Andy Eade's Rotten Basement Conversion Thread

unfortunately not - hence the reason for beefing up from below. I started replacing the screws with the 1/4 inch shorter ones and it seems to be fixing the problem. I suspect there is some inpenetrable layer between the subfloor and pergo (quickcrete maybe) that was being pushed up in places creating little bridges - and hence making the pergo springy in places. Hope to post some pictures tonight. Andy

WARNING! WARNING! WARNING! This thread slipped to page 3 due to inactivity! Earth to Andy! Come in, Andy! 8) --Keith :mrgreen:

Great thread Andy. It's been directly responsible for me taking a ton of things into consideration I'd never have thought of... Currently, I'm evaluating a drain system almost just like yours and I just re-read everyone's thoughts on building on top or beside the drain system. I'm very interested to see how that's going for you and what you've decided upon. I hope all's going well. Lee

Sandersd wrote:

3rd.......... building the wall assembly attached directly to the existing wall will increase flanking transmissions and decrease overall TL value of the wall assembly.

Irrelavent to outside if earth on the other side. Regarding transmission to framing above, life is all about choices: how bad do you want it and how much are you willing to invest to get it - cost/benefit ratio.

(... here I go again causing trouble...) Now, this discussion of whether flanking is 'significant enough' really interests me, since my basement studio/room project will have 2 of it's new walls bordering the existing concrete walls.... These concrete walls are 12-to-14-inch-thick poured concrete, with only earth on the outside of them for most of their height. I have been 'all set' to call the concrete wall the outer-leaf, and construct an inner-leaf of a stud/sheet-rock construction. But I keep wondering if I should just simply use the concrete wall mostly 'as is', since I feel it's so thick, I don't really see how it will create a 'significant' flanking path to the upstairs level -- and of course, I'm barely worried it could allow direct sound transmission through it (even if so, the nearest neighbor is 75-100 feet away). I also wonder if somehow by creating a stud-wall leaf inside the concrete, that I might actually creating a (minor) path from the middle air space between the concrete wall and stud-wall, to the middle air space between the above ceiling and floor and then through the floor.... By having just the concrete wall, the only potential flanking from sounding hitting that concrete wall will be through the huge, thick, dense concrete.... Isn't there a certain level of sheer mass in a single-leaf design that, once reached, might obviate realistic benefit from a double-leaf design? I realize that I may perhaps be misunderstanding something, or overlooking something. If so, PLEASE explain this to me.... Also, when explaining, please use terms of the exact comparison between the 2 scenarios I set up here, and not the same 'generic' mass-air-mass idea and examples that I already understand (fairly well anyway) that show lab-based transmission straight though a wall structure and don't account for the flanking. After all, we are told that having more mass in the pathway between sound and where we don't want it go, is better.... and really great amounts of mass are even better still.... At what point of added mass does a lack of air space become relatively 'insignificant'? (reworded:) At what point does an increase in mass of ONE leaf (of a two-leaf design) cause the air space to become relatively superfluous? ** Maybe the attached pics below will help explain what I mean: Scenario A: This is with just the MASSIVE concrete wall, and only an air space between the 2 ceiling leaves. Will significant flanking occur if concrete wall is VERY MASSIVE? If so, does it occur mostly at the top of the wall bordering the inner ceiling leaf? (and thus, would double-leafing a 'kitty corner' be an option for this? see Scenario C below.) Or does it start lower in the wall? Scenario B: This is with double-leaf on both wall and ceiling. Air space is more or less continuous from wall to above between ceiling leaves. Will significant flanking occur from air space between wall leaves up to air space between ceiling leaves (and thus through above floor)? Scenario C: This might be wishful thinking or dreaming. If flanking were to occur in Scenario A, could it be mitigated by 'kitty cornering' the inner ceiling leaf? thanx for any insight into this question bugging me..... K

Awesome -- can't wait to see the discussion!! 8)

well it's true that concrete is massive and has decent sound isolating properties in itself, they are not that great when compared to robust mass-air-mass construction. concrete will perform very well at low frequencies, but does less well once you get into the midrange. but by not doing mass air mass all the way around you are offering a direct flanking path up to your house for all the sound that does travel through concrete (particularly toward the top, where the distance to travel is smaller). if it were me i would do mass-air-mass on all sides and the top. PS ... granted Andy's thread has been inactive for a while, but it might be better to have this discussion in Lufteg's thread ... i kind of responded without thinking about that.

As Dan said, I'd be worried about the short distance between the studio ceiling and the floor above even with thick concrete. I wonder if you couldn't use those isolating bolts that are used to shock mount A/C compressors and just attach "studs" to the concrete wall with those. The idea would be to use the studs to hold up the inner ceiling joists but you'd have some isolation from the cement wall. You WOULD have little studs sticking out from your finished wall but a little decoration might solve that. len

Sorry about the lack of activity from me of late. April was kind of an expected month off from the project for me since my Mum and Dad were visiting for the UK for 2 weeks, followed closely by my Sister, Brother in Law and 21 month old Niece for another 2 weeks. As much as I love the studio and want it finished; as many of you with children here know - family comes first. I have been enjoying spending time with them, and have done practically nothing in the basement in the past 3 weeks. Of course once they leave next Monday I will be back into full swing again and will give you the latest updates; so stay tuned. I am of course very pleased to see that my thread is serving a purpose and was pleased to see my thread coming back from page 3 due to the recent dicsussions! :D Hope you are all well, and look forward to being back and fully engaged again next week. For now though I will get back to enjoying family time. Andy.

Awww, that's a cute lil' tyke!! :-) No problem, Andy -- take your time. I know I've been taking a bit of a vacation from my project, as the photos I posted from Hawai'i will surely attest! 8) 8) 8) I'm running out of excuses to get back to it though, so look for some updates from me as well in the coming days/weeks!! :twisted: --Keith :mrgreen:

len-morgan wrote:

As Dan said, I'd be worried about the short distance between the studio ceiling and the floor above even with thick concrete. I wonder if you couldn't use those isolating bolts that are used to shock mount A/C compressors and just attach "studs" to the concrete wall with those. The idea would be to use the studs to hold up the inner ceiling joists but you'd have some isolation from the cement wall. You WOULD have little studs sticking out from your finished wall but a little decoration might solve that. len

The diagrams above, as I posted, are more like 'theoretical' models... I'm not proposing supporting or directly connecting the inner-leaf ceiling to the top of the concrete wall..... What I was really trying to find out is if flanking DIRECTLY through some portion of the concrete wall up to the above floor (whether it started near the ceiling, near the floor, or anywhere between.... or all over), is worse than any flanking through a wall air space (if using 2-leaf design for the walls) then the ceiling air space, and then into the above floor (outer leaf)... Thus, assume that the inner ceiling is isolated from the concrete wall in all three of the diagrams, and then re-pose the question.... thanx, K

there is no way that sound traveling through the wall airspace is going to be worse than the sound that simply travels straight up through your ceiling airspace. i suppose there is more total energy in the airspace but most of it has to travel pretty far ... and the sound will have less power the farther it has to travel through air. and it's assumedly going to travel through a load of insulation i just dont' see "flanking" through the wall airspace being any kind of a factor. i see sound traveling through your naked, unprotected concrete wall being a factor though. because it will directly energize the structure above and it will radiate sound ... i'm no acoustician of course.

Dan Fitzpatrick wrote:

there is no way that sound traveling through the wall airspace is going to be worse than the sound that simply travels straight up through your ceiling airspace. i suppose there is more total energy in the airspace but most of it has to travel pretty far ... and the sound will have less power the farther it has to travel through air. and it's assumedly going to travel through a load of insulation i just dont' see "flanking" through the wall airspace being any kind of a factor. i see sound traveling through your naked, unprotected concrete wall being a factor though. because it will directly energize the structure above and it will radiate sound ... i'm no coustician of course.

Yeah, plans are now to put an inner-leaf inside the concrete.... I was just trying to incite discussion that isn't based mostly on those 'through the wall' diagrams that we always see (that pretty much don't seem to look into any flanking up to the limits of the test equipment) .... thanx, K

andy_eade wrote:

Hope you are all well, and look forward to being back and fully engaged again next week.

Alright, enough foolin' around! We want updates and we want 'em now! :twisted: --Keith :mrgreen:

Okay I'm back and have been working down in the basement quite a bit although there is no major progress since the beefing up process is taking so long. After two full days (with one helper) and about 4 evenings on my own, I have almost been able to complete the firstlayer of 5/8 beef-up with caulking too. It's definitely a slow process if you want to do t well I've found. Last night for example I was adding the backer rod and caulk and it was taking about 45 mins - 1 hour per joist bay (each bay is about 12 foot long). I have also found that the caulk occasionaly leaves little holes as it dries and I have to go back the next day and cover those. Anyone else experience this or have any idea if my caulking technique may be to blame? I have about 100 sq ft of the first layer left and then it's onto the green glue and second layer. I really can't wait to get this peice done so that I can start getting the walls framed. I want to see progress damn it! =) Hope you guys are all well, and sorry it's been so long!! I'm glad you guys didn't forget me and my little leaky basement!! Andy :D

hi Andy, yes sometimes i get littel holes too ... or cracks where the caulk didn't adhere properly to the side ... i think this has more to do with sloppy application on my part (not enough caulk maybe) than anything else ... i just go ahead and fix the few problem spots later. sorry to hear it is taking so long, i'm going to be doing a beef up sort of thing on my ceiling soon and i'm not looking forward to it (well i'm looking forward to havng it done, not the doing part).

andy_eade wrote:

I have also found that the caulk occasionaly leaves little holes as it dries and I have to go back the next day and cover those. Anyone else experience this or have any idea if my caulking technique may be to blame?

Oh yeah, I've got that too. I'm not too worried about it, though, since there's so little chance of there being a series of holes all lined up. (I have sooo many layers of beef, it's crazy! :lol:) Hang in there... Yes, it's tedious, but it's worth it. Would love to see pictures of the process. There's no shortage of people who haven't done beefing and there is a shortage of good photos on the process. 8)

I have about 100 sq ft of the first layer left and then it's onto the green glue and second layer.

Definitely take shots of the Green Glue process! 8) 8) --Keith :mrgreen:

OK - I'm back with pictures finally!!! Yes, the last month I have been hard at work every Saturday and weeknight with my room mate who has very graciously jumped in to save me on this project. I realized quite early on that beefing up the ceiling is most definitely a two man job!!!! SO without further adoo (sp?); here is the process I followed and pics from the ceiling beef-up. 1. Mudded all joints, cracks and knotholes in the sub floor. 2. Measured joist spacing (at both ends), and cut drywall leaving a ¼ inch gap around the perimeter. (drywall cutting tips below) 3. Attached drywall to sub floor temporarily with short drywall screws (check length against depth of drywall + sub floor). I used one every 12 – 14 inches, and only around the perimeter – none in the middle. 4. Filled the joints with acoustical caulk. 5. Installed Backer rod into the gap around the perimeter using Keiths hand dandy tool. It looks kinda like a pizza cutter, and is found in the hardware store where the window and insect screen bits are. This thing is the best $10 I ever spent! 6. Applied caulk around the perimeter. 7. Measured and cut the second layer of drywall. 7a. Test / Dryfit the freshly cut peice before applying the green glue. 8. Applied Green Glue to the next layer of drywall 9. Attached next layer of drywall using slightly longer drywall screws. (Check length against depth of 2 layers of drywall + sub floor). For this step I would have my room mate supporting the dryall peice with a 1x3 in each hand; applying pressure to the underneath of the drywall to ensure we get the screw into the subfloor. 10. Caulked the joints. 11. Installed Backer rod into the gap around the perimeter using Keiths hand dandy tool. 12. Applied caulk around the perimeter. 13. Finally, I attached 1x3x8’s to the joists up against the bottom of the drywall to hold it permanently in place. This is what I think Rod is calling “ledger” in his book. Again for this stage my roommate would apply pressure from underneath with 2 spare 1x3's to ensure we are fitting them real tight. And that was really it. The only other advice I can think of to offer for anyone who hasn't cut drywall before is the follwing process we found worked best / quickest. 1) After measuring your desired width, mark it at each end with a small score from the knife (regular stanley knife or drywall knife). 2) Line up the two marks with a chalk line and snap a chalk-line on the drywall. 3) Cut free hand down the line. 4) If drywall is in a stack, you can pull it until it overhangs the other peices and the score-line is just about where the edge of the peices below is, and then just lift and drop. The drywall will break exactly where you scored the line. Alternatively you can turn it over and punch it by the line of knee it. 5) Then while folding the broken peice back on itself to about a 60 degree angle, insert the knife and cut the paper. 6) Enjoy your freshly cut drywall. I also found it's worth having a surform (Drywall shaver), and a reciprocating saw for bits that need some custom shaping on site. I also have one random question for you guys and then I will post the pics. Do you think I should go with steel or wood framing. Here is the situation and reason for the question. I had the sump-pump system installed as you may remember (which incidently has yet to be needed), but still have a very humid basement - 65% RH appears to be the norm. The drywall contractor who will be doing the next stage (once I am done with the ceiling beef-up) only know's how to frame using steel, so I will need to find a carpenter or DIY the framing if wood is the way to go. I guess I;m really wondering about the humidity and whether steel might be risky given this high humidity level. What do you think guys? Okay, so now here for some pics. Hope u are all well, and God bless and protect Rod in his recovery! Our thoughts and prayers are with you brother! Andy. p.s. Pictures are actually in reverse order, but should show something like this: 1 - Pre drywall- all cracks and seams mudded in the subfloor. 2 - 1st layer of rock goes in 3 - Roomie installing the backer-rod with the handy-dandy tool. 4 - Applying the Green Glue 5 - Finished bays with 1x3 ledger installed (a.k.a. Cleats)

Awesome job! :D Great pictures -- thanks for sharing! Is that you in the photo, or your roomie? BTW, it's Dan Fitzpatrick's awesome tool, not mine. 8) I'm leaning towards recommending wood framing in your situation, given your high humidity levels. Wood can absorb and tolerate moist air much more than steel. You don't want condensation on your studs because it will promote mold growth. --Keith :mrgreen:

Hey Keith! Yeah wood is kind of the direction I was leaning in. Oh, and that is Dale my roomie. I need to start marking out on the floor where the wallks will go and test the room dimensions for nodes and modes I'm thinking... All that is left for the beef up now is about 3 joist bays that we skipped due to ductwork. I wanted to leave dropping that out until last since that will essentially knock out some A/C to the first level of the house for a few weeks. Given our 90 degree weather here in DC at the mo I'm glad I did!!! :D

I don't blame you for waiting. I feel your pain! At least ours is a "dry heat." I think I would just about die in that DC-area humidity you guys have. Guys, don't expect too much progress on my build this weekend. I just can't handle this kind of heat.

sharward wrote:

Awesome job! :D Great pictures -- thanks for sharing! Is that you in the photo, or your roomie? BTW, it's Dan Fitzpatrick's awesome tool, not mine. 8) I'm leaning towards recommending wood framing in your situation, given your high humidity levels. Wood can absorb and tolerate moist air much more than steel. You don't want condensation on your studs because it will promote mold growth. --Keith :mrgreen:

The work's looking good..... I too am seriously considering MOSTLY wood framing in the basement (except for the ceiling joists and lintels -- which will be steel due to height versus weight capacity considerations (I can use a shallower depth member in steel than I would be able to with wood); the metal used would be high-up from the floor, and never will touch any concrete or 'cold' surface). Alot of this thinking of using wood comes from that ASHRAE article that Steve had linked me to (and to many others no doubt), concerning hygric buffer capacity... Although I believe it is the appropriate thing to do -- to use wood that is -- I'm still wondering a bit about the significance of the hygric buffer of wood in a basement made with concrete walls... To quote excerpts from the article: "... The average home .... of wood.... yields a hygric buffer capacity of approximately 45 to 50 gallons .... Most water leaks are not a problem because of this large capacity to store water." Then, on steel: "... average home with steel studs and gypsum sheathing yields a hygric buffer capacity of 5 gallons ...In this type of assembly, even the smallest leak can lead to problems." Then, on masonry: ".... a similar sized home built with masonry exterior walls and masonry cladding... yields a hygric buffer capacity of approximately 500 gallons..." If the hygric buffer capacity of the concrete in the basement is part of the consideration, then it could seem to be quite significant, or even the dominant capacity (?); i.e., the comparative contribution from using wood framing versus steel framing IF the concrete supplies so much of a hygric buffer, might be much less significant than it sounds at first.... It would be nice if the article clearly made that comparison. Now, I don't think the article is specifically talking about basements, especially when it refers to 'wood' houses..... so that is a big question -- I wonder what would be the story if only basements are considered? Yet, if the air of the basement is humid, and the basement can get cold, steel, being the great conductor of heat that it is, could get 'cold' enough so that moisture in the air condenses on it (?)... If the steel gets cold enough, it could even condense moisture in air that might not even be considered that humid (that is, the amount of water in the air at the higher temp, re. relative humidity) This is where I could imagine the hygic buffer capacity becoming (more) of an issue.... in combination to the conductivity of steel versus the relative insulative nature of wood... There may be other factors as well to consider when choosing wood versus steel; the jury is still a bit out on this with my choice, but I'm leaning toward the wood.... NOW, IF wood is chosen, certainly the baseplates should be PT, but what about using PT for the entire framing? Then again, I really like the Hem-fir stuff -- it's always so much straighter and better looking than the SPF (spruce-pine-fir, UNTREATED of course) that I see... (doesn't seem to be much doug-fir here in the northeast, so I can't comment on it). PT is always seeming to be SYP (southern yellow pine), and I've heard that that stuff tends to warp and twist (and of course, it's harder to work, cut and drill) -- yet it's STRONG, and alot of the pieces I have seen seem to all be marked as #1 grade... it's not forbidingly expensive either. Any ideas on wood species?.... thanx, K

Hygric buffer capacity isn't the ONLY reason for wood framing; even with all that concrete, if your RH will be above 50% (40-42 is ideal) then steel will tend to have more problems due to corrosion as well. (Once your basement is "studio-ized", it should be easier to dehumidify, so hopefully you can get that figure lower) - If you MUST use steel in a higher humidity environment, the least I'd recommend is to get some cans of Zinc Chromate primer, and paint at least the cut edges with it (letting it dry, of course) before putting up panels or insulation. Southern yellow pine is supposed to be very strong, so should be a good choice (haven't used it) and PT for EVERYTHING wouldn't be a bad idea from a moisture standpoint; however, from what I've read most PT stuff isn't as structurally strong because they tend to use cheaper wood (like hemlock) because of better penetration of the chemical. I'd ask more about this at the lumber yard (NOT the "home center", they're usually too busy trying to remember to ask you if you want FRIES with that :roll: ) Also, ask specifically WHAT method of PT they use, meaning which chemicals; supposedly some newer methods are NOT carcinogenic, while others aren't allowed by some local codes for interior construction BECAUSE of their known/suspected carcinogenic properties... Steve

I can agree with the assorted values of using wood versus steel.... It may be a particular thing to the Northeast here, but I have not seen any PT at a lumber yard that wasn't SYP (but then of course I haven't looked everywhere and I have limited travels to such places... I'm sure some other species could be around, but I just have not seen it yet).... But I will start to pay more attention to see if there are other species that I just have not noticed (will study the stamps). SYP is not incised for PT, so there is no reduction in structural properties from that. I don't think CCA-treated PT is even readily available anymore, and it seems ACQ or borate can be used indoors without any restrictions, as long as the moisture is 18 percent or less before everything is 'closed-up'... (CCA IS available, but only for industrial purposes). It seems that most, if not all, light-guage steel framing is galvanized (and I have even seen it stored outdoors in the elements (heavy rain) at lumber yards, presumably awaiting pickup, without any rust on it). As for treatment with a zinc paint, I have only so far seen that welds should be treated, but nothing has been said about cuts or drill holes. Of course, galvanized steel could eventually rust (since it does have iron in it), and if it were in a constant moist environment I could imagine it might be bad... I DO know that I have used galvanized thinwall conduit for electrical in part of the basement, mounted directly on the concrete walls (and this part of the basement IS a humid place), and it has never developed any rust at all (although it isn't that near the floor, like steel stud baseplates might be... I couldn't really see vertical steel studs easily corroding if they are the same material as the conduit). Wood has alot of things going for it versus steel, especially when considering PT; it's cheaper, you can nail almost anywhere to it, it's 'warmer', the hygric capacity, etc.. The only really great things I like about steel still, is that it is always the same dimension (doesn't warp, expand, etc.), and it can be very strong (much stronger than wood) if the right guage is chosen. All in all, I think I will go with wood... (although I haven't even bought the full framing yet, and WILL be using SOME steel (in the lintels and ceiling joists))... But I'm still learning alot about this stuff, and have quite a way to go, so who knows? K

All good points; I'm being perhaps a bit over-cautious with the primer, but when things will be so tight I'd rather be over than under. A LOOOONG time ago I had some experience with galvanized steel siding (Seattle area), and (supposedly) the "guillotine" we used for cutting the stuff to length was also "smearing" the zinc across the cut, so no further treatment was necessary; we STILL sprayed the ends, it just made everyone feel better... Steve

Andy, please confirm your whereabouts and status before I submit your avatar to the milk carton manufacturers! Your thread slipped to page 3 of the forum, which is not good! I hope all's OK in your world... --Keith :mrgreen: