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I'm building a house and doing the HVAC myself I want to…

I'm building a house and...
I'm building a house and doing the HVAC myself I want to know what size equipment to use and the size ducts I need is anyone on ASK capable of the calculation. Thanks ....
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Answered in 1 hour by:
10/19/2017
Regan Land
Regan Land, HVAC Technician
Category: HVAC
Satisfied Customers: 768
Experience: Over 20 years of experience, NATE Certified, Licensed HVAC Contractor, Certified IAQ Specialist
Verified

Hello and welcome to Just Answer. My name is ***** ***** I'll be happy to assist you today. What you need is a full house Manual J heat load calculation to determine size of equipment and a room by room load calculation to determine how much CFM should go into each room. Then you will size your duct accordingly. Contractors used to base the HVAC size on square footage (typically 1 ton per 400-600 square feet depending on insulation) - with new home being built tight and higher efficiency HVAC systems that require more run time to remove latent heat (moisture), it is imperative to size the system properly. A Manual J calculation will take into effect wall area and direction, window area and direction, insulation, construction materials, roof color, floor type, fireplaces, etc into effect to give you the total BTU heat gain and heat loss. Then equipment will be sized accordingly. There are Manual J calculation programs and calculation sheets on the internet that will allow ou to do your own, but it is highly recommended to at least pay a licensed HVAC contractor for this service. Hope this helps!

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Customer reply replied 9 months ago
is there a site I send a floor plan and specifics on windows,doors etc and they tell trunk size and equipment size

Here's a couple I found:

https://www.energyvanguard.com/service-category/hvac-load-calculations

https://homeenergypartners.com/hvac-design/ - Costs .08 cents per square foot ($160 for a 2000 sq ft home)

You could also do your own calculations for free: https://www.coolcalc.com/products/manual-j

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Home Energy Partners will do the whole house Manual J and room by room Manual J plus the Manual D duct design for .20 cents per square foot ($400 for a 2000 sq ft house).

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You could also see if a local HVAC contractor would do these calculations for less. You may find one that will charge $150 for Manual J and duct design.

Regan Land
Regan Land, HVAC Technician
Category: HVAC
Satisfied Customers: 768
Experience: Over 20 years of experience, NATE Certified, Licensed HVAC Contractor, Certified IAQ Specialist
Verified
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Regan Land
Regan Land
Regan Land, HVAC Technician
Category: HVAC
Satisfied Customers: 768
768 Satisfied Customers
Experience: Over 20 years of experience, NATE Certified, Licensed HVAC Contractor, Certified IAQ Specialist

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