Like many voice actors with home studios, the issue of blocking outside noise can be a problem.  I recently visited a friends home who was building a semi-sound proof office in his home.  He had installed, sandwiched between the dry wall and standard 2x4 framing, sheets of sound board material he purchased at Home Depot.  This material is roughly 1/2 inch thick and does a nice job of sound proofing his home office from family noise in his home.

In my home voiceover studio I have a 4x4 window facing the neighborhood cul de sac and at time with kids playing and lawn mowers going, I just have to wait for a quieter time to do my voice work.  So I went to Home Depot and picked up a 4 x 8 sheet of sound board and cut it in half to fit in my 4 x 4 window.  I glued the two pieces together and added sound foam to one side and a handle.  This "plug" fits right in my window and does a very nice job blocking outside noise into my studio and it only cost me around $20 to make.

HERE'S A LINK TO A SHORT VIDEO I CREATED ON THE WINDOW PLUG 

We are planning to move and so this is a short term solution but works pretty well.  If you are looking for a more detailed look into ways to create a sound booth on a tight budget, visit my friend Paul Strikwerda's blog at http://www.nethervoice.com

Hope you find this information helpful.

Paul Hernandez, The Guy Next Door Voice
541-760-8035
paulvoices.com