I had a few ideas in mind to keep our newborn from waking up our light sleeping toddler sleeping in the adjacent room. I'm open to new suggestions. :-)

1) Blow cellulose from above (unfinished area). I don't know if there is a firewall in the interior wall though so can't tell if the blown in will be blocked by it

2) Rigid foam boards, R-5 stuff available in my hardware store in the newborn's room, painted in something matching the room.

3) Egg crate foam stuck to the wall (seems very unattractive)

  • 3
    You may want to consider instead the use of a background sound device in the older child's room.
    – Michael Karas
    Mar 26, 2016 at 11:43
  • Slow expanding foam insulation would also work.
    – vini_i
    Mar 26, 2016 at 12:28
  • Options 2 and 3 are terrible fire hazards. Foam must be covered with drywall
    – user51917
    Mar 26, 2016 at 23:15
  • 1
    If you have a newborn, you really don't want to be starting any serious construction projects, which is what the best way to do this is: serious. 2 and 3 are out of the question, 1 might require coring holes, plastering and painting. Your solution is a noise machine. I haven't worked in many houses where I see toys but no sound maker; everyone seems to use them. Parenting.SE would probably provide you with some more workarounds, too.
    – Mazura
    Mar 26, 2016 at 23:44

4 Answers 4


The easy and fairly attractive solution is to use sound attenuation panels. You'll often see these in home theater settings. Hang them on the walls like you would a picture. You can DIY a similar solution by hanging a large thick tapestry on the wall, with an optional thin piece of foam behind it.

If you haven't already done it, carpeting in the room will make a huge difference.

To completely sound proof the room, you'd see the best results by removing the drywall from at least one side of each wall, and the ceiling if there's living space above, and installing specialized quiet drywall on top of sound attenuation channel that's attached to the studs like furring strips. This both separates the drywall from the studs to remove base sounds, and the quiet drywall absorbs the higher pitched sounds. However, even after all this work, there are still air ducts and doors that will often transmit sounds.


None of those will work well enough for the effort. 3) is a joke from the Hee Haw TV series. 2) won't work at all.

1) will have minimal effect but sound is transmitted by vibration carried through the floor, ceiling, and studs.

If you want to do it right, increase the width of the walls by two inches, alternating the studs ....

Yeah. Right.

Regards, A former radio and TV broadcast engineer


The cellulose would be best. But, if the topical application turns out to be the only option. Then, you'll need an absorbing layer between the foam board or the foam won't do much. The below Radiant Barrier (left - 4'x24' $60) is at the Home Improvement stores, the foil face would be taped to the back of the foam board to then sparingly screw that assembly to the wall(s).

Or, you can skip the foam & tape 2-layers of the radiant barrier back-to-back. One other big noise area is the room's door. You'll want to weather-strip (right) that before doing anything else. You may find that this is the real noise leaker.



I took an old iPod mini and added an ocean surf soundtrack to it that plays on a loop.

I then added that to an iHome amplifier base and now have the best sleep machine I have ever owned.

Cheapest first alternative.

Good luck!

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.