Mancave door - Soundproof?

[Mark_17]

A simple towel laid down to block the opening at the bottom of the door works wonders. Its a great quick, short term solution.

 

[Zeus36]

Ever watched James Bond enter or exit M's office?

 

[Zeke]

Since it's such a sticking point, I have a serious question: Do bedrooms in California not have return ducts? Do you have to leave your bedroom doors open all the time to get heated/cooled air there?

Most houses of modest size have one return air duct located centrally. If there is a hallway, it will likely be there. So each habitable room has a supply and there is no need to leave a door open if there is a path for return air to follow. A typical interior passage door is 30" and one inch at the bottom amounts to a scant 30 sq. in. So, if you have a typical 6 x 12 register, that is larger. There is math and dynamics here that can get complicated. I used to just compare the sq inches of each but that's not all there is to it.

The point is, most carpet installers don't know or care about return air. In my experience they care about whether a door drags on the carpet. If it doesn't, they rehang the door and job finished w/o any regard to air circulation. I've had many 'discussions' with homeowners when installing new interior doors. Many insist that the door be left just above the carpet for 'privacy'.

 

[racecougar]

Most houses of modest size have one return air duct located centrally. If there is a hallway, it will likely be there. So each habitable room has a supply and there is no need to leave a door open if there is a path for return air to follow. A typical interior passage door is 30" and one inch at the bottom amounts to a scant 30 sq. in. So, if you have a typical 6 x 12 register, that is larger. There is math and dynamics here that can get complicated. I used to just compare the sq inches of each but that's not all there is to it.

The point is, most carpet installers don't know or care about return air. In my experience they care about whether a door drags on the carpet. If it doesn't, they rehang the door and job finished w/o any regard to air circulation. I've had many 'discussions' with homeowners when installing new interior doors. Many insist that the door be left just above the carpet for 'privacy'.

Is that due to installation of central HVAC into older buildings over there, a holdover from old practices, or is it really the norm in CA?

I can't say I've ever seen central HVAC laid out with a single central return here in the Midwest, though I could see someone doing so if they were retrofitting an old building. Every room with a supply, other than bathrooms and utility rooms, has a return here. Provided that the OP's house is built in the same fashion, sealing the door shouldn't cause any notable HVAC issues.

 

[strutaeng]

Sound transmission is difficult. We've got an office/multitask room upstairs with a short hallway leading into a very large double volume grand room. All gypsum is 5/8" type X, walls and ceilings in this portion of the house. It was an addition. Floor on the second floor is 1 1/8 sturd-i-floor with hardi backer and ceramic tile. Fiberglass insulation in the floors and ceilings. The door to the office is 1 5/8 solid core door. Mass is your friend here. The bottom of the door does have a gap for central AC purposes.

Anyways my youngest is such a crybaby (no surprise, right!). If the kids are screaming or being loud I can definitely hear them into the office.

My advice is to get one of those office partitions with that material that helps with sound and put it in front of the door. Or get a cubicle. The company I used to work for moved office and they gave me like 4 of those partitions, but I donated them to our school. Or build yourself a little soundproof cube inside. Folks that do home music recording build them. Back during the covid lockdown I remember hearing stories about folks getting inside their closets because everyone in their households were in zoom simultaneously.

 

[Zeke]

Is that due to installation of central HVAC into older buildings over there, a holdover from old practices, or is it really the norm in CA?

I can't say I've ever seen central HVAC laid out with a single central return here in the Midwest, though I could see someone doing so if they were retrofitting an old building. Every room with a supply, other than bathrooms and utility rooms, has a return here. Provided that the OP's house is built in the same fashion, sealing the door shouldn't cause any notable HVAC issues.

Only offices here, and not all, seem to have supply and return in each separate room. General open areas might have multiple returns placed about the room. I know HVAC engineers spend more time WRT to commercial.

I haven't been involved with construction for some years now after 50 years of that type of work. New housing has always had the typical layout I described above for decades. Retrofits as well. Many larger houses have zones and indeed, separate systems. IDK about a new house today.

 

[Denwood]

A solid core interior door will help a lot. Insulating the wall with help too, but it sounds like there is very little shared wall.

You could do like they do in adjoining motel rooms with two doors in one frame.

The gap under the door will be an issue. Keep it at a minimum, weather strip will help , but often not practical with and interior door. You might need to add a threshold.

Solid core, seals, and if you can't use a threshold, then use one of these. We used them on our last commercial project:

High Quality Automatic Door Bottoms | Drop Down Acoustical Bottom Seals | TMhardware.com

Choose from the Largest Selection of High Quality Automatic Door Bottoms with options of Surface Mounted, Semi-Mortised and Mortised and different finishes and sizes.

www.tmhardware.com

You should be able to source them locally from a company specialising in commercial windows/doors etc. You can also beef up an existing door by fastening 1" or 3/4" MDF to it inside (and outside ideally too) with a layer of Green Glue in between.

@ukiltmybrutha , do you have any HRV or HVAC vents in your office? The door will be one issue to resolve, but if you google "flanking noise" you'll get some ideas on other paths for sound that may require some attention.

Is the house on a slab or floor over crawl space? Blown in cellulose is something you can DIY very easily and will make a big difference on any walls that need dampening.

 

[Alchase]

I had a similar issue with my home office. Mine is 10' x 10', with the door to the garage on one wall and a pocket door to the laundry room on another wall. And a window on another wall. It echoed something fierce, and noise from the kitchen on the other side of the laundry room would come through both doors. I added curtains to the window, and a padded fabric note holder to the back of the garage door. I close the laundry room door when I have Web Ex meetings. There is an air flow issue when the door is closed. It does not get as much heat or AC as it should. A small fan definitely helps and adds a little bit of white noise to block any sound comeing through the doors.

 

[racecougar]

I haven't been involved with construction for some years now after 50 years of that type of work. New housing has always had the typical layout I described above for decades. Retrofits as well. Many larger houses have zones and indeed, separate systems. IDK about a new house today.

Interesting that HVAC design varies that much from here to there. I guess we'll have to see what the OP's setup is (return vent in the room or not).