home owners that the attic has been sealed with spray foam insulation from the “great insealators” but the attic spaces have been sealed shut – small openings within the attic walls within several places in the bedroom but still not cutting the heat of the summer. I receive full sun most of the year due to only having small trees around the property. I was told an attic ventilator fan would do the trick, but after reading your reviews it doesn’t appear to be the case. Looking for best options to remove some of the heat from the roof during these summer months as the portable window unit is loud and disrupts my sleep but home AC can only cool the room to about 75 degrees without turning AC down below 64 at night for the entire house. I have also looked at having a separate unit up there but as of now, think my only option is the split unit with the ugly wall mount which I’m also trying to avoid. Any guidance would be appreciated.
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Replies
Genevieve,
First, you'll need to describe this bedroom a little better. You tell us that the bedroom is "in the attic," but (for most of us, anyway) an attic is, by definition, unfinished. It sounds like the top floor of your house has been finished (including insulation and drywall), and that is your master bedroom.
If I'm right so far, the next questions are:
1. Does your master bedroom have sloping ceilings or a flat (horizontal) ceiling?
2. Is there an attic above your master bedroom ceiling?
3. Are there any unfinished "side attics" behind kneewalls on the same level as your master bedroom?
One reason I'm asking these questions is to find out whether you have any ducts in unconditioned spaces. If you do, that's a problem -- ducts should be installed inside your home's thermal envelope if possible.
The best solution to your dilemma would be to discover why your central air conditioning system isn't keeping your bedroom cool. It's probable that the ducts are undersized. You may want to ask an HVAC contractor to inspect your system or provide advice.
If that doesn't work, I suggest that you use a separate air conditioner for your bedroom -- either a through-the-window unit or a ductless minisplit.
"I have also looked at having a separate unit up there but as of now, think my only option is the split unit with the ugly wall mount which I'm also trying to avoid."
Sounds like you're not enamored by the aesthetics of typical mini-split wall coils, but for not a huge up-charge you can get floor mounted units instead of wall coils. If you have knee-walls & sloped ceiling you could even cut into a kneewall and mount it roughly flush with the wall, provided you observe the manufacturers' minimum clearances. Alternatively, if you have a flat section of ceiling wider than 20" you could also use a ceiling cassette version roughly flush with the ceiling.
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But adding a mini-split is an expensive last-resort. It's probably going to be cheaper (and better) to lower the cooling load (more insulation, exterior window shades, etc) and improve the flow on the central air, as Martin suggests.