Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Roofing/Siding

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 05-17-2012, 09:42 AM   #1
Newbie
 
Join Date: May 2012
Posts: 8
Rewards Points: 10
Default

extend roof over flat roof


Hi, i am trying to find out if it is possible to extend a roof pane over my flat roof. i would like to do away with flat roof. im thinking of taking 1x 10 and spanning them from the exsisting roof ridge down to where the edge of the flat roof is. i am planing on building up the inner wall where the eave is now to support the new roof plus install a knee wall inbetween the exaisting flat roof and where the new roof will be to give it support. i drew out a pic that kinda shows what i wanna do. the thicker lines are the exsisting framing and the thinner line is what the new roof will look like. also i included the two wall sections i plan to add for support.


Last edited by nate1582; 05-21-2012 at 04:50 PM.
nate1582 is offline   Reply With Quote
Old 05-17-2012, 11:58 AM   #2
Doing This Way Too Long
 
Join Date: Jun 2008
Location: North Idaho
Posts: 1,160
Rewards Points: 524
Default

extend roof over flat roof


no pics but for starters I hope you meant 2x10 and not 1x10

OldNBroken is online now   Reply With Quote
Old 05-17-2012, 12:32 PM   #3
Newbie
 
Join Date: May 2012
Posts: 8
Rewards Points: 10
Default

extend roof over flat roof


yes sorry i meant 2x10s. picture will not upload. do u happen to have personal email that i could send the pic to.
nate1582 is offline   Reply With Quote
Old 05-17-2012, 12:36 PM   #4
Remodeling Contractor
 
Join Date: Dec 2008
Location: Sandy Hook, CT
Posts: 3,590
Rewards Points: 2,000
Default

extend roof over flat roof


yes this would work fine.
Bob Mariani is offline   Reply With Quote
Old 05-17-2012, 12:55 PM   #5
Newbie
 
Join Date: May 2012
Posts: 8
Rewards Points: 10
Default

extend roof over flat roof


Should i leave original rafters in place and just add the new ones. if you would like i can email you thie pic and it will show you what exactly im gonna do
nate1582 is offline   Reply With Quote
Old 05-17-2012, 12:58 PM   #6
Remodeling Contractor
 
Join Date: Dec 2008
Location: Sandy Hook, CT
Posts: 3,590
Rewards Points: 2,000
Default

extend roof over flat roof


I would leave them and then fill the void with blown cellulose. If you want a cathedral ceiling use 2X12 to allow enough space for adequate insulation.
Bob Mariani is offline   Reply With Quote
Old 05-17-2012, 01:01 PM   #7
Newbie
 
Join Date: May 2012
Posts: 8
Rewards Points: 10
Default

extend roof over flat roof


I was able to final download pic
nate1582 is offline   Reply With Quote
Old 05-17-2012, 01:48 PM   #8
Doing This Way Too Long
 
Join Date: Jun 2008
Location: North Idaho
Posts: 1,160
Rewards Points: 524
Default

extend roof over flat roof


Oh, you are just doing it on one side. Well, that brings up another issue. The internet is not really the place you want to get final approval on that. Yes, it can be done and your idea is sound. Aside from the issues of tying into what I am assuming is going to be the wall on the far side as well as planning raising any penetrations or chimneys to the new proper height you have a more serious issue to verify. You are now creating an asymmetrical roof design that will throw all your load bearing calculations out the window. You may want to check with a structural engineer before proceeding. With that new roof deck the lateral forces are going to be tending to push that structure forward to the left of your drawing with any weight on it. I'm not saying it's going to do it but theoretically it will. Gravity getting in the way of a good plan again. Stupid gravity.
OldNBroken is online now   Reply With Quote
Old 05-17-2012, 02:14 PM   #9
Newbie
 
Join Date: May 2012
Posts: 8
Rewards Points: 10
Default

extend roof over flat roof


I had the same idea on what would happen. my concern was that it would push the roof to the left cuz of the new weight and the fact that we get alot of snow in our area dosent help. my uncle is telling me that it wont. the ridge to eave pane is now 12 ft and he wants to extend it to 36 feet to cover flat roof. the pic issnt to scale either.the slope isnt that dramatic
nate1582 is offline   Reply With Quote
Old 05-17-2012, 02:47 PM   #10
Doing This Way Too Long
 
Join Date: Jun 2008
Location: North Idaho
Posts: 1,160
Rewards Points: 524
Default

extend roof over flat roof


Not saying it definitely will either. Just making sure you are aware of the potential. Like I said, not something to be determined over the internet. Looks like you have the correct thinking. Your lumberyard should be able to tell you what size rafters if you give them the spans.
OldNBroken is online now   Reply With Quote
Old 05-17-2012, 03:19 PM   #11
Newbie
 
Join Date: May 2012
Posts: 8
Rewards Points: 10
Default

extend roof over flat roof


thanks for the input. i called building inspector and hes comin over tonight to look at at it.
nate1582 is offline   Reply With Quote
Old 05-19-2012, 07:53 AM   #12
Pro Slate Roofer
 
tinner666's Avatar
 
Join Date: Mar 2005
Location: Richmond, Va.
Posts: 1,607
Rewards Points: 1,030
Default

extend roof over flat roof


I'm not sure I understand where the knee wall is going.

Is it above a support wall?

Triangles are your friend. Not sure of rafter lenght, but if the knee wall is over a support wall, collar ties there create triangles and keep the load centered. ( Collar ties are the pieces that usually ties rafters together on each side of, and below the ridge to keep loads centered on bearing walls without pushing them outwards.)
tinner666 is offline   Reply With Quote
Old 05-19-2012, 08:27 AM   #13
Newbie
 
Join Date: May 2012
Posts: 8
Rewards Points: 10
Default

extend roof over flat roof


the knee wall in center of slope is a mistake. i am not putting that in there. the knee wall at eave where previouse roof pane would be is at a support wall. the length of span from ridge to outter wall is 25 ft. flat roof length is 13 ft. the knee wall will be 2 1/2 ft. i also was told that i need to install collar ties in exsisting gable roof to provide support.
nate1582 is offline   Reply With Quote
Old 05-19-2012, 08:46 AM   #14
Member
 
Join Date: Nov 2011
Location: Hartfield VA
Posts: 27,518
Rewards Points: 4,152
Default

extend roof over flat roof


I often see where a DIY built addition like this has some other issues that could be addresses at the same time as the new roof is installed.

Are both floors even, or is there a step down?
Is the outside wall 8' from floor to ceiling?
Are the ceilings at the same height in both rooms?

I'm thinking if you went with Glue Lams or LVLs you may be able to do without all the center supports.
joecaption is offline   Reply With Quote
Old 05-19-2012, 08:53 AM   #15
Pro Slate Roofer
 
tinner666's Avatar
 
Join Date: Mar 2005
Location: Richmond, Va.
Posts: 1,607
Rewards Points: 1,030
Default

extend roof over flat roof


Sounds right now. Don't just toenail the new rafters to the roof. Remove plaenty of roof area and install one or two 2x10 or 2x12 plates ontot the existing roof deck 'where' the new rafters will land, top and bottom, of course. These will be your nailers. Put plenty of thought into their placement! You have to notch the rafters ends of the rafters about 5" from their points and 1-1/2" deep. The tips of the rafters should land about 2" from the peak of the roof. The sheathing will then line up with the finish point.
Eave will need a different 'set'.

tinner666 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
EPDM - flat roof to sloped roof transition emtaboy Roofing/Siding 12 07-14-2010 01:12 AM
Extend House Roof Over Back Deck Justahome Carpentry 1 04-03-2009 08:25 PM
Flat roof related questions christy123 Roofing/Siding 8 12-10-2008 12:30 AM
Flat roof headache The Barber Roofing/Siding 7 05-17-2008 06:48 PM
Where flat roof meets shingled roof bstyer Roofing/Siding 1 07-07-2005 09:34 PM




Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.