Tom Kraeutler's Home Improvement Tips & Tricks

We have a Cape Cod styled home with attic vents on each end of the attic, along with a ridge vent.  The attic is insulated.  These vents are very helpful in the hot summer.  However, in the winter the upstairs is very cold.  I want to cover the vents in the winter when the air doesn’t need to flow through like in the summer.  Your thoughts?
jwflower57

While a drafty house is a bad thing, drafty attics are actually a good thing!  Here’s why:  Attic insulation works best when it is dry.  In the winter, attic insulation can get damp from humidity that works its way up from the heated spaces below.  If you allow just 2% moisture to get into fiberglass insulation, the R-Value (resistance to heat loss) goes down by a whopping 33%!  Having plenty of attic ventilation means that the moisture can dry out and the insulation remains effective.

For the most effective ventilation, I recommend continuous soffit and ridge vents.  Air will enter the attic at the ridge, run up under the roof sheathing when it carts heat away in summer and moisture away in winter, and exit at the ridge.  This 24/7 ventilation solution is far more effective than any other type of mechanical or passive ventilation solution.

A Cape Cod home with a partially finished second floor is particularly difficult to insulate.  However, I can offer one trick of the trade.  Make sure that the joists (first floor ceiling joists/attic floor joists) between the floors are sealed at the ends so that cold air which gets into the attic crawlspaces does not pass through between the 1st and 2nd floors.  To access these areas, open the doors to the attic crawlspace at the eaves and look down.  These are the open areas of the joists which must be blocked.  Use foam insulation cut to fit in between each open joists to stop air flow across the first floor ceiling.

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• #3 Comment from dorkevskaggs 
  9/22/07 11:53 PM | Permalink

  I think the ridge vent is NOT a good idea. I don't like ours at all, as we don't have a basement so all of my things are stored in the attic. Wish I could put the roof back to the old way.
  
  In the summer it is like a oven up there, NO air circulating, just hot air sitting there. At least with those whirly things on the roof it sucks the air out on a breezy day.
  
  In the winter the snow is blowing in on my stuff stored in the attic. Last winter I stuffed newspaper in as much of the ridge vent I could reach. I will do it again this winter. I just have to remember to remove it in the spring.
  
  I guess it work's for some and not for other's.
• #2 Comment from jasrfranklin 
  10/16/06 1:49 PM | Permalink

  I own a 19056 Arts & Crafts home. Like the cape Cod described above,  the attic is only vented at the ends and there are no soffit vents. Should I install these? Or, perhaps some solar electric vent fans?
  
  Also,  I'm looking at installing a ridge vent, since I live in Alabama and the 2nd floor gets very hot in the summer.
  
  I know I need insulation, too , since this house has none. It was built when there was no such thing, is lath and plaster, but was sheet-raocked by a previous owner.
  The cfross ventilation is quite good in summer, if you open windows on both sides of theh ouse and run a window fan at night.
  
  THanks
• #1 Comment from toliveischristtg 
  10/15/06 12:39 PM | Permalink

  I have been trying to find a way to keep my electric bill down. Are the any tips on what to do? Can you or somebody give a listing on this issue? Thank you.