By our rough estimate, for a garage heated consistently throughout the winter, insulating four walls, garage doors, floor, and ceiling to R-19 would result in about $1050/year in energy savings!
Typical recommendations for exterior walls are R-13 to R-23, while R-30, R-38 and R-49 are common for ceilings and attic spaces.
Osb is the best option , but best advice someone gave me was prime the boards before you put them up . If you dont prime humidity will be an issue ( depending on where you live) . And painting the ceiling afterwards is a pain .
Types of Garage Ceiling Insulation
Depending on the climate in your area and the thickness of your ceiling joists, aim for a total R-value between R-13 and R-30.
Affordability: Drywall is one of the most cost-effective options for garage ceilings. It's inexpensive, making it an appealing choice for homeowners looking to stay within a budget while achieving a clean, finished look.
Painting Garage Ceilings: Best Practices
While you can use the same paint as the walls, a semi-gloss finish will work best for ceilings as it reflects more light and is easy to clean.
The garage shall be separated from the residence and its attic area by not less than five-eighth inch (15.9 mm) type x gypsum board or equivalent applied to the garage side.
By our rough estimate, for a garage heated consistently throughout the winter, insulating four walls, garage doors, floor, and ceiling to R-19 would result in about $1050/year in energy savings!
If the garage is heated, you will need a vapor barrier, otherwise you will get frost and mold. Some argue that the car itself will cause the garage to be heated, but this would only be the case if you left the car to warm up in the morning, otherwise it would not have the chance to warm the garage.
As a homeowner, learning how to insulate a garage requires proper preparations and safety precautions. The cheapest way to insulate a garage is by using do it yourself spray foam insulation.
Insulation plays an important role in cooling or heating your garage. While it is a common practice to insulate your garage walls and doors alone, neglecting the ceiling can reduce the effectiveness of your cooling or heating systems.
Glue-On and Staple-On Ceilings
If you're looking for an affordable option that's low maintenance and easy to install, consider a glue-on or staple-on ceiling. They're available in basic textures and elaborate designs and attach directly to the existing ceiling or onto furring strips attached to the ceiling.
By far the most common ceiling lining material is plasterboard. However, for a decorative ceiling you can turn to cladding. Cladding, by definition, is a decorative skin. There are many types of cladding which can achieve a timber look.
For 2×6 walls, you need an R-value of 19, and the recommended wall insulation R-value for all zones falls between 19 to 21. If you decide to insulate the ceilings, they should have a minimum ceiling insulation R-value of 30.
After the insulation is in place you will want to add a vapor retarder, sometimes called a vapor barrier, if you need one. Not every wall does. A vapor retarder is a material used to prevent water vapor from diffusing into the wall, ceiling or floor during the cold winter.
1- Is your garage attached or not to your house? If it is attached, it is best to choose a garage door with an R-value of R‑12 or R‑16. If it is detached and unheated, a lightly insulated or non-insulated door should be enough.
Exterior Garage Walls
Typically these will be constructed from standard 2-by-4 studs which will define the amount of insulation that you can have installed. You should be targeting an R-Value of R-13 or R-15 in these areas to properly maximize your insulation in this application.
“For minor projects, the absence of a vapor barrier leads to water intrusion, leading to an unstable foundation or a cracked slab.” The American Society for Testing and Materials (ASTM) outlines national standards for underslab vapor barriers.
For those that spend a lot of time in the garage or have some of their most valuable belongings in there, putting up drywall in your garage is definitely worth while. It adds protection, appeal and longevity to your garage as a whole.
R19 insulation is a thicker, more robust option—offering higher thermal resistance. Commonly used in colder climates, R19 is well-suited for 2x6 wall assemblies, floors, ceilings, and attics. Benefits: Provides superior thermal protection, contributing to lower energy bills and enhanced comfort in colder regions.
Insulating an unheated garage alone may not necessarily cause mildew, but the risk of mildew increases if there isn't proper ventilation. Insulation can trap moisture in the garage, especially in humid climates, creating a perfect environment for mildew growth.
The cost to insulate a 24' x 24' garage is $3,000 - $8,000. Garage size influences the cost of insulation. The 24'x24' garage will house 2 cars and some extra space for other purposes. The average cost to insulate a 24x24' garage with spray foam is $6,000.
You'll likely need a permit since this project may require soil grading to avoid drainage issues. Repairing your floor may be more cost-efficient than replacing it if grading is necessary. No permit may be required to hang drywall on exposed wooden wall studs in your garage.
If you're insulating your garage ceiling, you'll need a higher R-value. Why? The joists are deeper, so there's more space to insulate to create a sufficient thermal boundary. Your garage ceiling would likely be insulated in the R-30 or R-40 range if a professional took on the work.
The horizontal bottom chords of most garage trusses are designed to carry the weight of drywall and insulation. So if your ceiling is unfinished, you have some excess carrying capacity up there: 5 lbs. per sq. ft. is a safe estimate.