What is a Manual J?

Manual J Components

The following are components that are calculated on a Manual J Report. Each item is compared to a set of climate data and given a heat gain and heat loss score.

The climate data on a Manual is as follows:

Summer Outdoor Temperature

Winter Outdoor Temperature

Summer Indoor Temperature

Winter Indoor Temperature

Design Grains

Cooling Relative Humidity

Daily Range


All of the above items are based on the jobsite address of where the new construction, addition, or alteration where the home is being built. ACCA Manual J 8 contains airport, climate center, and temperature collection center data for each areas across each state. You simply choose the climate data closest to your jobsite and move on to calculating the next section.

The components that are calculated in a Manual J are as follows:


Glass Doors


Solid Doors






Internal Load


Blower Heat


The components are all compared against the climate data in the top section of this Manual J blog post. On one side of the Manual J you will have the Sensible Cooling Loads and the Latent Cooling Loads. These measure the amount of heat gain the structure will have to contend with in your particular climate zone. The other side of the Manual J features the Heat Loss. This is your heating load. This is the amount of heat loss your structure will have during winter months when you might prefer to have the heat or furnace on.

Overall the Manual J is a great tool to measure the heat loss and heat gain totals of your home. We can create a Manual J for your in 4-6 hours and we charge $79 for any size plan. Email us your order number, pdf plans, jobsite address, and square footage to plans@manualjs.com to get your Manual J started today.

What is Manual S?

What is Manual D?

Review Date
Reviewed Item
Manual J Calculation
Author Rating
Software Name
Software Name
Windows, MAC, Linux, Android, Mozilla, Chrome, Explorer, Safari,
Software Category
Manual J Residential Load Calculation PDF

Email order number, PDF Plans, jobsite address, and square footage to plans@manualjs.com