+ Reply to Thread
Results 1 to 4 of 4
  1. #1
    Join Date
    Aug 2013
    Posts
    9

    Default Forced air in Los Angeles - Attic or crawl space?

    House was built in 1923, and has no heating or cooling to speak of. While this is LA, between the spacious crawl space and utter lack of insulation, we tend to get the same temperature inside as outside. We plan to insulate the attic in the future, but we also want HVAC (both for our comfort and for resale down the line.) We'll be in the house for 10 years, though.

    We've spoken to a few HVAC companies, and they're split on whether we should run ducts in the crawlspace or the attic. Pros/cons seem to be that we can avoid craning a compressor up onto the roof if we crawlspace it, and we can get better air circulation with ceiling vents instead of floors, but we'll have a noisy compressor on the roof, and we'll have to cut vents in lath and plaster ceilings, which risks big chunks falling out.

    We have 2-3 foot crawl space, so I'm more interested in just using that, but I'm worried that floor vents won't do as good a job of circulating air. This is LA, so we don't have HUGE heating/cooling needs, but I don't want to lose efficiency with bad duct placement. Does anyone have any experience with heating/cooling in SoCal who can tell me what their experience has been like?

  2. #2
    Join Date
    Jul 2010
    Location
    SoCal
    Posts
    6,699

    Default Re: Forced air in Los Angeles - Attic or crawl space?

    "We tend to get the same temperature inside as outside" - that's not good enough. What if the outside temp dips to 45 at night, are you comfortable with 45 inside? Insulate asap.

    I'd choose the roof as the location for a combo a/c-heater unit. Today's units are quieter and more energy efficient than before. Make sure the rafters can support the weight and if not, beef them up.

    Raising a unit to the roof is much easier than squeezing one into a crawl space.

    Cutting the ceilings for vents and then adding blocks between rafters and around them will give you all the ceiling support you need. No falling ceiling chunks. You just have to have workers who know what they're doing. That's where SUPERVISING them comes into place. With proper supervision, you'll get nice clean work.

    You want the ducts in the attic, not in the crawl space. You'll be using the a/c more than the furnace, and since cold air goes down, the ceiling is the best location for the vents.

    Choose your contractor carefully, not only for proper installation, but also for the correct calculations when determining which unit is right for you. My choice: Rheem.

    If you're planning on selling your house, most potential buyers will choose a house with a/c over a house without.

  3. #3
    Join Date
    Sep 2012
    Location
    Boston
    Posts
    1,004

    Default Re: Forced air in Los Angeles - Attic or crawl space?

    i agree with everything dj said.

    only comment i have.....tell them to put the air handler in the attic and the compressor in the yard. that's how it's done around here.

  4. #4
    Join Date
    Jul 2010
    Location
    SoCal
    Posts
    6,699

    Default Re: Forced air in Los Angeles - Attic or crawl space?

    "only comment i have.....tell them to put the air handler in the attic and the compressor in the yard. that's how it's done around here.[/QUOTE]"

    We have that arrangement too, compressor in the yard , furnace in the house or garage. Not so much in attics - we don't have steep roofs and tall attics. The great thing about "combo" units is that in small houses with 1 car garages, there is no space for the furnace, so putting it on the roof is a space saving idea.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •