Air Conditioning - Effectively spending 1000$

To the point. Inside air condition uncomfortable despite 400$ utility bill.

- Pier and beam house, Dallas, Texas , built in 1967, 2400 sqft.
- ductwork runs through 2ft ventilated crawlspace. Ductwork not sealed but insulated. Tons of condenstion. Air flow apparent in crawl space from unsealed ducts.
- No moisture barrier in crawl space.
- return air ducts constructed of plywood in attic. not sealed.
- attic insulation covers to 1/2 - 3/4 rafters.
- no shade on roof. no radiant barrier in attic.
- 2 attic turbine type vents. soffit vents unobstructed.
- windows replaced 2008
- Inside humidity 50 - 60 %
- A/C unit relatively new 4.5 ton.

Where do I start in order to most effectively spend money in order to make my home more comfortable? Thanks for your time.

A few things I can throw in... making sure ducts are well sealed and insulated where necessary. Is the cooling even... ? Also do you know if your contractor did a heat/loss load (Manual J) calculation to properly size your unit? Clean air filter?

Since you already have a nearly new unit, you'll need a manual J done to check if it is correct size. Manual J will also calc amount of supply and return air flow each room needs.

This info in hand, contractor can remove all your bad ductwork and install new, correct, sealed and insulated.

Also, bring attic and crawl space upto current code.

I know nothing! Bought the house one year prior in this condition. The half of the house where ductwork returns are longest are considerably warmer than those close to the furnace. I assume that I have considerable air loss along those stretches. I was told by one company that sealing the ducts in the crawl space was not worth the time and effort. They would rather install new ductwork through the attic. I was also told however that this would be costly and it would take alot of months to recoup the cost of new ducting through decreased energy bills. I am a weekend warrior type of guy but I think with a proper schematic completed by a professional I could install the ductwork myself. We don't have a ton of money to throw at this problem. Would replacing ductwork be the most cost effective way to improve the air quality inside my home?

How should I begin to bring attic and crawl space up to current code? This is going to have to be completed in a stepwise fashion. I am betting that a total redo would cost around 10 - 15 grand without a new compressor. Does that sound right or a I undershooting. Also, If I get all that done, doesn't it make sense that I will still have a home constructed in 1967 with all the air leaks that go along with age.

It is a good estimate concerning retrofit ductwork only - Count the amount of diffusers supply and return - Take that number and multiply it by and average of 300 dollors. 10 runs x 300 = $3000.00. That will be close. It of course will be affected by what is called "Hard Access". That could increase by 30% due to 2 ft space to work in. More time means more money.

* I wouldnt recommend doing it yourself. There are a whole palithera of reasons why you should not.

Good luck and remember this delima next time you buy a house - Get the plumbing, electrical, and HVAC looked at by a professional independant of the inspector - You can see how it could save you $$$$$$$....!!!!

Time to hit the library, online and in person.

Here are a few links to start with.

http://www.grainger.com/Grainger/wwg/productIndex.shtml?search_type=brand&QueryString=ATCO&operator=refineSearchResults&originalValue=Duct%2C+Flexible&searchIndexId=1&typeOf=
http://www.atcoflex.com/
http://www.atcoflex.com/assets/pdfs/InstallInstructions.pdf
(http://www.atcoflex.com/assets/pdfs/InstallInstructions.pdf)

I would still suggest a load calc be paid for, and retained for referance in your project if you DIY.

Would replacing ductwork be the most cost effective way to improve the air quality inside my home?[/QUOTE]


To improve IAQ in the home you will need to seal return and supply duct. add VB on ground in crawlspace close vents. You still might need a dehumidifier to maintain under 55% rh in crawl. To reduce energy. Seal and insulate all duct. Remove RH from crawl to keep AC from having to work as hard.

You guys are good. Quick replies I appreciate as the computer is in a "hot zone" room. Is rerouting through the attic a good idea? I guess I would need a new furnace if I decided to do that. Should I even begin to attack this problem with 1000$. Or should I just throw a huge window unit on the hot side of the house and call it quits? Would attic vents or an exhaust fan up there decrease the temperature of the attic thereby making the house easier to cool. I am not currently looking to spend 10 grand as it would take 100 months at 100 bucks per month savings to recoup those costs. I realize that anything cheap would just be a patch job and would not address the real problem. By the way, these forums seem to be the best research on the web as you guys aren't trying to sell me anything. :D

What sort of complany could offer all services mentioned. VB, ductwork, crawl space seal? Do all A/C companies offer these services?

Any HVAC company with a IAQ department could.