Replies

1. 
   Woodbutcher | Mar 01, 2005 04:50am | #1

   What is the roof pitch?   (6-12....8-12   etc.) 

   What material are the rafters?    (2x6...2x8....2x10....etc.)

   How old is the house?

   Where are these "temporary braces"  located?   and what exactly are they comprised of?

1. 
   toddinmaine | Mar 02, 2005 06:25am | #2

   alright, I have pictures and measurements to go with my previous question... bear with me if I end up give too much info, but I was asked for different things from different people.... but, here goes.... <!----><!---->

   the original structure again is 25' X 34' (which is an inside measurement, wall to wall) ...the 25' obviously on the gable ends...  the rafters were rough cut 3" x 5", they are layed out between 33" and 36" OC... most closer to 33".... with the roof pitch being  11/12... the first floor ceilings were lowered at one point... with those joists now being rough cut 2" x 8"  layed out between 18" and 24" OC.... they are NOT one long board... they run the 25' span from each side to meet in the middle... these run this way on about 24' of the 34' with the other ones running from those to one of the gable end sides... also rough cut 2" x 8"....<!---->

   So, when I bought the house it had old shingles and a sagging roof... the rafter were visibly bowed.... they ripped about 4 layers of roofing off.... left with exposed boards... wasn't pretty.... they then proceeded to use these huge jacks poking thru the roof and raise each individual rafter to the same point along a straight line, then braced it in place. they did both sides, all 68' worth.... once all were relatively straight and braced, they resheathed the whole thing with 4 x 8 plywood... and put architectural shingles...  while the shingling was going on they were "marrying" a 2" x 12" x 8' rafter to the old ones and connecting the sides with a 2" x 8" creating my new second floor ceiling... which they concluded by strapping the whole ceiling....<!---->

   so, with this information, I will repeat the original question... I wanted to know if knee walls were "really" needed???  I would like to have as much space as possible... my speculation is that they ARE in fact needed... the roof sagged before, probably would happen again... but, not sure... I don't know if all the new framing would allow me to get away with no knee walls, or if that kind of span (34') should really be supported by a knee wall???  <!---->

   so, given my doubt, if they are needed, is there a minimum distance away from that outside wall that I should place the knee wall? to give it that required support... or is there a required headroom at the bottom of the slope near the top of the knee wall?<!---->

   added info... someone asked the "snow zone" of my location... only thing I could come up with referring to that is a "planting snow zone" of most likely "4", but possibly "5"... (map was not exact)    <!---->

   ALSO... had problems attaching the pictures I took... really bummed me out... wanted you all to see what I have....  even took a picture of my attempt at building the knee wall, just a short section... I was struggling over the angle and being sure the sheetrock would look right....  but, I've tried uploading for over an hour... will maybe try another time.... <!---->

   SO, I WILL FINALLY SHUT UP... any help would be greatly appreciated in this matter... sorry if I bored you with all my details... thought more would be better given I couldn't upload the pictures.... thanks again... I'll be looking forward to any of that expertise anyone would care to share, bye for now, Todd

    

1. 
   toddinmaine | Mar 02, 2005 06:31am | #3

   also, for more added info... probably useless information at that, but nonetheless, the space will be used for the first time.... completely open space 25' x 34'.... would like 3 bedrooms and a bath added up there... my family keeps growing...lol...  I am looking forward to good sized rooms... but, with the knee walls it makes them smaller than I had hoped...   with 2' knee wall space on either side... I would get bedrooms of 10 x 14, 11 x 14 and an 11 x 20... closets in 2 of them.. and a 6 x 10 bathroom.... this is the floor plan I came up with on graph paper... but... would like to turn that 11 x 20 master into 13 x 20 if I could eliminate the knee walls....

   the joists are supported downstairs with a bearing wall running that 24' I spoke of.... you mentioned they are overspanned... does that mean they need to be added to or shored up? god I hope not....

   you asked about the braces... they put those there after jacking the original rafters... came back around and added the 2 x 12's.... at the time I was thinking I wanted/needed the knee walls... BUT, in thinking, and getting space greedy... I guess I was questioning the need for them....  I haven't started anything up there, haven't touched the braces... contractor never took them down... figured he just left them knowing I wanted at the time to put the knee walls.... don't know if that really meant they were required..  I am just researching all the angles before I get going up there... don't want to take them down until I know for sure....

   as far as adding rafters... didn't think I need to do that... thought strapping the slope 16" OC like the ceiling, would be sufficient for the insulation and the sheetrock... you have me questioning that....  as long as there are collar ties above the ceiling, is there really a need to add rafters to the existing ones all the way to the ridge??? 

   so, thanks for the advice... hope you can help with my other questions?

1. 
   Gumshoe | Mar 02, 2005 07:39am | #4

   Todd - I haven't the wherewithal at the moment to read your explanatory posts. But I did get the gist - you think you might need knee walls in lieu of roof-purlin bracing, but you'd really like the extra space. Since knee walls are typically short walls below a low ceiling, might I suggest you add the walls, but include headers, then utilize the space behind the wall for cabinetry or shelving.

2. 
   CTDurham | Mar 02, 2005 08:11am | #5

   Todd,

   I can't speak for the building code in your area but, in North Carolina we have adopted the international building code 2002.  Code requires that the knee walls  be 5-feet AFF (above finished floor) regardless of pitch.  I guess this is like helmet laws, the law is trying to protect their citizens from bashing their brains out on a low ceiling.

   It sounds like the bracing currently acting as a knee wall is providing a load bearing function.  Code in our area states that load bearing walls from one floor to the next can be staggered or offset.  This offset distance can not exceed the depth of the floor joist below it.  So if you had a 2x10 floor joist, the load bearing wall sitting on top of it can not be offset more than 9.25 inches.

   One other code issue is meeting an R30 insulation value between the roof and livable space.  If you have 2x8 rafters you will have to fur them out to 2x10 rafters, install an air baffle and R30C insulation in the rafter cavity.  I think the the "C" in R30C stands for compact.

   Hope this helps and remember it is not the quantity of living space it is the quality that is important.  If the rug rats are not in your bedroom then that is what I call quality.

   Clark

    

1. 
   Piffin | Mar 04, 2005 04:36am | #14

   There are several ways to fit R-30 insulation into a 7" space, and since this is a remo situation, the requirement doesn't necessarily aply, tho it is nonetheless hightly important to him, whether he realizes it or not. 

    

   Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!

3. 
   CTDurham | Mar 02, 2005 08:39am | #6

   Todd,

   My mistake Code says 50% of the knee walls shall be at least 5' high but most of the builders in this area make all the knee walls 5' high for uniformity.

   On a side note the forum administrators do not want you posting the same questions in several different discussion topics.  (I guess it clutters up the site and does not benefit all the users because not all users will look at both discussion groups).  I have made the same mistake and try to post my question in the group where I think I will get the most bang for the buck.

   Clark  

4. 
   SantaCruzBluz | Mar 02, 2005 09:47am | #7

   Todd, when you build the walls for the bedrooms, will they not help support the roof?

   Allen in Santa Cruz

5. 
   buildem2 | Mar 02, 2005 11:49am | #8

   id be careful on wacking anything out of there before you can send pictures.(send the pictures in case it collapses then you can have before and after!)you sure these ''temporary braces'' arent collar ties? mabe im misunderstanding you.do they go to the celing joists? or attach to about every other rafter about 2/3 of the way up? hopefully the ceiling joists are connected well to the rafters good luck!

6. 
   DonK | Mar 02, 2005 05:00pm | #9

   Todd- You have good questions here, but in all honesty, this is not something to risk on a website with opinions from people who you don't know. You explained that your roof just had to be rebuilt. I wouldn't risk another problem. Call in a structural engineer or an architect, invest a couple bucks for a professional opinion and have it over with.  Then if there's a problem, you know who to blame. Besides, you will probably need something from a PE for the building department.

   Don

7. 
   rjw | Mar 02, 2005 06:18pm | #10

   Todd,

   Aside from code and structure issues, I've inspected a lot of "Cape" houses where the 2nd floor was finished with (i) no knee wall or (ii) very low knee walls way out towards the eaves.

   Once the height of the knee wall gets to less than about 4'-5' the space is usless and, in my opinion, makes the whole room feel awkward

   And, FWIW, as a home inspector, that situation also signals amateurish workmanship which heightens my degree of scrutiny.

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   Sojourners: Christians for Justice and Peace

1. 
   bladeburner | Mar 02, 2005 08:07pm | #11

   Knee walls <5 feet are impossible to sell as space and won't appraise here.

8. 
   booch | Mar 02, 2005 10:13pm | #12

   Tod,

   Wisconsin has a ruling that every room must have a minimum headroom of 7'6" for at least 50 % of the floorspace. No ruling on where the kneewalls go but here are a couple of rules of thumb.

   Grandfathered in walls allow you any headroom they made when constructed. Think before you tear out any walls. I have a long narrow granfathered wall that we use as a laundry room on the second floor. Man it is great. That's where the clothes are generated why not deal with it on the same floor.

   Supporting the roof with a kneewall...On what? Think like a post. If there is snow load or some load you are transferring down your kneewall to the lower floor you'll be cracking plaster & messing up the main floor ceiling. As designed, the rafters hold up the roof at the points they contact. I'd not count on transfering the load anywhere there isn't a direct path to the foundation. You can build the kneewall but don't "Jack the rafters to transfer the load to the wall. Keep that in mind before you think of cutting the collar ties, or altering the existing rafters. Triangles keep a roof supported.

   Second, what will you use the increased floor space for except to accumulate junk? As it gets lower & lower there isn't any way to walk back there and use it unless you crawl. A friend did a bungalow refurb and went to a 2' kneewall. All it accumulates is duffelbags, skiis, and stuff you don't use. Looks like hell and he had to carpet lots more area.

   Third think of what goes up there. A bed, a dresser, etc. I wouldn't make it any less than your bedroom dresser in height. Arranging furniture will be a problem.

   Finally the tax accessor works based on square foot of living space. I wouldn't build anything I can't use.

    

   Jack of all trades and master of none - you got a problem with that?
1. 
   toddinmaine | Mar 03, 2005 03:04pm | #13

   well, being an amatuer I guess I used the wrong term... I was figuring 2' from the outside wall as my "2' knee wall"... seems kinda foolish know that I think about it... it is close to 5' when  its 2' from the wall.... the rafters sit on a vertical wall that is about 42" high.... so,  I was thinking 2' of space....LOL.... well anyways... gonna go slap some sense into myself... oh, and BTW, I have the original contractor coming today... another on friday, and others are in the works....calling back.... so, I will have some other "local" professionals looking at it... I'll let ya all know what they said, you can tell me if their right.....  thanks again for the advice....

    

1. 
   Piffin | Mar 04, 2005 04:45am | #15

   Pictures are more needed than ever now. You started - I think - saying that you have a cape, but if the rrafters sit on a four foot high exterior wall, you have a vernacular farmhouse or a balloon framed greek style house.These lapses in language are forgiveable, but they point out the errant thinking in looking for advice via the web when you inadvertanatly provide inaccurate information which can only lead to inaccurate recommendations with potentially disastorous results. 

    

   Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!

1. 
   concretedetail | Mar 04, 2005 04:59am | #16

   Accurately put.

    

2. 
   toddinmaine | Mar 04, 2005 05:38pm | #17

   you know, I think I just said 1 1/2 story home, I don't know the style... tried to find out online... but, couldn't figure it out... all I know is that it was built in 1825 as a one room schoolhouse... my 80 something year old neighbor went here.....LOL....   the school closed in the early 50's and it became a home.....  I've been told its balloon construction... the ceiling used to go to the top of that 42" kneewall.... was lowered by someone with plans probably to put rooms up there... never happened and its now my plan to do just that....

   hard to really say what style of home it is, not that it really matters.... the house has had many changes to it over the years... someone actually hand dug the foundation under it.... picture a capital T.... bottom is 25 x 34 and top is 14 x 40(obviously an addition)....not to mention a covered screened in porch of 9 x 16...... it all now has concrete block or poured foundation..... flippen huge basement....... same measurements as above....except the porch of course...

   the house is pretty plain looking, it is vinyl sided... I had  a new roof done.... new windows.... previous owner only put shutters on one of the MANY windows.... 

   so, don't know what I'm trying to say, but, I was trying to get a little advice, you ALL have been great, I tried with no luck to post the pictures.... maybe my slow "country" connection..... not sure....  I didn't intentionally try to give inaccurate advice and have tried to update with all the stated questions...  I did post under "construction discussion" as well... (didn't know I wasn't suppose to do that for etiquette reasons) and "SAM T." made this incredible drawing that is a VERY accurate representation of what I have.....  if you care to check that  out... and pass on any further advice it will always be greatly appreciated.... so, I will try again to post the pics at later on today, "friday" but, for now, my daughter needs me... gonna run... take care all, Todd

    

1. 
   Piffin | Mar 04, 2005 11:11pm | #18

   Sorry, I didn't mean to i9mply that you would have intentionally provided wrong info, onluy pointing out that the confusion makes it hard to respond accurately. I had thought of doing a drawing like Sam did, but was getting too spread out mentally.Other forums are arranged in such a a way that you do need to ppost in more than one place to get all the attention needed. prospero's layout here keeps us all together a biot more and this is a very muych more active forum than most, as you have found out.now, on to posting attachemtns -
   When you make a reply, scroll down below the text window and hit the attach files button.
   The pop-up window( if you have a popup blocker, you might need to turn it off or adjust it) has a browse button. Hit that, and locate your digiphotos in your own PC. select one and hit open. Then the "upload" button
   Then comes the hard part - yopu have to wait until that file name appears in the popup window. once it does, you can then go select another photo to attach, and when you finiish, hit the "done" button, then hit the "post" message button in the first repy window. Your reply text will hover above the attachment as with these ones below.They are examples of a typical Greek revival home built commonly in Maine beginning in the late 1820s and thrities. Pubklic building s such as Schools and libraries were amoung the first to display this sort of architectural style. 

    

   Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!