Door Construction

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The idea for the hollow door was something I remembered being mentioned on another studio forum, I've just had a dig around and found the post I was referring to:

http://www.johnlsayers.com/phpBB2/viewtopic.php?t=1662

In it, Steve (Knightfly) suggested the hollow idea but states in his diagram

"at bass frequencies the standard exterior solid-core door is 1-2db BETTER than the hollow sandwich type shown here. For most frequencies though the door shown here would sound noticably quieter"

So it's all down to whether you want good overall isolation, or bass specific.
Lets face it, the door will not be soundproof anyway, you're looking at damage limitation here. Would you rather the peeps outside heard the music your playing, albeit quiter, or just heard the hum from your low freq's?

To be honest though as there's only a few db's difference you'll probably do ok with either as long as you build it accurately, which is what really matters.

cheers :)

Ps. you stated
I used diligent innovative construction with Rod Gervais's help, and built my own ISO brackets to avoid contact of the new framing members with existing framing members

How exactly did you make those? I've found similar for sale over here in the UK and they cost £££ to buy, about $25 each in your money :eek: I too would like to build my own, maybe you can knock a few up for me ;)
 
Yes Sir Deluks

Ya know Deluks ....

I really like this site! ;)

Contributors like you and Rod, and Rick, and frederick, and Innovations, and so many others helping folks out ....

One just has to be patient - because sooner or later, after you've established yourself as an honest 'do-it-yourselfer' with credibility and reasonable intelligence, you're gonna get answers and plenty of em! :D

You just have to be patient, and not get offended, or frustrated too easily :rolleyes:

Yes, I see now (as you have pointed out), and as I really knew all along, that
"as long as you build it accurately, it's what really matters."

Yes Rick, and Rod, I will go for SOLID doors ;)

What I'll do now, is to look for some surplus, or used heavy solid core doors, and perhaps sandwich two of em together - yes?
There's plenty of such places like that here in Philly ;)

Maybe two doors each 1 1/2" totaling 3" thick? Or something like that?
(and I'll reinforce the jamb accordingly)

All I need to know now is any preferred method of attaching (sandwiching) the two of them together?

Construction Adhesive - with some mechanical fastening as well? Countersunk Flathead Wood Screws - or something like that?

I'll make it work man :D

Hey Rod - $900 bucks I don't got dude :eek: :D

But I do really appreciate everyone's help here! ;)

Now Deluks here's few photos of my home-made ISO brackets, (as per Rod's approval), and a few ISO hangers from Silent Source as well:
http://home.ucwphilly.rr.com/livesound/combo-gas-2.jpg < Once the room was a complete assembly (self-supporting), I removed some of these ...

ISO hangers from Silent Source:
http://home.ucwphilly.rr.com/livesound/ISO-Hangers.jpg
(these were GREAT!)

And here's a few progress shots from last summer:
http://home.ucwphilly.rr.com/livesound/progress-2.jpg < Outside View
http://home.ucwphilly.rr.com/livesound/progress-1.jpg < Inside View

It was the entire 'PROCESS' that I really enjoyed - What a Challenge! :D

Ok fer now ...

Sincerely
Mike
 
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What I'll do now, is to look for some surplus, or used heavy solid core doors,
NOW YOUR TALKING! I LIKE IT. Makes sense, but do yourself a favor Michael. Understand that MOST solid core doors are simply PARTICLE BOARD with a ply veneer, and hardwood edges. Look at the doors closely for any signs of the veneer layer loosening from weather or something. You might even find a REAL solid hardwood door too. They usually have a core of hardwood planks joined together and then a skin laminated to both faces .
You can always add a layer of CONCRETE BOARD, and a layer of veneer ply or MDF with a veneer over that too. The concrete board is heavier than MDF, only 1/4" and cheaper than lead. Just predrill and countersink holes to fasten it to the solid core door. Hey Michael, us DIY'ers gotta stick together and find ways to do this stuff CHEAP!!! :p Anyway, good luck no matter what you do, and post som pics when your doing it!
fitZ :)
 
Mike,

Understand something here - of that 900 bucks - the majority of it is the weatherstripping - - the door (bandy new at HD) is only 60 of that. The lead is another 140 and the pllywood another 60. SO 260 bucks for the door itself - all nice with plenty of mass.

The other 640 bucks you're gonna have to spend for hardware. Heavy duty hinges - drop seal - multiple door seals - pull handles - throw bolts - door closure. I don't have any idea how you get around all that. If it isn't air tight when you're done you might as well use hollow core doors for all of the sound isolation you'll get out of the assembly.

So it's 260 dollars new for just the door with a mass of roughly 15 psf - perhaps you can save a few bucks by picking up a used door.

Sincerely,

Rod
 
Hey Rod - Ok - We're narrowing down the plan!

Ok Rod, Fitz, frederic, Deluks, and others ;)

How's this sound:
Yes at least one solid-core 1 1/2" door, perhaps sandwiched by another, or at least veneered with 3/4" MDF (attached to each other with liquid nails, and counter-sunk flat heads)

The jamb will be reinforced with 5/4" Pine over the 2x4's all around the perimeter

Hinges will be at least #3 ball bearing type - heavy duty - mortised? yes?
(into the edge of the door, not the additional veneer edge)

ALL cracks and gaps associated with the jamb construction will be thoroughly caulked and sealed

Good solid threshold - something hefty

Lay the carpeting down first, followed by door construction

No penetrations for door knobs - door pulls only

Gotta find some nice strong magnetic latches

The door stop will also be homemade perhaps 3/4" or 1" wide covered with 3/8" neoprene, or facsimile where the face of the edge of the door meets the stop - yes? (don't forget boys I'm an innovator, a 'DIY' like Fitz said) :D

Do we tweaking?

Thanx guys ...
Mike
 
Yes at least one solid-core 1 1/2"
Just for information sake, usually solid core doors are 1 3/4"(so you don't build the jambs assuming stuff!).
As to the neoprene, I would find the 1/2" round SEALS instead Michael. In fact, the reason Rod said to offset the last sheet of ply, was to create a 90 degree path for leakage. Use weatherstripping AND seals maybe like this. Just an idea Michael. Out of time. Later.
fitZ
 

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Wow. I thought I stroked shit to death and worried about minutae.

Fuck, you guys are LIGHTYEARS beyond me! :D
 
Hey Fitz - still there buddy?

Hey Rick I scanned that last post of yours - very interesting post dude :cool:

Well Fitz, did ya see my clarification drawing?
http://home.ucwphilly.rr.com/livesound/dooroffset2.gif

Did you see where I may have misinterpreted the 'Magnetic Latching System' for a 'rubber weatherstrip' on the face of the stop?

Ya know I'd like to go with just 2 heavy duty slide bolts on the inside of the door (nice n tight) (I'm already way over budgeted) :eek:

Can you please check for any other misinterpretations on my part in regard to your CAD drawing?

I'm gonna go out today and shop for 'USED' solid core doors. I will be checking out the door's condition (as per your advice, and others)

Fitz and others - thanx so much!

Hope this post isn't getting 'too old'

I am definitely making progress thanx to you guys!

Best Regards
Michael Fraticelli
ROCKON@ucwphilly.rr.com
 
Well Fitz, did ya see my clarification drawing?
Yea, I sure did. Thats great. I would have done the same but I didn't have time. I'm on the last day of a building project myself, with a deadline. FUCK I hate deadlines. Of all things, it's a shelter for a WOLF :eek: ....hahahaha. I already built a smaller one for their Rocwieller. Geeeeezus, this thing is HUGE. Oh well, lifestyles of the rich keep people employed :rolleyes:
Well, about that drawing. You know Michael, I only try to draw ideas, NOT set them in stone. This coulld be interpreted different ways with different budgets, skills materials etc. It was only to illustrate a DOUBLE offset. After checking into designs from companys who build acoustical doors for HIGH isolation, I found that one of the biggest leaks is the path around the door. This is how THEY solve it. Double stops and seals. Which means the threshold too!! Otherwise the weak link syndrome rules. I didn't have time to detail that, but personally, I'd use a CUSTOM made solid hardwood threshold with TWO compression seals. I don't have time to draw it today, but tomorrow I will. ALSO, DON"T forget that for close tolerance doors, the LATCH EDGE MUST BE BEVELED.. 4 degrees usually works. This means the additional MDF panels will have to be beveled ALSO. Probably best to machine
the bevel on the panels PRIOR to fastening them to the door. Once the door is up, THEN size the thickness of the stops for close tolerance. I'll also draw a picture of that tomorrow. This bevel is VERY important for a tight gap. Also, the alignment and detailing of the stops/threshold seals is very important so you don't have gaps. I'll draw an alignment drawing too. But you have to let me know exactly what you are using for seals. No doubt there will be a NON flush threshold, but most front doors have some sort of threshold yo step over anyway. They do make a threshold that LIFTS the seal, and some that have a spring loaded aluminum extrusion/neoprean seal. These can be found at most hardware/home improvement stores. I even have one in the shop. I'll post a pic of it tomorrow.


Did you see where I may have misinterpreted the 'Magnetic Latching System' for a 'rubber weatherstrip' on the face of the stop?
I've read that the magnetic stuff isn't that good. Not only that, you have to ADD a metal strip to the door..otherwise what would it pull against. What I drew was a secondary FOAM or NEOPRENE WEATHERSTRIPPING seal. There are MANY ways to do this. I didn't have time to REALLY detail it the way I see it. That seal would be better as a HALF ROUND compression seal similar to what the other looks like. But, how much time and money do you have??? :D

Michael, one other thing. I would forget the SLIDE BOLTS. Saftey and possibly code would dictate the use of something else. I DO have a couple of ideas, but again, tomorrow.

Hope this post isn't getting 'too old'
The only thing thats getting TOO old is ME :D (no prob Michael). One other thing here. Rod is the expert, I'm just a detailer. He may think my ideas are redundant or something. If so, no big deal. I tend to overkill on details...that is what I did for a living for 15 years....hence...DETAILS!!! Later Michael. Back to the wolf house...damn, got to move it today..fucker must weigh a ton(I'll post a pic)
fitZ
 
Thanx again Rick - ok when ya get a chance

Rick ...

Take yer time - get those puppies in a good shelter first :eek:
(you're the man to do it!)

You mentioned:
"Double stops and seals. Which means the threshold too!!"

Yes understood - just one question though:
It's work - work ..... and although I said I'm game for it - just wondering:
I do have to build 'two' doors. As I mentioned, one at the bottom of my steps, and the other larger opening leading to the rear of the house (illustrated)

Smaller opening:
http://home.ucwphilly.rr.com/livesound/wide-view-1.jpg
Larger opening:
http://home.ucwphilly.rr.com/livesound/wide-view-2.jpg

Now, I just realized that the smaller door at the bottom of my steps, has LESS jamb width to do all those things like 'Double stops and seals'...

Believe me - all of this is what it is ....

Rick - If I have to build a door system there at that smaller opening with less construction glitz, than the other larger opening, perhaps I should just build both doors with a single stop as well?

Let me explain:
I'll stick to solid core doors (each opening), with additional MDF laminates.
Bevel the edges of the MDF exterior sheets. NO penetrations of door knobs.
Seal 'ALL' the jamb cracks and gaps. Stay away from magnetic latches. Install rounded door stop seals (open cell), on both door stops. I'll come up with a good closing concept - the rear exit door will be unhampered (slide bolts will meet code just fine). Mortised ball bearing hinges. And good tight thresholds (the bottom hallows filled) on both doors....

When ya get time - give this a thought fer me .....

Have a nice week end buddy ....

Best Regards
Michael Fraticelli
ROCKON@ucwphilly.rr.com
 
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The main concern with flush bolt hardware is that if, for example, you were in a medical emergency inside they would most likely have to demolish the door to get in.

Magnetic hardware comes in all sorts of sizes. remember that if you use spring hinges most of the work of keeping the door sealed against the rubber seals will be done by the hinges.

At the high end there are magnetic door locks capable of exerting many hundreds of pounds of force using electromagnets.

I have also at times speculated about adapting refridgerator seals to the task since they seem to have just about the right level of strength and certainly designed to be airtight. They do need a metal opposing surface though.
 
Innovations - How ya doin?

Nice hearing from you again - you were very helpful last year .... ;)

Yes so as you can see, I'm looking for some blessings here again.... :rolleyes:

I'm really trying to narrow this door construction down ....

''flush bolt hardware''
As I mentioned, I can deal with that - no problem - I'll come up with something that will work ....

My main concern, is the construction of these jambs, and the make up of these two doors. The CAD drawing that Rick drew up is terrific! But I realize now that I can't meet that specific criteria for both doors. The physical area of the smaller door opening just won't allow it: narrower jamb width, narrower door opening, narrower swing, etc. Perhaps I'll take another photo of the smaller door opening so you guys can see what I'm up against. But as I mentioned, I can't do anything about the tightness of that smaller door opening: http://home.ucwphilly.rr.com/livesound/wide-view-1.jpg

I guess all I'm asking for now, is a confirmation that as long as I can't duplicate that same heavier construction for two doors, does it really matter now?

Should I just go ahead and use good solid construction techniques for both doors (single stop systems etc - previously stated here), and consider it done? It would look something like this (I modified 'knightfly's' illustration - hope he doesn't mind) :D
http://home.ucwphilly.rr.com/livesound/door.jpg

Or should I still put the extra time and materials into that larger door (thicker door, double door stop etc.), and just deal with the limited jamb space in regard to that smaller door incorporating a single stop as best as I can?

Thanx - have a nice week end to everyone ....

Mike
 
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"I modified 'knightfly's' illustration - hope he doesn't mind" - not a problem Mike, go for it -

BTW, if you cut down pre-made exterior slab doors, I'd be really careful WHERE you cut - you want to keep solid hardwood for your drop-seal to fasten to, otherwise it may work loose if screwed into particle board - also, I recalculated and, for a REALLY thick door (like 3") going solid (2 layers 3/4 ply, 2 layers 3/4 MDF) the TL difference at low end is more like 4-5 dB, with the solid core winning. The same thickness door with 1-1/2" fiberglass center would run a bit better in mids/highs, but with a m-a-m resonance around 1200 hZ that drops the TL back down to 30 in that range. Generally, for music, solid wins whether you only can use ONE door or TWO.

Looks like you've been busy, glad to see you getting close; I've been too busy to make it around to all the boards I used to, launching a new "career" in Industrial Video among other things - later... Steve
 
Hey Steve - how ya doin?

Thanx for the reply - looks like I might be summing it all up soon :rolleyes:

Ok here we go :cool:

You stated:
"I'd be really careful WHERE you cut"
Understood :D

You stated:
"Generally, for music, solid wins"
Understood :D

Now just to clarify a few points on your original illustration, and considering all that I explained previously:

Please take a look here first:
http://home.ucwphilly.rr.com/livesound/borrowed-door-4.jpg

And now that a look here:
http://home.ucwphilly.rr.com/livesound/borrowed-door-3.jpg

Thanx
Best Regards
Michael Fraticelli
ROCKON@ucwphilly.rr.com
 
Michael, see if this is clearer - Steve
 

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Hello Steve

Well thanx for the additional sketches. :cool:

Unless I'm missing the concept here, it still appears to me that you're illustrating that the jamb will need to be rabitted the entire length of the jamb from top to bottom? The indentation in the door jamb seems to allow for a recess that creates a stop where the edge of the door seats itself. Then there is an additional stop.

Is this right?

Guess my more simplistic construction idea doesn't cut the mustard eh? :confused:

Sorry for the confusion :o
 
The main stop that actually stops the door is built into standard door jamb material; where you put the SECOND stop (and seal) is the only diff. If you're planning on building your own jamb from scratch, you have more time and patience than I do :=)) Steve

And yes, I'd use double seals no matter HOW you do it. Or just put a standard hollow core door in, don't fill the shim area, and live with STC 22, and a TL of about 10 dB @ 50 hZ...
 
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