Calculating Slope For Patio Cover - Carpentry - DIY Chatroom Home Improvement Forum

 DIY Chatroom Home Improvement Forum calculating slope for patio cover
 Register Blogs Articles Rewards Search Today's Posts Mark Forums Read

01-07-2009, 01:42 PM   #1
Newbie

Join Date: Jan 2009
Posts: 3
Rewards Points: 10

## calculating slope for patio cover

I am in the process of of DIY Patio Cover. I got the main support attached to the house and ready to start putting on the four support beams but have to calculate the slope. Can someone explain a way to do this in easy DIY terms.

Here is what i got.

I have the main 2" x 6" x 16' beam attached to the house 8' - 3 1/4" high flush right under the soffit. The beam is actually 5 3/4" not 6"

The support beams 2 x 6, will extend out 9' and rest on the support post that are 7' - 3" high.

What would be the slope? How do i get this figure?

Geometry Challenged.

Dave

01-07-2009, 02:12 PM   #2
Not so new

Join Date: Nov 2008
Location: Lehigh Valley, Pa.
Posts: 954
Rewards Points: 520

ep...welcome. I assume you want you want to know the angle to cut the rafters where they meet your ledger board? I come up with about 87 deg. Cant be exact because I'm not there. Cut it at 87 and then put it up and check it. If its off, scribe it and recut. Good luck.

01-07-2009, 04:48 PM   #3
Newbie

Join Date: Jan 2009
Posts: 3
Rewards Points: 10

## slope

Thanks Penny. how did you get to this figure.

dave

 01-07-2009, 07:37 PM #4 Not so new     Join Date: Nov 2008 Location: Lehigh Valley, Pa. Posts: 954 Rewards Points: 520 Drew it on Deltacad and measured the angle. My calculator's in the truck and its raining outside. I cant imagine anybody could explain how to figure it in a forum. Go to your local lumber yard and ask for a ConstructionMaster calculator. Does everything from rafters to stairs. Good luck!
01-08-2009, 09:42 PM   #5
Newbie

Join Date: Jan 2009
Posts: 3
Rewards Points: 10

## slope

did you mean .87 or 8.7, 87 degrees sounds a bit much?

 01-09-2009, 07:14 AM #6 Not so new     Join Date: Nov 2008 Location: Lehigh Valley, Pa. Posts: 954 Rewards Points: 520 I guess its all in how you look at it. I should probably have answered 3 deg. Put your speed square on your rafter. Pivot speed square to 3 degrees and draw your line. I may have been confusing, sorry. Make sure your crowns are up and scribe if you have to.
 01-09-2009, 02:03 PM #7 Remodeling Contractor   Join Date: Dec 2008 Location: Sandy Hook, CT Posts: 3,590 Rewards Points: 2,000 Break it up into a right triangle. so if the height is 8'3/4" - 7'3' The leg of the triangle is (a) 1'3/4" The base of your triangle is 9 the angled side (hypotenuse) is 13'6" So the arcsine (header down) is 83.22 degrees. The angle above your post is 6.78 degrees. Or you can think of this as a simple stair rise. The 1'3/4 is the rise 9 foot the run
01-21-2009, 10:22 AM   #8
Home Improvment Contactor

Join Date: Jan 2009
Posts: 35
Rewards Points: 25

Slope equals rise over run. Run is half your span. Span is the total width of the house. Rise is the total height of the roof from the top of the wall framing. So that means that... Span x .5 = Run. Rise divided by run = slope. I think I remembered that right.

There is 180 deg. in a right triangle. So if you have the figures for two of the angles the third should be the remainder out of 180.
A squared + B squared = C squared

Last edited by Jack of most; 01-21-2009 at 10:31 AM.

 Thread Tools Display Modes Linear Mode

 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 OffTrackbacks are Off Pingbacks are Off Refbacks are Off Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post hartkem HVAC 5 11-24-2008 08:38 AM 2picky Remodeling 3 11-15-2008 04:05 PM bcme136 HVAC 14 09-25-2008 06:34 PM brianbh Roofing/Siding 10 02-11-2008 07:34 PM Jackhammer Building & Construction 3 07-10-2007 03:49 PM

Top of Page | View New Posts