Sizing Climate Control

I recently chose a manufacturer and design for my heater and air conditioner.  They offer different size models based on cubic feet of space.  I am looking at 200 cubic feet of area plus 1000W of heat dissipation from equipment and 400W of heat dissipation from occupants.  The question came up about the design for insulation.  Right now we have R-26 for half the floor (R-10 on the other half but that can be increased if there is room in the avionics bay), R-7 average on the walls, and I suppose I could put batting up in the peak which is just airspace anyway.

The following is specific to my location. You can get your own recommendations by visiting their website.

R-Value Recommendations for New Buildings

Heating System: Natural Gas Furnace
Cooling System: Electric Air Conditioning
First 3 digits of ZIP code: 662
Location: Shawnee, KS

Wood-Framed Building
Insulation Location R-Value* Notes
Attic 49
Cathedral ceiling 38
Floor 25 Over unheated, uninsulated space.
Wall sheathing 5 It is important to use both the insulative sheathing and cavity insulation recommended. Insulative sheathing may be placed outside of wood sheathing product, or special braces can be used.
Wall cavity 15
OVE wall cavity 21 This recommendation assumes that a 2×6 wall can be built for the same cost as a 2×4 wall, using a careful design procedure called Optimum Value Engineering (OVE). Discuss this option with your builder.
Concrete or masonry wall 15.6 Insulation should be placed on the exterior side of an above-grade wall.
Band joist 30 A band joist is a part of a floor joist system (see Fig. 1). This part of the exterior wall must be insulated before the floor is installed.
Basements and Foundations
Insulation Location R-Value* Notes
Slab edge 8 Extend the slab insulation 2 feet below ground level.
Crawl space wall 25 Crawl space walls are only insulated if the crawl space is unvented and the floor above the crawl space is uninsulated.
Basement wall exterior 12 Exterior insulation on a below-grade wall is used only if you choose not to insulate the interior side of your basement wall.
Basement wall interior 11 Interior insulation on a below-grade wall is used only if you choose not to insulate the exterior side of your basement wall.
Metal-Framed Building
The recommended insulation levels for metal frames will not necessarily give you performance as good as the recommended levels for a wood-framed building. Please see the discussion about Design Option: Metal Framing.
Insulation Location R-Value* Notes
Floor 25 Over unheated, uninsulated space.
Attic cavity 49
Wall sheathing 10 It is important to use both the insulative sheathing and cavity insulation recommended. Insulative sheathing may be placed outside of wood sheathing product, or special braces may be used.
Wall cavity 15

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