A Possible Construction Project... Am I Nuts?

[AudiocRaver]

This is the house we are buying in North Carolina. There is room in the unfinished basement to make a pretty nice home theater / listening room, but I have been thinking about this possibility as well.

As the pics show, there is an addition off the back of the house. How horrible would it be to build a room under that addition, nestled between the pillars? The dimensions would be about 20 x 25 feet, not huge, but sufficient.

I had a nice diagram drawn using Stanley's room designer program, but they want to charge $3 per room to export a picture. Can't even capture a screen shot (grumble, grumble).

Thoughts / Questions:

• The screen / front of room would be where the ground has dropped off lower, away from the back wall of the house.
• The floor would be level with or only a little lower than the house basement floor level. There might be a single "split level" floor step down going from back to front of the listening room, moving away from the back of the house.
• Instead of pouring footings, could a bunch of stilts be driven into the ground (like your lake house, Sonnie)?
• By attaching to existing structure, the roof and one wall are taken care of. Downside is sound transmission into the existing house structure. It would also be nice to have the music room "float" to avoid sound transmission,
• The entrance would be from outside, no knocking holes in the existing house structure.
• Simple, straight walls, minimal complexity.
• No plumbing, only electrical.

Is it practical? Would it save money to build under existing structure, or make it more expensive? Obviously, I have not done anything like this before.

 

[Tony V.]

That's not a crazy idea at all. A 20x25 space is certainly usable but would mean if you want two rows you would be sitting a little close to the display. that or the back row would have to be close to the rear wall and they would have to deal.

I say go for it

 

[AudiocRaver]

Part of my simplistic thinking is that using existing structure makes it easier and less expensive to pull off. Basically, one wall and the ceiling/roof are done. Or kinda done.

But the reality might be that tying into existing structure is actually more complex and could end up costing more than a free-standing buildfing. I don't have the experience to know one way of the other.

Any insights from that perspective?

 

[Sonnie]

Is there anything beneath where the foundation would be... lines of any kind? The footers on that slope would have to be pretty deep... and can you get a concrete truck around there to make all that happen.

What's above that area?

I would actually build a 2x6 ceiling about 1 inch below the existing ceiling to decouple it. Same thing with the house wall... build it out 1 inch from the brick.

Both would be somewhat challenging because you need a backing on both. You'd have to frame the wall then stand it up. Framing the ceiling this way would be a challenge for sure, so it might not be as good of an idea as I am thinking. I would be curious how that floor is constructed and am I going to shake it down with my subs.

I am assuming there are no options inside that you can use? Why did you buy a house without a potential room ready to go?

 

[Tonto]

Those housed are extremely hard to find. That's why I recommended building. These projects pretty much always wind up costing more that building from scratch. But we gotta do what we can!

Agree with decoupling, I'd get a contractor/expert to advise you how to do it & turn him loose. I do like the slope...acts like a pre-fabbed riser!. A concrete pump should be all you need to get the concrete back there.

Post lots of pics!

 

[leecreek]

I would put it in the house if space was available. Big construction costs there under that floor. That hillside has to be dealt with.

 

[Todd Anderson]

I was thinking the same thing... the grading there looks like it could be problematic. But, these aren't construction eyes. ;-)

 

[AudiocRaver]

Yeah, footers would be ugly. And I agree that decoupling from existing structure would be preferable for the reasons you state - don't shake the house down and don't bother everyone else with my music and movies when the volume gets turned up and the subs get to shakin'. And how to accomplish the construction in practical terms - these were all questions.

I was exploring the option, but had already almost come to the conclusion that the practicalities made it a no-go. Your comments, backed with experience, are just what I was looking for.

The other option - quite a bit more practical - is in the unfinished basement, an area that I can make into a perfect one- to three- seat listening room / theater. I was hoping to come up with a space big enough for two rows of seats plus surrounds, but there is a load-bearing support pole to be dealt with, plus a water heater. The water heater can be moved. The support pole - we covered that in another thread. No moving the feller, it stays where it is The area is 22 x 12 plus where the 12 plus contains a support pole and a water heater right where a surround speaker would go.

The unfinished basement as is:

Option 1 - Basically a 1 person setup with a surround system..

Option 2 - 3 to 4 seats with a surround system.

I have no doubt I will be more than happy with the sound when I am done with treatments, etc. I was hoping for a bigger, more-ideal space, but I can make do with this and be very satisfied.

 

[Peter Loeser]

Very interesting construction. Making a room there is doable but as others have said, likely expensive. Looks like you'd have to relocate your electric meter. I assume that means you'd have to deal with buried cable at some point. I think you'd need much more vertical clearance to drive columns into the ground under there. A poured footing is probably doable. The flat work would be a good percentage of the cost I'd think, not sure if the accessibility issues would increase that too.

I say if you have the budget to make it work, it would be a great space. No chance you'd want to make an interior passage? I'd hate having to go outside and back in to get to my HT/listening room. Like Tonto suggested, you could have a civil engineer and/or contractor take a look and give you an idea of the scope of work required and maybe a ballpark cost. Might be worth a consulting fee to know what you're up against. Having the freedom to design the room from scratch would be excellent.

 

[leecreek]

Just my thoughts. If it was MY place, I would run a new (sized) beam over the first two post places to carry the load and lose them.. 24 x 22

 

[leecreek]

like this....

 

[AudiocRaver]

Thanks, leecreek, not out of the question. That would really open up the area. Just not sure how ugly the job of moving one or two support columns would get.

Peter, I'm afraid budget constraints become an issue rather quickly with the outside alternative. I could be a beautiful space, but don't know if it would ever get done if costs got out of hand.

 

[Peter Loeser]

What's your ceiling height in the unfinished basement space? Lee's beam suggestion could work nicely but may decrease your ceiling height quite a bit in that area. We did this in part of our basement to remove a column from the middle of what will be a family room. The steel beam is somewhere around a 11ft long and 1ft tall and cost around $800 I think. The job wouldn't be too ugly for a crew that has done it. If the space is unfinished there should be minimal surprises in terms of the existing structure. I'm not sure how much harder removing two columns is compared to removing just one.

edit: A steel beam certainly isn't the only option, depending on the construction of the house. Just one example.

 

[Sonnie]

I use and LVL above my room... about 20ft long... 4" x 12" and I believe it was around $200 back when I built the room. They also used the same beams outside on our carport when we built it after losing the garage. You can get them just about any length, and I know 24ft if available. Of course you have to be able to get it in the basement.

I like the beam idea best... and widen up the area some.

Does the fireplace stay?

 

[AudiocRaver]

Now we're cooking. Great ideas.

First the fireplace: It stays (not going to tear it out) but will not be used (there is a matching one in the living room upstairs and a gas one in the family room that its the extension on the rear of the house), and I have no problem in covering it non-destructively with treatment material or a second wall spaced in a couple of feet. Could make for a killer bass trap at the same time. The main body of the fireplace sticks out 1 ft 9 in, the base extends 3 ft 0 in into the room. Hmmmm, that is farther than I was thinking, that thing is eating up some serious real estate. Hmmmm.

MOVING THE BEAMS!!?!!&!!@!!

• Getting a beam into the basement is not an issue in this case, a double-door entry into the adjoining room from outside and a single door from there into the room shown in the diagram give a straight shot for hauling in a hefty beam. I assume on rolling cart(s)?? You will not drive it in on a flatbed with a crane, though.
• Height to the bottom of the main floor joists: 7 ft 4 in.
• Height to the bottom of the support beam (several wood beams now) that runs down the center of the house: 6 ft 4 in.
• Some duct work and plumbing will have to be moved, but that is small potatoes next to moving the support beams.

Instead of putting a new steel floor support beam UNDER the existing wood floor support beam that runs down the center of the house, how about adding two steel beams, one on either side of that wood floor support beam? Each would have a vertical steel beam holding up each end. Four new poles to replace the two removed.

I'm tired, I'll draw some diagrams tomorrow to show what I am thinking.

 

[leecreek]

You can "'nest" a beam in where the original construction was just laying the floor joists across the top of the current beam. Meaning if the floor joists are 2x12 laying across the existing beam, you can put temporary walls in, remove old beam, cut the ends of the joists off to fit the width of a new beam and anchor the floor joists with joist hangers to the new beam. All tucked up to the floor. The amount that it would hang down is dependent on the load requirements as engineered. A competent contractor would have no problem with this as it is getting more popular on renovating old homes for a modern open area.

 

[Tonto]

What size beam are you needing? I can cut up to 16.5 foot beams on my band sawmill. Don't know if a wooden beam will work, you could run it by your engineer. I'm happy to cut whatever you need. I can cut up to 26." Just come pick it up. We'll figure out some way to load it!

 

[AudiocRaver]

You can "'nest" a beam in where the original construction was just laying the floor joists across the top of the current beam. Meaning if the floor joists are 2x12 laying across the existing beam, you can put temporary walls in, remove old beam, cut the ends of the joists off to fit the width of a new beam and anchor the floor joists with joist hangers to the new beam. All tucked up to the floor. The amount that it would hang down is dependent on the load requirements as engineered. A competent contractor would have no problem with this as it is getting more popular on renovating old homes for a modern open area.

This sounds like a possible solution. It could yield a ceiling height of 7 ft 4 in, or thereabouts, with 2 old support beams eliminated.

I see you are in NC. Once I get out there we might have to get together some fine weekend.

 

[AudiocRaver]

leecreek: the more I think about it, the more I like it. It took me awhile to get it pictured in my mind, your last post did the trick. Thanks for the detailed explanation. The new place will be in Marion, a half hour east of Asheville, where one son and his family live. I will PM you when we get settled in.