Wall Insulation vs Attic Insulation | Foam Tech

Sep 14, 2020

Insulation for your property

We read about insulating our attics and water pipes all the time, especially right before winter. What about the walls though? Do you worry about your wall insulation, or do you even know if the walls have any insulation? If you’ve driven by houses being built, you see they add insulation before the exterior siding goes up and before the inside of the is completed. What about afterwards, though?

Which does the most good, wall insulation vs attic insulation, are both necessary? The average home should be insulated in the attic/roof, in the middle (walls), and low (basement/crawlspace). All three of these areas are important in the comfort of your home. We realize this can be expensive to do, but when insulation projects are done properly, they will provide an ROI over time. 

When you’re getting quotes to have your attic insulation updated, ask the cost of having wall insulation included. Many times, an insulation contractor will offer some discount when you have more of your house insulated. However, after getting the quote, you still feel like you can’t afford the initial cost, start from the top and work your way down. This time, the attic, next time, the walls, and last the basement/crawlspace. 

How do you insulate a wall?

Exterior wall insulation of an existing house can require removing the siding, or you can achieve exterior and interior wall insulation using blown-in insulation. Exterior wall insulation is a great defense against the loss of cool air in the summer and heat in the winter. Unfortunately, if your home was built prior to 1980, it probably doesn’t have any wall insulation unless a previous owner had it installed. The amount you’ll save energy expenses will well repay you for the cost of having wall insulation installed. 

Professional insulation installers will use special equipment that will cellulose or fiberglass fibers through a hose the contractor has stretched into your attic. If access to inside the walls isn’t possible through the attic, they will cut holes into the drywall inside your home and blow the insulation through them, then patch the hole up. 

Shredded cellulose and fiberglass blown-in insulation is shredded and will fit in the crannies, nooks, and the irregular areas around plumbing and wiring. This can be one of the best ways to insulate an existing home. 

If you’re wanting to do your own insulation, saving money on the labor a contractor would charge, you can find several videos online that will show you how to install wall insulation. Some big-box home improvement stores offer free classes on various home improvement projects, keep your eye on their calendar for insulation classes! 


What is the best insulation for walls?

R-value is the standard unit of measurement for the effectiveness for all types of wall insulation. The higher the R-value numbers, the better the insulation level against cold or heat. The R-value is determined by the density, thickness, and type of material of the insulation. 

For wall insulation in 2×4 walls, typically an older home, you should use R-13 or R-15 kraft-faced fiberglass insulation. This comes in rolls that fit between the studs of a 2×4 framed wall. For wall insulation in 2×6 walls, R-19 or R-21 kraft-faced fiberglass insulation is recommended, which comes in rolls too. This will fit the 2×6 walls to ensure insulation without leaving it too loose to be ineffective or too tight that the walls can’t breathe. 

What is the cheapest wall insulation?

For inexpensive insulation, fiberglass batts are recommended. This is still an effective insulation material, but it must be handled with care during installation because any tear will diminish the quality of the insulation.

Fiberglass batting insulation comes in packaged in rolls in a standard thickness between 16 inches, sometimes in 24 inches. It fits between joists and studs, popular for using in attics of new construction or anywhere there aren’t any obstructions. Fiberglass batt insulation costs up to $200 for a 500-square-foot area if you’re doing the insulation job yourself. If you hire a contractor, you can pay up to $300 for the labor in addition to the material. 

What are the wall insulation benefits?

You can expect the following from investing in wall insulation for you home: 

  • Reduce heat loss in winter
  • Reduce your carbon footprint
  • Reduce energy bills
  • Prevents mold

Is it OK to insulate interior walls?

Yes, in fact, many homeowners will do interior wall insulation for a sound barrier between rooms, even though it isn’t a total soundproof, it does reduce the sound significantly. Interior wall insulation can increase the privacy for bathrooms and home offices too. 

Is internal wall insulation worth it?

Exterior wall insulation is standard for residential construction, but not the interior walls. Many homeowners have found it to be worthwhile on a personal note for the following reasons: 

  • Sound Absorbency: Interior wall insulation can reduce the transmission of sound throughout the home. Sounds from running water, television, and washing machine are just a few sounds that homeowners are constantly trying to minimize. 
  • Cooling and Heating Efficiency: Cooling and heating is approximately half the energy cost of any home. With interior wall insulation, you lower the energy expenditure as it holds the heat inside each room during the winter and cool air in the summer. 
  • Control Moisture: When moisture is trapped within the walls, it begins to mildew the walls, mold grows, and everything begins to rot. With interior wall insulation, that moisture is controlled, minimizing this from happening. Whatever amount of insulation you can have installed, or do it yourself, will help your home’s comfort level and energy expenses. Yes, attic, basement, crawlspace, and wall insulation costs money, but the return of that money will be realized in your utility bills each month.

Call 855-794-3626 (FOAM) today for your insulation needs.


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