Garage Door Insulation Calculator
An uninsulated steel garage door is about R-2. Enter your door size and panel layout to see how many kit pieces you need and what R-value you'll end up with.
Your project
Your results
- Door area
- 112 sq ft
- Panel sections to fill
- 16 sections
- Retail kits needed
- 1 kit
- R-value added
- R-3.9
- Approx door R-value after
- R-5.9
- Material cost
- $31
4 rows × 4 sections wide (typical)
Most kits cover about 112 sq ft (one 16×7 door)
Estimates use typical US material and labor pricing. Confirm quantities against the coverage chart on the bag before you buy.
Gear for this job
Garage Door Insulation Kit
Reach Barrier Garage Door Insulation Kit, Reflective, 8x8 Single Door
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SmartGARAGE - Reflective Garage Door Insulation Kit (Black)
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NASA TECH White Reflective Foam Core 2 Car Garage Door Insulation Kit 18FT (WIDE) x 8FT (HIGH) R Value 8.0 Made in USA New and Improved Heavy Duty Double Sided Tape (ALSO FITS 18X7)
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Reflective Attic Insulation Roll
AtticFoilㅤ – SuperPerf Radiant Barrier – 45” Wide / 1500 sq ft | Tearproof Breathable Lay-Over Foil Insulation with Large Perforations–Designed for Use Directly Over Attic Insulation
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Double Bubble Foil Insulation Roll 24" x 125' Radiant Barrier | Reflective radiant barrier for attics, roofs, walls, garages & HVAC. Aluminum foil blocks radiant heat;.
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Ultra Heavy Duty 10mm Reflective Insulation Roll - Premium Foam Core Radiant Barrier for Energy Conservation -Commercial Grade Soundproofing Thermal Shield for Indoor and Outdoor (24" X 25')
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Weatherstripping Door Seal
Holikme Weather Stripping Door Seal, Shower Door Seal Strip,1.8" W-33Feet | Flexible Door Seal, Seals Gaps up to 1.2", Helps Reduce Air Leaks & Dust, For Doors & Windows
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Ninsula 33Ft Door Weather Stripping, (1/2in x 1/4in), Strong Adhesive, Sound Proof, Door Insulation, Weatherproof Foam Tape for Doors, Weatherstripping for Doors Frames, Windows
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Ravinte Weather Stripping Door Seal, Q-Shaped Kerf Foam Strip, 26 FT, Black | Push-In Door Weather Stripping, No Adhesive, Fits 0.35 to 0.59 Inch Gaps, Door Frame and Jamb Seal, Blocks Drafts and Noise
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How this calculator works
- Door area = width × height
- Kits = door area ÷ kit coverage (about 112 sq ft)
- R added = R-per-inch × thickness
Frequently asked questions
Is insulating a garage door worth it?
If the garage is attached, heated, or has rooms above it — yes. It typically drops garage temperature swings by 10 to 20 degrees and cuts noise noticeably.
Will insulation make my garage door too heavy?
Foam board and reflective kits add only 10 to 20 lbs, which most springs handle. If the door feels heavy or won't stay half open afterwards, have the spring tension adjusted.
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Door area
112 sq ft