Exterior walls?

Hi all... Yes I did a pretty good search and I just got done reading Rod's book (great stuff by the way very helpful) but I have a few lingering questions. I will be building my room as a new addition to my house from the ground up. I have seen plenty of examples of interior walls and explanations of mass air mas etc but can someone post a sketchup drawing of a exterior wall section for me? I get to build it from scratch so I want to do it right, or at least as right as I can. I know brick is probably best but I am not sure that is in the budget (I am checking on that) so the next step is a wood wall. 1) How can you best and mass to a wood exterior wall? 2) How do you handle moisture? 3) I plan on having a lot of mass on the ceiling and then there will be a deck over top of it. What do I need to make my frame out of and how close together should I make the studs? Still standard 16 inch centers? I plan on going to an engineer with #3 here but I want to have a good idea heading into the project what it is going to take. Thanks for any and all help.

well you have to buld two buildings. The outer one should have one skin (i.e. outer layer) The ceiling should ideally span the whole building without the need of support poles, but we can get around them if it's too expensive to do it on one span. All moisture protection for that building is standard building code. you then build a second frame internally also with one skin - that's your two skin assembly. The internal frame should not be connected to the outer frame. Hope this helps cheers john

John Sayers wrote:

well you have to buld two buildings. The outer one should have one skin (i.e. outer layer) The ceiling should ideally span the whole building without the need of support poles, but we can get around them if it's too expensive to do it on one span. All moisture protection for that building is standard building code. you then build a second frame internally also with one skin - that's your two skin assembly. The internal frame should not be connected to the outer frame. Hope this helps cheers john

Thanks John. So are you saying that there is nothing different about the outer wall from any standard building then? I don't need to do anything special with this wall at all? I would think because I have the opportunity to build the way anyway that I want I should do something special with more mass? Thanks again. Mike

after sheathing the ouside of the structure you should cut strips of sheetrock the width inbetween the studs and place them between the studs against the sheathing to build up your mass ( known as beefing up ) on your outer layer ( atleast 2 layers of rock )

Also you should be looking into to your local building codes and get a building permit, which will require you to build the exterior walls a certain way. Commom things are #3 grade 2x4 on exterior walls and load bearing walls 16" on center, PT 2x4 against concrete, you'll have a minimum sheathing depth & type, you be required to provide "X" amount of insulation.... then you'll have to figure out with you code's requirment's and options you have for material, where to place that materail which will best sound isolate. Moisture> Vapor Barrier in the right spot for your climate. You very well may be required to hire an architect. Stamped plans will have all the requirements. Make sure to go through the reference section on this forum...Steve (Kightfly) has posted some real good stuff relevant to exterior walls. Although many users of this forum are very familiar with building and construction, most are adding to an existing structure. I too am putting up new exterior walls and the info I need for that is not really on this forum or in Rod's book... it's in my local building code and other web sites dedicateded more to building construction. In the end I'm using a combination of info for my exterior walls from here and other sources. BTW I would choose solid pour concrete over brick. Good Luck Marc

Thanks for the info guys. For the record…. I happen to work at an architectural firm…. :wink: I also have a meeting with the code inspector for our area on Web of next week and we will be going over all the code requirements for insulation and framing so I can get the permit going. I don't need a stamp but I am still going to run my design by one of the engineers that my firm works with just to make sure it is okay. I agree with Doni above, I was thinking of putting sheetrock between the studs on the outer wall but my fear there was moisture (that was exactly what I why I asked actually). I don't really know how to set up the vapor barrier for South West P.A. (Pittsburgh to be exact). We get pretty hot summers and pretty cold winters with a good amount of snow and rain fall all the time. Because walls in walls are not something that get done with any of the buildings my firm deals with no one around here really knows much about this. In fairness I have not asked around much about the vapor barrier yet but I wanted to see what folks around here thought about it. Concrete would be best but I have trees in my way and that means I need to use a post and pier foundation… that limits what I can build, it's either wood frame or brick. So what do you all have to say on the vapor barrier issue with new wall construction? Also is it a good idea to use sheetrock directly on the exterior sheathing?

For the record…. I happen to work at an architectural firm….

:lol: :lol: :lol: :oops: :roll:

guitardad72 wrote:

For the record…. I happen to work at an architectural firm….

:lol: :lol: :lol: :oops: :roll:

LOL I should add that I am NOT and architect (don't even play one on TV) but it is a nice resource to have, I am surrounded by 80 architects right now. I would point out that this building so unique they really can't help with allot of the questions I have been asking. For instance, like I asked above.... So what do you all have to say on the vapor barrier issue with new wall construction? Also is it a good idea to use sheetrock directly on the exterior sheathing?

That's like the old Spike Milligan joke: man- "is that the Oxford University tie you are wearing?" Milligan - "yes" man "oh really - what were you doing at Oxford" Milligan "Buying a tie" cheers john

John Sayers wrote:

That's like the old Spike Milligan joke: man- "is that the Oxford University tie you are wearing?" Milligan - "yes" man "oh really - what were you doing at Oxford" Milligan "Buying a tie" cheers john

Yuck yuck yuck.. everyone is a wiseguy.... :D So any comments on the idea to use sheetrock directly on the exterior sheathing there Robin Williams? LOL

I wouldn't use sheetrock (I assume you are refering to drywall) as an external sheath. There are much better products for that purpose that are waterproof and specifically designed for that. cheers john

John Sayers wrote:

I wouldn't use sheetrock (I assume you are refering to drywall) as an external sheath. There are much better products for that purpose that are waterproof and specifically designed for that. cheers john

LOL This is like a game of 20 questions.... Okay so what would you recommend then? I have only built standard wood frame walls before, nothing like this so any help would be great.

well there is Plywood and OSB plus the following alternatives. http://www.toolbase.org/tertiaryT.asp?T ... entID=3984 cheers john

i wasnt saying to put sheetrock on the exterior walla as sheathing i was saying cut strips of sheetrock against the sheathing on the inside of your exterior walls BETWEEN the studs