1/4":12 Slope - Can I Go Metal Or Must I Use Modified Bitumen - Roofing/Siding - DIY Home Improvement | DIYChatroom


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

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

Reply
 
Thread Tools Display Modes
Old 09-21-2013, 12:49 AM   #1
Newbie
 
Join Date: Sep 2013
Location: Albuquerque, NM
Posts: 10
Rewards Points: 10
Default

1/4":12 Slope - Can I go Metal or must I use Modified Bitumen


Building an attached Pergola patio cover with solid roof onto one-story home (20' x 14' or 280 sqft). Existing roof has shingles, but I was wanting metal on my patio cover for it's longevity. Any options for a metal roof if I stick with a 1/4" slope? I know, I know it's like a flat roof. I don't have height to spare, sorry. Am I correct in thinking modified will run me about the same price as metal, professionally installed?

Advertisement

misshoop is offline   Reply With Quote
Old 09-21-2013, 09:47 AM   #2
Member
 
Join Date: Nov 2012
Location: Hamilton, Ontario
Posts: 227
Rewards Points: 200
Default

1/4":12 Slope - Can I go Metal or must I use Modified Bitumen


The only metal that you could use on that slope would be very expensive.
Modified isn't your only option, but its a good one. 3 ply modified is a good roof, in my area tends to last 15ish years, but ive seen quite a few older.
Why don't you gable it off and add slope that way? Tie it in with valleys, have shingles to match the main house. Some of the increased building costs would be offset by the far cheaper roofing.

Advertisement

PatChap is online now   Reply With Quote
The Following 2 Users Say Thank You to PatChap For This Useful Post:
joecaption (09-21-2013), misshoop (09-24-2013)
Old 09-21-2013, 09:46 PM   #3
Member
 
Join Date: Nov 2011
Location: Hartfield VA
Posts: 27,812
Rewards Points: 740
Default

1/4":12 Slope - Can I go Metal or must I use Modified Bitumen


Need at least a 2 slope for metal roofing.
__________________
When posting in forums, letting us know your location will help others give better feedback/advice/solutions to your questions
joecaption is online now   Reply With Quote
The Following User Says Thank You to joecaption For This Useful Post:
misshoop (09-24-2013)
Old 09-24-2013, 11:11 PM   #4
Newbie
 
Join Date: Sep 2013
Location: Albuquerque, NM
Posts: 10
Rewards Points: 10
Default

1/4":12 Slope - Can I go Metal or must I use Modified Bitumen


Unfortunately, I can't Gable our patio due to HOA restrictions.
misshoop is offline   Reply With Quote
Old 09-27-2013, 11:59 AM   #5
Member
 
Join Date: Oct 2009
Location: Albuquerque NM
Posts: 149
Rewards Points: 75
Default

1/4":12 Slope - Can I go Metal or must I use Modified Bitumen


misshoop -
According to ABQ patio cover requirements, we can do 1/2:12 with metal roofing. That's what I'm doing. According to the builders/roofers I've talked to around here, it's not a problem. Some of the builders might even be able to get 1/4:12 approved, but I'm going for 1/2:12. With 1/4:12 you can use Simpson joist hangers, but at 1/2:12 they're not rated. BTW, I'm planning to use Alvarado Roofing for the roof.
Check your PM.
garya505 is offline   Reply With Quote
The Following User Says Thank You to garya505 For This Useful Post:
misshoop (09-27-2013)
Old 09-27-2013, 03:30 PM   #6
Metal Roofing
 
Join Date: Jan 2012
Location: Mission Viejo, CA
Posts: 539
Rewards Points: 552
Default

1/4":12 Slope - Can I go Metal or must I use Modified Bitumen


Quote:
Originally Posted by misshoop View Post
Am I correct in thinking modified will run me about the same price as metal, professionally installed?
Heck no, Metal will be 2x to 3x the cost of Modbit. But metal will look 5x better then modbit.

I think MBCI has a SS that can go to .25/12, probably a double lock or field seam type install. I am sure there are more companies if you look, or head over to the MRA website and ask.

sorry my bad .5/12 or greater, the .25 is fugly

From the MBCI site:
BattenLok® HS and SuperLok® must be installed on roof slopes of ½:12 or greater.

Last edited by AndyWRS; 09-27-2013 at 03:49 PM. Reason: Links
AndyWRS is offline   Reply With Quote
Old 09-27-2013, 04:26 PM   #7
Newbie
 
Join Date: Sep 2013
Location: Albuquerque, NM
Posts: 10
Rewards Points: 10
Default

1/4":12 Slope - Can I go Metal or must I use Modified Bitumen


Thanks for the replies! Going to with a modbit to keep the 1/4 slope. It should be approved by my HOA, and I can get away with 3.5" step down vs. 6"! Really appreciate the impute!

PS: Anyone good with math and can help me calculating the cuts for my raters?
misshoop is offline   Reply With Quote
Old 09-27-2013, 07:03 PM   #8
MEASURE ONCE, CUT TWICE
 
123pugsy's Avatar
 
Join Date: Oct 2012
Location: MARKHAM, ON
Posts: 648
Rewards Points: 722
Default

1/4":12 Slope - Can I go Metal or must I use Modified Bitumen


Quote:
Originally Posted by misshoop View Post

PS: Anyone good with math and can help me calculating the cuts for my raters?
End cut 88.8 degrees.
123pugsy is online now   Reply With Quote
Old 09-28-2013, 06:12 PM   #9
Roofmaster
 
Join Date: Oct 2012
Location: Maryland
Posts: 3,669
Rewards Points: 2,096
Default

1/4":12 Slope - Can I go Metal or must I use Modified Bitumen


You can use a true single ply also, like EPDM, or a thermoplastic. Some metal roofs can be used as low as 1/4 12, but they all have sealant in the seams. I would not use metal at that low of a slope. A two ply Modified over a glass base sheet would be good, but I would use cold process or hot asphalt at least for the first ply, because of the risk of fire. 1/4 inch in 12 is even low for mod bit because of the overlaps.
__________________
" A lot of men build things, and a lot of things fall down "

jagans is offline   Reply With Quote
The Following User Says Thank You to jagans For This Useful Post:
misshoop (09-28-2013)
Old 09-28-2013, 08:17 PM   #10
Member
 
Join Date: Jul 2008
Location: NJ
Posts: 267
Rewards Points: 272
Default

1/4":12 Slope - Can I go Metal or must I use Modified Bitumen


1/4:12 slope metal roofing is quite common but it's typically mechanically seamed with a higher profile leg. Here's one: http://www.ziprib.com/admin/singlepd...e-June2012.pdf

Advertisement

rustyjames is online now   Reply With Quote
The Following User Says Thank You to rustyjames For This Useful Post:
misshoop (09-28-2013)
Reply


Thread Tools
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 vs Modified Bitumen for flat roof arubatan Roofing/Siding 16 11-19-2008 07:50 AM
Modified Bitumen or roll roofing Ricardo Roofing/Siding 7 05-08-2008 07:38 AM
Modified bitumen vs 60 mil EPDM membrane Flat Roof doingygirl Roofing/Siding 11 01-07-2008 09:41 AM
Tar & Gravel vs. Modified Bitumen ($13k or $7k) ?? Roscoe Roofing/Siding 6 10-10-2006 09:34 AM
Adding granules to smooth modified bitumen KCnorthernCA Roofing/Siding 7 06-22-2006 06:25 PM




Top of Page | View New Posts