Finishing the basement

[Monk]

What kind of compressor do you guys have? My large oilless Husky died last fall, and I need to pick a new unit, but can't figure out what to go with.

Just had my wife dig out the paperwork to my latest compressor.
Its a Sears model No. 919.167620 Perm Lube Single Stage, Portable.
33 gallon tank - mine is verticle, but they sell (sold) the same model in a horizontal config.
150 PSI
SCFM @ 40 6.3
SCFM @ 90 4.9

I keep the working pressure not far below 90. Very nice recovery time and possibly overkill for your app. I have multiple lines attached and have used 3/8 & 1/2 inch air tools simultaneously (2 mechanics working) for extended periods of time - Not little nailer tools, mind you - talking about larger cfm mechanic tools. Will run continous - but keeps up.

For what I've thrown at it thus far, I've been pleased. This style compressor is a single piston design and I can see it wearing out in a few years if you gave it hard daily use in a real "shop" environment - I expect mine will last the full 10.

It was inexpensive + then a sale 2 weeks after my purchase brought the price down to 175.00 or so. Less thn a year old.

 

[beelzerob]

Real important point here is vapor barrier. Paint your concrete walls with products designed for that purpose. I don't know all of the details but you don't want mildew growing in your walls so ask someone whow knows all about that first.

If your basement is below grade insulation is important but not super important, I would look at furring strips with foam panels. If it is above grade and you get real cold in the winter, I would put up 2x4's and fill the space with fiberglass batts.

I guess that'd be like DL's sealing the concrete. Sooo...seal the concrete, THEN glue the panel insulation to the concrete, THEN build the 2X4 wall next to that?

The basement wall is *mostly* below grade. The grade slopes down along that back wall towards the walkout door.

I've heard of these "furring strips" on some google search of mounting the panels to the wall, but I couldn't make sense of it.

Who says you can't put a double door to the workshop? Poured cement cuts just fine with a gas powered saw with a masonry blade. Just header it off. You will love having double doors.

Hmmm...well I'll have to consider that. It would only be a convenience for the shop. It's too bad that area can't be a rec type area because I think then double doors would be a nice touch and a nice way to get natural light inside.

 

[apostolakisl]

furring strips are just 1 x 2 strips of wood. Put them up 16 on center then put your insulation in between them. The foam panels that are 3/4 inch thick are what you need. You can glue or nail gun the furring strips up and then glue the panels of foam. Then screw into the wood to hold your drywall or whatever your finished wall material is. You can put up 2 x 4s everywhere, its just that you make the room smaller and spend more money. Remember, the only reason you are putting any wood in the wall is to have something to hang the drywall on. It is not structural.

You will need to use special electrical boxes that are very shallow. Don't expect to be sloppy with your wiring in those boxes because it won't fit.

If you are using 2 x 4 s instead of furring strips you are doing it to get more space in the wall. The purpose would be for insulation and perhaps becuase you want deep electric boxes. No need to put up insulation first unless you really want a lot of insulation. Just build the 2 x 4 wall up against the cement and insulate between the 2 x 4's as you normally would. I think the loss of another 3/4 inch of room space, the effort of doing it, and the cost of doing it will likely not be offset by any measurable change in utility bills. If the wall is below grade you are only insulating against the Earth temp which will depend on where you live. I think you mentioned you are about 50 degrees in the geotherm thread. Insulating a 70 degree room against 50 degree Earth is only a 20 degree temp difference. And in the summer you want that wall cool.

As far as air compressors. I have a porter cable pancake deal. It is great. I can easily pick it up and take it whereever I am working. It runs nail guns, fills tires, air blasts things clean, and other random tasks. It does not have the capacity to run big air driven tools like grinders and stuff.

 

[KentDub]

Do a full wall with 2x4's for the theater. There is major acoustical benefit of adding more space for sound absorption. Make sure the insulation you get for the theater walls is acoustical insulation.

 

[beelzerob]

Good advice on the theater.

At this point, the only part of the floorplan pics I posted that we're actually going to do is the workshop area. I just wanted to map everything out that I could so that I hopefully won't have to uproot my workshop to make room for the other things we planned down the road.

Lou, I definitely want to be able to put shelves and other things on the walls...maybe something as big as a cabinet. I plan on putting up plywood instead of drywall to that end. I'd think furring strips will be too small for putting up shelves and such, so should I just plan on 2 X 4?

With electrical boxes, I don't mind if I have to mount them on the surface instead of in the walls. I know I'll need conduit from the ceiling down, but that's not a big deal to me. Adds character in a shop, I think!

 

[Photon]

Insulation and vapor barriers are non-trivial to say the least. Guess wrong and you have a mold factory. In researching how to insulate my basement, I found references to put the vapor barrier between the insulation and the drywall, between the insulation and the foundation wall, and in the case of the building code where I used to live, NO vapor barrier is allowed. The guidance that looks best to me is by Building Science Corporation.

Here is a link to one of their articles: Building Science Corp

Good luck. . . John

 

[apostolakisl]

No big woop on surface mounted electrical in the workshop, but I doubt you would want that in the bedroom and theater.

If you are going to mount heavy things on the wall you might just go with 2x4 everywhere. No need to do plywood as you can sink your screws into the studs directly. Plywood isn't the greates at holding screw threads anyway unless you put up thick (and expensive) stuff. 2x4's are pretty cheap, the more valuable loss is the 3 inches of room space. That does add up and when you figure the total cost per square foot of home, you will be surprised at how much money you have sitting in dead wall space.

As far as sound insulating your theater. That is very complicated stuff. Your biggest issue is with the ceiling above. If you put 2x4 walls in, do not attach them to the ceiling joists (upstairs floor joists). You should build the 2x4 walls up to a half inch short of the bottom of the upstairs floor joists. Then put another set of ceiling joists staggered in between the floor joists for upstairs, without having any contact to any part of the upstairs floor system. Use rockwool insulation above the ceiling and use a special sound deadening drywall. I have the brand at work and will post it if you want to know. Essentially, with a theater, you want to build a room inside a room, with no solid connections between the two. If you really want to get aggressive, put in a floating platform that rests on sound abosrbing pads and build your walls on that and then the ceiling on those walls. Basically, if you removed your house from above that room, you should be able to take a crane and remove the whole theater as an intact unit without cutting any screws/nails/glue/etc.

 

[beelzerob]

That was good info John...I spent a good portion of the night reading it.

The builder recommended 2 X 4 studded wall but held 2" away from the concrete....a scenario not shown in the bsc docs. Or he said you could do the foam board method, which DID seem to be recommended by bsc.

Interesting.

I appreciate the info Lou because I think it's making me realize once again that I don't want what I really thought I wanted. I think I'm leaning towards just a big rec room with a large screen to project movies and football games on. That's honestly probably the limit of my ambition....at least at this point. In 5 years.... who can say?

 

[pete_c]

I purchased a DeWalt to replace an oil type 30 gallon compressor a couple of years ago. I like it.

DeWalt

 

[Monk]

That was good info John...I spent a good portion of the night reading it.

The builder recommended 2 X 4 studded wall but held 2" away from the concrete....a scenario not shown in the bsc docs. Or he said you could do the foam board method, which DID seem to be recommended by bsc.

Interesting.

I appreciate the info Lou because I think it's making me realize once again that I don't want what I really thought I wanted. I think I'm leaning towards just a big rec room with a large screen to project movies and football games on. That's honestly probably the limit of my ambition....at least at this point. In 5 years.... who can say?

(From watching a million episodes of Holmes on Homes,) I think they want to avoid contact between the wood and concrete so the concrete's moisture will not weep into it causing mold

 

[apostolakisl]

That was good info John...I spent a good portion of the night reading it.

The builder recommended 2 X 4 studded wall but held 2" away from the concrete....a scenario not shown in the bsc docs. Or he said you could do the foam board method, which DID seem to be recommended by bsc.

Interesting.

I appreciate the info Lou because I think it's making me realize once again that I don't want what I really thought I wanted. I think I'm leaning towards just a big rec room with a large screen to project movies and football games on. That's honestly probably the limit of my ambition....at least at this point. In 5 years.... who can say?

(From watching a million episodes of Holmes on Homes,) I think they want to avoid contact between the wood and concrete so the concrete's moisture will not weep into it causing mold

2 inches seems like way overkill to me! Reminds me of the Saturday Night Live skit from like 20 years ago where they have a fake ad for a levatating cream you apply to public restroom toilet seats so as to stay far enough away that even the "heartiest of bacteria can't make that leap" (it levated you like 2 feet off the toilet). Between those 2 in, the 3.5 in stud, and the .5 inch sheet rock, you lose 6 inches of room.

If you look along the top of the foundation wall pretty much all homes have a vapor barrier and a pressure treated sill plate bolted on. No gap there.

It probably is worth considering what kind of moisture you actually have at your actual house. Some homes are constantly fighting the weeping wet walls despite sump pumps, french drains, and special treatments. Other homes never have a drop of moisture despite doing notta.

If you never have visible water weeping out of your walls, a simple moisture barrier applied as a sealer seems like it should do the trick. Hiring a local consultant who only makes recommendations and does not himself sell the stuff is most likely to tell you what you actually need.

 

[beelzerob]

Well, about a year ago I did discover some actual water sitting on the floor of a corner in the basement. I had no idea where it had come from, and it seemed a decent amount. I was looking overhead for water leaks from pipes, but none went there. Shortly thereafter we discovered mold on the nice pretty doors we had sitting down there, so we knew we had a problem. You could just feel the dampness of the air.

We had never been dehumidifying up to that point. We went out the next day and bought a pretty hefty unit, and it sits down there and keeps it at under I think 60%. We've no recurring issues since then.

The ground slopes away from the house well and we handle the roof drainage well, so I don't believe ground water getting in through the walls is a problem.

Ya, I was kinda skeptical of the 2X4 walls held away by a 2X6 top and bottom plate too, just because of all that room lost.

Still seems like the foam board is the best way to go then. I can either just put up foam over the entire area and then build my 2 X 4 wall up against that, or I guess use furring strips, which is what...just boards attached horizontally at 4' intervals?

I'll use pressure treated wood for anything sitting against the concrete. that's what we've already got in place for the wiring room and mechanical room walls.

 

[Neurorad]

I agree that taking some extra steps for sound insulation should be a strong consideration - loud movies, power tools.

The tricks that the HT experts use to diminish sound transfer into a HT are the same used to diminish sound transfer out of the room. As LouApo said, mechanical decoupling of a 'sub-ceiling' from the floor joists above may be a relatively easy (but difficult-sounding) process.

Sound isolation is a huge can of worms, though. You could 1) skip it, 2) put in a little $ and effort, or 3) spend a hundred thousand dollars on it. Pick your price point, and shoot for that. How much money is it worth to you to diminish sound transfer to the floor above - your call.

The AVS HT subforum is the best resource for 'soundproofing' info, some great links there.

I found some that may help -

http://www.soundproofing101.com/

http://www.soundproofingcompany.com/ (Ted White contributes a lot at remotecentral.com, very knowledgeable)

http://www.remotecentral.com/cgi-bin/mboar...hread.cgi?20966 (Ted White contributes)

 

[KentDub]

Sound isolation is a huge can of worms, though. You could 1) skip it, 2) put in a little $ and effort, or 3) spend a hundred thousand dollars on it. Pick your price point, and shoot for that. How much money is it worth to you to diminish sound transfer to the floor above - your call.

You're absolutly right, it is a huge can of worms. The rewards for it being done right can be huge.

I'd like to point out that sound proofing and acoustical treatment (though similar) are different. Sound proofing the goal is to prevent sound from entering/leaving the target room. Acoustical treatment is to improve the sound quality inside the target room. Sound proofing hurts acoustics inside the target room as likely will make more sound reflect back inside the room rather than bleed outside - to combat this you need 3x or 4x the acoustical treatment you would otherwise need (in fact, so much that you really can have no bare walls or ceilings). If the kids are moving out when you do this then I would opt for just acoustical treatment - if you only have two people in the house how important is isolation? only you can decide. FYI when I priced out my theater I came up with approx $10k for acoustical treatment and $40k for isolation. You can "build up" acoustical treatment over time, however, isolation must all be done upfront during construction. I agree, pick your price point and stick to it.

Kent

 

[apostolakisl]

foam board isn't a vapor barrier. Foam board is just for insulation. Decide just how much R value you want. Foam board, then 2x4, then insulation between the 2x4 is a fair amount of insulation. That is probably more than you have above grade or at most the same, unless you live way up north where 2x6 walls are used with an insulating board applied to the outside of that.

Consider this, at present you have zero insulation. Just how tough is to heat/cool the basement.

Furring strips are typically applied directly to a concrete wall in a verticle direction with the 2 (1.5) inch dimension flat to the wall, 16 on center. They are there pretending to be 2x4's for you to hang your drywall. Becuase the cement wall is structural, the furring strips are just screw acceptors. You would put your foam boards in between the furring strips for a total of roughly 3/4 inch of insulation.

If you do a vapor barrier it has to seal water from ever getting out of the poured cement walls at all. It has to be painted/sprayed on. If you put plastic, or some other product against the wall, water will weap out of the wall and be trapped between that substance and the wall and mildew will grow in there. If you choose not to seal the wall directly, then you shouldn't use any vapor barrier at all. In this way, any moisture on the wall surface will at least have the chance to escape via evaporation. Your dehumidifier keeping the air relatively dry facilitates evaporation. If your wall just barely lets moisture through, this may just work fine. Again, I suggest you have a pro make some measurements for you. Either you keep water out of the basement completely, or you allow it to evaporate.

Try this. Take a larege piece of clear plastic. Tape it up to the wall in several areas that you think are high risk areas. See if any condensation forms behind it. If not, you probably don't have much to deal with. If yes, imagine that condensation sitting there for years. It will start to grow mildew and stink or cause health issues. You may need to do this during all seasons, but I would assume summer would be highest risk.