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Community and Q&A

Manual J, D, S

Kasey Doggett | Posted in Mechanicals on

I am working on a major remodel of my 1950s house. The existing ducts are metal. I am looking for someone who can advise me on whether my existing ducts are properly sized and who can perform a Manual J and S since I will be replacing the air conditioner and furnace. I am outside Houston. I would prefer a 3rd party consultant over an HVAC company. I see some companies perform this service without a site visit.

Do I need a local company who can come to the house or can they perform these calculations accurately without visiting my house based on the floorplan?

Any recommendations of who performs this service in the Houston area?

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  1. Expert Member
    Armando Cobo | | #1

    It is smart to have a 3rd party perform your load calcs. They can perform your calcs w/o visiting your house, although it maybe reasonable to see your existing system, and it maybe wise to do a duct leakage test though. They also need to be provided with all the information needed as well. Detailed set of plans and full specifications, including wall and roof assemblies with R-values for materials, window specs, dimensions and heights, lighting, appliances, etc. Provide pictures of the ducts and layouts if possible.
    Hopefully all your equipment and duct system is in the conditioned space, and your building envelope is tight; otherwise you maybe throwing money out of the window.
    Check in Waco, I know those guys know their business. I don't know any company in Houston, but you can Google for HERS Raters in Houston.

  2. GBA Editor
    Martin Holladay | | #2

    It's possible to have the work performed by a consultant who lives outside your area. For more information on this topic, see Who Can Perform My Load Calculations?

  3. Richard McGrath | | #3

    Try Energy Wise . They get it for sure

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