Hi,
I'm just looking for some advice or opinions on a budget DIY sound proofing project I'm considering for my theatre room. Whether it is worthwhile or a complete waste of time.
I'm in Australia, the house is double brick with a tin roof and ceiling insulation (batts). The room itself has 2 fixed windows with 4 mm (0.15") glass 1200 x 500 mm (~47" x 20"). Double doors that open outside to a verandah that I never open 2300 x 1650 mm (90.5" x 65"), they are 6 mm (~1/4") glass I think with a small 4 mm pane at the very top. Internally there are no doors, so I need some double doors there too. That opening is about 2100 x 1500 mm (82.5" x 59").
The reason for sound proofing is to keep noise in and out. The noises I want to keep out are a neighbour's evaporative air con (can get a real whine to it at low to medium fan speeds), low to mid volume voices and low traffic noise. I'd like to deaden car doors and household doors being shut / slammed. I'd also like to watch my movies a little louder without disturbing my neighbours. Not at super loud volumes though.
What I am thinking of doing is packing ceiling insulation (batts) into the window sill for the 2 fixed windows (I have a good 130 mm or just over 5" gap) then covering with something like 3 mm or 6 mm MDF. I would do the same for the external doors (I think I've opened them once in 5 years so not fussed about boarding them up) and I would use some clear perspex at the top where there is a small fixed window, just so I can see outside and also for some natural light. I may double up with the thickness on this section though (it is about 200 mm (~8") high and the 1650 width of the door frame), I can't seem to find the right size sheets of perspex and what I have found is only 3 mm thick. I plan for the MDF to overlap the window sill / door frame and I will just fix it directly to the wall.
The double internal doors I will probably get quoted and professionally done as there is no frame there. I would not attempt that myself.
Some quick questions if you think this might be worthwhile, I assume I would need to fill the air space entirely between the glass and the MDF, so I would "double layer" the batts so they wouldn't be super tightly packed, but there would be no empty air space. Also, would it be worthwhile to buy some form of weather seal tape / foam and put that between the wall and MDF? I don't want to run any "no more gaps" type sealer between the wall and MDF. Just to make the removal job easier if I need to remove.
FYI, reasons for considering this way rather than getting it professionally done is money, money and money. Unfortunately double glazing, retro fit or new, is super expensive in Australia. Plus I may also consider moving in 4 to 5 years time and with our economy / housing market dip, it is quite possible any money spent on a company to do this for me, I would not get back. The room could also be put back to "normal" with minimal effort should I decide to sell. I also realize it would look fairly ordinary but I could hide it with cheap ready to hang standard size curtains. Also, once done, the room would be quite dark even during the day which doesn't really bother me.
Thanks in advance.