Basement studio-room project in Boston area

[sharward]

I would think that the T & G floor above is tying those planks together really tightly as it is...

[Luftweg]

Here are a couple pics showing the 'grading' issues around the outside of the concrete walls...

There are several places where the ground actually slopes toward the walls, instead of the reverse...
I have not had the time yet to fix these...
Some of the places along the walls will also be fitted with drainage (especially if the wall is on a gable side of the house, or there is a 'compound angle' needed for the grade (i.e., the ground not only will slope away from the wall, but also will slope parallel to the wall)).

In the first pic, you can see where heavy rain from the roof (this is a gable side) pours right on the ground....
If the ground was sloped much more outward, and there were a gravel and pipe bed over thick plastic sheeting, just under the topsoil, this water would be drained away...
This is just outside of where the studio will be...

In the other pic, one of the downspouts enters a pipe in the ground and is carried away to a drywell about 20 feet away...
The other downspout was just recently added, and temporarily brings the water about 20 feet away via extensions....
(notice the galv steel ducting that was removed from the above floor joists over where the studio will be; these are being replaced with SuperDuct)
This is at the exact opposite end of house from where studio will be...


K

[knightfly]

Sooo, K, any questions you've asked that I missed, that you care about ?? I'm sorta trying to catch up; thanx... Steve

[Luftweg]

Sooo, K, any questions you've asked that I missed, that you care about ?? I'm sorta trying to catch up; thanx... Steve

Thanx Steve....

Well, the only real big one at the moment (until I draw up the design for the above floor's main duct soffit/chase) has to do with the spaces between the plank subfloor...

I have not had much luck with tests for filler material, so:

1.) All the materials I've tested cracked down the middle of the fill, or separated from the plank edges, or didn't fill the entire depth of the gap....
In lieu of having to use fiberglass tape on every space.... or otherwise mixing the filler with a reinforcement material, I'm lost.

I can see it happening that cracked, broken fills between the gaps might come back create noises in the floor when its walked over...

2.) What would be the effect(s) -- or rather isolation compromise(s) -- of leaving the spaces intact, and just adding the layers of sheetrock?

3.) Would: placing 8 foot long, single layer strips of plywood, say 1/4 to 3/8" thick, be a good addition that would allow 'tying' together of the planks? (the oak planks, the subfloor planks, and the plywood could all be screwed (and glued) tightly together).
This is for floor rigidity and noises, BUT would also allow a smooth flat surface for the sheetrock to attach closely too....
The subfloor planks are irregular enough that I think they might cause problems (cracking, snagging, breaking) for the sheetrock during deflections in the joists.

thanx,
K

[knightfly]

If everything you've tried cracks, it's probably because you filled the entire crack in one application; a lot of materials warn against filling deep cracks with a single application.

I'm also wondering if you've actually tested the REAL deal, or just the mock-up you mentioned? Specifically, are the cracks between your T&G flooring as deep as the ones in your test?

Also, even a cracked fill is better than an UN-filled crack (damn porn spam; now it's got ME doing it too ) because the smaller the crack/shallower the air gap, the higher frequency it's tuned to and the easier it will be compensated for by your beef-up.

If all else fails, I'd fill those cracks with acoustic caulk just before putting up your first layer - I'd make sure you don't fill too MUCH though; you want that first layer up tight against the floor. A slight under-fill would be better than too much. Any decrease in the depth of the cracks will be better than none.

Another reason for using acoustic caulk - even if it DOES crack, it shouldn't rattle or squeak. May not be the case with something that hardens... Steve

[Luftweg]

If everything you've tried cracks, it's probably because
you filled the entire crack in one application; a lot of
materials warn against filling deep cracks with a
single application.

Yes, you caught me. I did fill the gaps in one application,
and I'm sure this has something to do with the failure.
But, there are problems with only filling the gaps partially:
How can one get the stuff deep up into the gap, and have
it stay there (I've found that it often fell back down
towards the edges to varying degrees -- depending on
the filler)? It would almost have to be done with a bare
finger to push the stuff in deep.
The inverted vertical position doesn't allow to much for a
favorable filling.

I'm also wondering if you've actually tested the REAL deal,
or just the mock-up you mentioned? Specifically, are the
cracks between your T&G flooring as deep as the ones in
your test?

Although I haven't tried the actual gaps, I set up the tests
as real as I could: the wood was the same material and
thickness; the gaps were the same dimenions (width and
depth) as the real ones; I fastened the wood rigidly, so to
take out the factor of the wood moving during curing; the
tests were set up in the exact same position (inverted
vertical) as the real deal would be -- at the same temp,
humidity, etc. (basically I clamped the tightly assembled
test setups to the side of an actual joist above the studio).
The only real differences were that test setups were NOT
stressed with any joist deflections, as the real gaps would
be, and that there was wood at the depth of the gaps
(the real deal has kraft paper at depth of the gaps
(below the oak)).

Also, even a cracked fill is better than an UN-filled crack
(damn porn spam; now it's got ME doing it too )
because the smaller the crack/shallower the air gap,
the higher frequency it's tuned to and the easier it will
be compensated for by your beef-up.

I think I can understand that (that's the same issue we
were dealing with when discussing the ducts, no?).

If all else fails, I'd fill those cracks with acoustic caulk
just before putting up your first layer - I'd make sure
you don't fill too MUCH though; you want that first layer
up tight against the floor. A slight under-fill would be
better than too much. Any decrease in the depth of the
cracks will be better than none.

Acoustic caulk would be expensive, but I suppose
it could be done....
Should I use the backer rod, as Dan suggested?

Another reason for using acoustic caulk - even if it
DOES crack, it shouldn't rattle or squeak. May not
be the case with something that hardens... Steve

That's somewhat of a worry of mine.... would hate
to create any annoying noises....
What did you think of the idea of the 8 foot strips
of plywood (1/4 to 3/8 inch) to tightly tie the oak
floor and subfloor together, AND to allow that
smooth surface for the sheetrock (with less risk of
damage to the sheetrock by the floor planks)...

OR, are you saying that I should use the subfloor
as a lathe for filler, and completely cover them
(but they would surely crack/break with floor
deflection, no?)...

thanx,
K

[knightfly]

Now I'm getting confused; is this subfloor actually T&G, or is it just straight boards with cracks that go all the way to your finish flooring? (If it's T&G, you shouldn't be able to see your finish floor from below)

Either way, the more I think about it the more I'd stay away from any RIGID filler; wood expands and contracts with moisture content, etc, and that's the reason for NOT putting the subfloor in without spacing between boards. The only reason this isn't done for finish floor, is that it looks like crap and the finish floor will usually be in a more stable temperature/humidity, so wouldn't tend to be damaged by not leaving gaps for expansion... Steve

[Luftweg]

Sorry for any confusion...
It's a plank subfloor with spaces... the oak floor is, of course, tongue and groove.
I have attached a pic showing the planks and the joist sisters...
I know the gaps are directly shown, but if you look, you can see that they are 3/8 to 1/2 inch wide, and are naturally 3/4 inch deep...

Now I'm getting confused; is this subfloor actually T&G, or is it just straight boards with cracks that go all the way to your finish flooring? (If it's T&G, you shouldn't be able to see your finish floor from below)

Either way, the more I think about it the more I'd stay away from any RIGID filler; wood expands and contracts with moisture content, etc, and that's the reason for NOT putting the subfloor in without spacing between boards. The only reason this isn't done for finish floor, is that it looks like crap and the finish floor will usually be in a more stable temperature/humidity, so wouldn't tend to be damaged by not leaving gaps for expansion... Steve

[Luftweg]

I think I know what I'm going to plan for the plank spaces...

I will fill the spaces with the appropriate size backer rod so that the backer rod bulges out a tiny bit (some spaces are as tight as 1/4 inch, while others are up to 1/2 inch wide)...
(I don't think acoustic sealant is needed the whole length of the backer rods... just at the ends near the joists, maybe)
Over the planks and backer rod filled spaces (in the coffers, i.e., between joist spaces), I will place long strips of 1/2 inch or 3/8 inch plywood (8 foot lengths in the center of the joist spans, which will be screwed through the subfloor planks and into the oak flooring (but not nearly through! about 1/4 inch into the oak... all holes pre-drilled with appropriate bit size for screw/material)....

Then will come the blocking (might have to rip 3/8 to 1/2 inch from the edges of the blocking to account for the plywood thickness), at third or quarter spans..
(notchs in the blocking will also have to be accounted for, or else will be cut out after being placed.... this is to allow for the ceiling joists; thinking of gluing up two thickness, in order to provide strength around notchs)...

I will try to draw up something reflecting this...

Will be throwing the idea past the PE to see if it floats..

K

[Luftweg]

I just wanted to 'announce' that I'll be on a relative hiatus from any work on my project....

It's July now, and I have to immerse myself totally in preparations for my Board and licensure exams.....

Don't wanna risk failure -- it'd cost me another $900-1000 to take them over again!!!

Wish me luck?

thanx,
K

[AndreasB]

GOOD LUCK!!

[sharward]

Definitely! Good luck to you on that!

What board and licensure exams?

--Keith

[Luftweg]

Thanx Keith....

RPh for Mass...
I'm PharmD (technically, you can call me 'doctor'... lol)

K

Definitely! Good luck to you on that!

What board and licensure exams?

--Keith

[Luftweg]

GOOD LUCK!!

Thanx Andreas! I'll need it....

K

[sharward]

Fascinating! I had no idea...

So, you currently hold a PharmD ("Doctor of Pharmacy"), and you're studying for your RPh?

I just learned a bit about PharmD, but I can't find anything about RPh... What's the difference?

I want to see a picture in your thread of you with a screw gun in one hand, a hammer in the other, eye protection on your face, and a white lab coat on your upper body!

--Keith