Making A Flat Roof A Deck?

 
Thread Tools Search this Thread Display Modes
Old 01-13-2004, 08:48 PM   #1
Pro
 
Grumpy's Avatar
 
Trade: Roofing and Gutter Specialist
Join Date: Oct 2003
Location: Chicago
Posts: 8,573
Rewards Points: 2,000
Send a message via AIM to Grumpy

Making A Flat Roof A Deck?


When a customer says to you "I have this flat roof I want to use as a deck" how do you respond? What type of system do you recommend? Assume they are setting no limitations on material or budget.
Grumpy is offline  

Warning: The topics covered on this site include activities in which there exists the potential for serious injury or death. ContractorTalk.com DOES NOT guarantee the accuracy or completeness of any information contained on this site. Always use proper safety precaution and reference reliable outside sources before attempting any construction or remodeling task!

   
 

Old 01-16-2004, 09:43 AM   #2
Pro
 
pgriz's Avatar
 
Trade: Roofer
Join Date: Sep 2003
Location: Montreal, Canada
Posts: 178
Rewards Points: 150

Re: Making A Flat Roof A Deck?


Quote:
Originally Posted by Grumpy
When a customer says to you "I have this flat roof I want to use as a deck" how do you respond? What type of system do you recommend? Assume they are setting no limitations on material or budget.
We have done a few of these. We usually use the most appropriate material for the roof surface itself (torch-on membrane or equivalent), then build a platform on which the deck surface itself is installed. This way, the deck doesn't look like a roof, and there is no foot traffic damage to the roofing material. I know some people install granulated top sheet and claim it is strong enough to support foot traffic, but what if someone puts a chair on this and starts rocking back and forth? You've got a tear in no time.

pgriz is offline  
Old 01-16-2004, 01:54 PM   #3
Pro
 
Grumpy's Avatar
 
Trade: Roofing and Gutter Specialist
Join Date: Oct 2003
Location: Chicago
Posts: 8,573
Rewards Points: 2,000
Send a message via AIM to Grumpy

Re: Making A Flat Roof A Deck?


Pgriz, we usually do a double layer of the modified bitumen torch down. If we do a single layer, we at least install a double layer where the "deck" sleepers make contact with the roof.

If you do use a deck type system it is important that the deck floats and is not fastened to the roof. Also it's important to be aware that the pressure of the deck sleepers on the roof is a common cause of leaks. This is why we do the double layer at the sleepers.

Tom hay was telling me abotu a roof system he installed as a deck a few months back and I wish I could remember the link to the pics. He coated the roof with some kind of material (adhesive maybe?) then sprinkled granuals of some sort on the roof for traction.

Last edited by Grumpy; 01-31-2010 at 03:39 PM.
Grumpy is offline  
Old 01-16-2004, 04:36 PM   #4
Pro
 
pgriz's Avatar
 
Trade: Roofer
Join Date: Sep 2003
Location: Montreal, Canada
Posts: 178
Rewards Points: 150

Re: Making A Flat Roof A Deck?


Quote:
Originally Posted by Grumpy
Pgriz, we usually do a double layer of the modified bitumen torch down. If we do a single layer, we at least install a double layer where the "deck" sleepers make contact with the roof.

If you do use a deck type system it is important that the deck floats and is not fastened to the roof. Also it's important to be aware that the pressure of the deck sleepers on the roof is a common cause of leaks. This is why we do the double layer at the sleepers.

Tom hay was telling me abotu a roof system he installed as a deck a few months back and I wish I could remember the link to the pics. He coated the roof with some kind of material (adhesive maybe?) then sprinkled granuals of some sort on the roof for traction.
You are, of course, perfectly right. Our decks do float, and in fact we use rubber pads to support the deck and hold it separate from the roofing material. As I said, we've done a few and so far no call-backs.
pgriz is offline  
Old 01-17-2004, 10:40 AM   #5
Pro
 
Grumpy's Avatar
 
Trade: Roofing and Gutter Specialist
Join Date: Oct 2003
Location: Chicago
Posts: 8,573
Rewards Points: 2,000
Send a message via AIM to Grumpy

Re: Making A Flat Roof A Deck?


Yeah these roof decks are the things I think about when it rains hard. No call backs here either but I fear they are coming.
Grumpy is offline  
Old 05-06-2009, 09:55 AM   #6
We make dirt...look good
 
Imhotep0357's Avatar
 
Trade: General Contractor - Design/Builder
Join Date: May 2009
Location: Florida
Posts: 9
Rewards Points: 10

Re: Making A Flat Roof A Deck?


Hey guys, this is my first time posting. I'm a young GC out of Florida, and I'm about to build my first deck for a client who is already starting to take apart and analyze my wall sections for the roof deck system. As for the sleepers, do you turn them on edge or lay them flat? Is the double layer of bitumen a good idea with all of the humidity that we experience down here.
Imhotep0357 is offline  
Old 05-06-2009, 11:07 AM   #7
Thom
 
thom's Avatar
 
Trade: General Contractor/Homebuilder
Join Date: Nov 2006
Location: Albuquerque NM
Posts: 4,073
Rewards Points: 3,434

Re: Making A Flat Roof A Deck?


I've done a few. I like the double modified then an asphalt impregnated expansion strip pad(the ones you use with concrete) under the sleepers (flat, not on edge).

You've still got to insure that you are not overloading the roof framing system.
thom is offline  
Old 05-06-2009, 12:05 PM   #8
solar guy
 
naptown CR's Avatar
 
Trade: solar contracting
Join Date: Feb 2009
Location: Annapolis Md
Posts: 1,917
Rewards Points: 1,000

Re: Making A Flat Roof A Deck?


Make sure you have slope for anything you put on the deck at least 1/8 per foot. If they want to do it for a low budget there are a few walkable roof surfaces out there. they look like a vinyl sheet good and are very durable. Also you don't have to worry about sleepers and debris building up between the roof deck and the decking and holding water as it drains toward the edge. The products that come to mind are Duradeck and Deck-king. Just don't use anything thinner than 60 mil. The last roof deck I did was over a torch down roof. I set strips set sleepers on as a double layer. screwed 5/4 timber tech to the sleepers. This was done as a change order and when I got to the county to revise the permit they gave me a really hard time about uplift on the deck as it floated. even there was only a 1 1/2" gap at the lower end for drainage. This was a couple of years ago and I did not know about the duradeck at the time. I ended up paying about 6.00 sq ft for the torch down and additional strips and a fortune for the decking. Could have done the job in duradeck for 8.00 a sq ft and saved a lot. I believe the Deck-king carries a 20 year warranty and is code approved in most jurisdictions as a walkable roof.
Oh yeah as posted above this check your roof framing as it is probably not built for a deck loading. Around here our roof design loads are 20# sf and decks are required to be 60# sf.

Last edited by naptown CR; 05-06-2009 at 12:15 PM. Reason: added text
naptown CR is offline  
The Following User Says Thank You to naptown CR For This Useful Post:
Imhotep0357 (05-06-2009)
Old 05-06-2009, 01:13 PM   #9
We make dirt...look good
 
Imhotep0357's Avatar
 
Trade: General Contractor - Design/Builder
Join Date: May 2009
Location: Florida
Posts: 9
Rewards Points: 10

Re: Making A Flat Roof A Deck?


Yeah, I just got off the phone with my truss supplier, and he thinks that my load is about 65 psf per the FBC. Looks like I'm going to have to get some wood I's to make my 25' span...I'm hoping no deeper than 16" @ 24 o/c. I'm going to research the Duradeck...sounds like a money-saver!
Imhotep0357 is offline  
Old 05-13-2009, 09:52 PM   #10
Pro
 
wellbuilthome's Avatar
 
Trade: building for 30 years. new homes , additions
Join Date: Feb 2008
Location: NY
Posts: 463
Rewards Points: 250

Re: Making A Flat Roof A Deck?


Ive done many torch down roofs with sleepers and they don't seem to hold up for the long haul .
In the traffic ares the rubber get squashed to nothing and starts to leak in 7 to 10 years . We even cut strips of roofing to double up layers and tried 2x6 sleepers .
Now, i like a build up of Epoxy and 3 layers of 16Oz glass cloth. We roll on a high build primer and 2coats of none skid or rubber DURA BAK .
I make the deck posts out of cedar and glass them in and coat them with epoxy You can get the glass and epoxy on EBay in 5 gallon buckets and large rolls . My largest was 12x 20 . Ive done lots of master bed room walk outs 6x6 .
wellbuilthome is offline  
Old 05-13-2009, 10:00 PM   #11
solar guy
 
naptown CR's Avatar
 
Trade: solar contracting
Join Date: Feb 2009
Location: Annapolis Md
Posts: 1,917
Rewards Points: 1,000

Re: Making A Flat Roof A Deck?


Quote:
Originally Posted by wellbuilthome View Post
Now, i like a build up of Epoxy and 3 layers of 16Oz glass cloth. We roll on a high build primer and 2coats of none skid or rubber DURA BAK .
I make the deck posts out of cedar and glass them in and coat them with epoxy You can get the glass and epoxy on EBay in 5 gallon buckets and large rolls . My largest was 12x 20 . Ive done lots of master bed room walk outs 6x6 .
I tore one out that was done this way several years ago. This thing was rotten through the deck and into the rafters. Client wanted mahogany decking so we did double torch down and sleepers. i still like the duradeck or deck-ing
naptown CR is offline  
Old 05-14-2009, 09:46 AM   #12
Pro
 
apehangeralfy's Avatar
 
Trade: Certified Roofing Contractor
Join Date: Oct 2008
Location: Daytona Fl
Posts: 190
Rewards Points: 150

Re: Making A Flat Roof A Deck?


Seal-O-Flex... pink, fabric, pink. Then you can use there top coat and seal or tile directly to it. When done correctly I have not seen one fail.

Torch down is not allowed under a 1/4 pitch here so you have to use an approved "deck" system...
apehangeralfy is offline  
Old 05-14-2009, 10:21 AM   #13
Registered User
 
Hand Bangin's Avatar
 
Trade: Roofing Contractor
Join Date: Mar 2007
Posts: 17
Rewards Points: 10

Re: Making A Flat Roof A Deck?


On my personal deck I used two layers of modified and then came back with Hydro-Stop 4 layer system. I had to replace all the rotten soffit underneath the deck which was a mess. I installed the new roof first to make sure it was water tight......now with the new roof, deck and soffit underneath it seams to be holding up very well. I may have overdone it a little, but I figure spend a little extra now to prolong the life of it.

Hope this helps.
Hand Bangin is offline  
Old 05-15-2009, 09:42 AM   #14
Pro
 
dougger222's Avatar
 
Trade: Roofing Contractor
Join Date: Jan 2004
Location: Stillwater Minnesota
Posts: 1,648
Rewards Points: 1,056

Re: Making A Flat Roof A Deck?


My father and I have roofed a few flat roofs for builders which had decks built on top. One we didn't like as they had an opening in the middle for the water to drain. The idea was they didn't want any gutters on the front of the house. We made it work but it was a pain.

On my own home we recently did a flat roof/deck on the balcony off the master bedroom. The builder put down rubber roofing and decking on top which leaked in a few spots on the ceiling underneath. My idea was to put a roof system down that never needed to be done as long as I owned the house. Here's what we did,

First we put a layer of 1/2 inch plywood over the rubber roofing. After walking on it it was decided another layer of 1/2in plywood would help firm up the deck. We removed the hardi board siding against the wall and cut up the hardi board on the four pillars to allow our roofing product to lap up on the walls/pillars 6 inches. Then we put a layer of Winterguard on it and base sheet on top of that. Next we put down smooth torch. From there my tile guy took over and put down slate tile which turned out amazing. My father came back and did the shoe around the base of the pillars. Now waiting on my wife to pick out a railing system.
dougger222 is offline  
Old 05-15-2009, 05:28 PM   #15
Member
 
Gilby's Avatar
 
Trade: Roofing Contractor
Join Date: May 2009
Location: NW, OH
Posts: 77
Rewards Points: 75

Re: Making A Flat Roof A Deck?


I lay duro-last and it is probably your best bet to put a deck on. It is durable and best of all its completely clean. Its never dirty. You mechanically fasten it down and heat weld all the seams together. We use this all the time for that sort of thing.
Gilby is offline  
Old 05-15-2009, 07:22 PM   #16
Pro
 
dougger222's Avatar
 
Trade: Roofing Contractor
Join Date: Jan 2004
Location: Stillwater Minnesota
Posts: 1,648
Rewards Points: 1,056

Re: Making A Flat Roof A Deck?


My Uncle worked for a roofing outfit that was certified to install Durolast. He said the company on average charges $1,000 per square labor and materials for new construction.

Just looked at a roof that had it on the roof above the indoor pool.

Isn't this just another of the many thin rubber like flat roofing products with a life expectancy of 10-15 years?
dougger222 is offline  
Old 05-15-2009, 08:01 PM   #17
Pro
 
J-Peffer's Avatar
 
Trade: Roofing & Siding Contractor
Join Date: Mar 2007
Posts: 403
Rewards Points: 250

Re: Making A Flat Roof A Deck?


Flat roofs seem bad enough, but then people want to walk on them too!

Just does not seem like it can last too awfully long, and really could make it a expensive repair to fix if it starts to leak or needs to be replaced.
J-Peffer is offline  
Old 05-15-2009, 08:24 PM   #18
Pro
 
Ed the Roofer's Avatar
 
Trade: Roofing Contractor
Join Date: Dec 2006
Location: NW Suburbs of Chicago
Posts: 7,135
Rewards Points: 2,010

Re: Making A Flat Roof A Deck?


Quote:
Originally Posted by dougger222 View Post
My Uncle worked for a roofing outfit that was certified to install Durolast. He said the company on average charges $1,000 per square labor and materials for new construction.

Just looked at a roof that had it on the roof above the indoor pool.

Isn't this just another of the many thin rubber like flat roofing products with a life expectancy of 10-15 years?
Duro-Last is a Hybrid copolymer pvc alloy, which means it is a white membrane reinforced with a polyester scrim.

It's standard mill thickness is stated as .040 mills, but is actually closer to .037 mills thick.

If you have no sharp objects that will rest on it, and if the tech using the hot air welder knows how to seam weld properly, the roof will last it's warranty length. They offer a 15 year unlimited or a 20 year pro-rated after the first 10 years warranty. Oh, it does come in other colors too, but they are not your typical order, such as Grey, Tan and a new one that I can not recall at the moment.

The main problems deflected at Duro-Last installations, are the sloppy bagginess that some contractors do not know how to pull the wrinkles out and also the continual turn over of their Quality Control Inspectors.

Also, since the sheets are pre-fabricated to the size of your roof order, up to 20 squares large, the 5 foot wide panels are pre-seamed with a dielectric welding process at the manufacturing and fabrication facility.

There are many rumors from other contractors, that state that the attachment at this dielectric weld, when pulled as taut as necessary to achieve a tight looking roof surface, have split apart. Also, spider-webbing cracks have been commonly reported to occur after the installation has weathered for some time.

I did not ever see either of those problems exasperate themselves on probably around 2,000 installations that I did with that brand of product, but the tearing at the dielectric weld potential did cross my mind.

Ed
Ed the Roofer is offline  
Old 05-16-2009, 04:33 PM   #19
Member
 
BULLHART's Avatar
 
Trade: Commercial Roofing Inspector/ Trainer
Join Date: Oct 2006
Location: Flowery Branch, GA
Posts: 90
Rewards Points: 75

Re: Making A Flat Roof A Deck?


I prefer a ashpalt hybrid for this one. Maybe a 3 ply built up with a Modified Cap.
BULLHART is offline  
Old 05-16-2009, 08:22 PM   #20
Pro
 
wellbuilthome's Avatar
 
Trade: building for 30 years. new homes , additions
Join Date: Feb 2008
Location: NY
Posts: 463
Rewards Points: 250

Re: Making A Flat Roof A Deck?


Quote:
Originally Posted by naptown CR View Post
I tore one out that was done this way several years ago. This thing was rotten through the deck and into the rafters. Client wanted mahogany decking so we did double torch down and sleepers. i still like the duradeck or deck-ing
I haven't had any callbacks on my glass roof jobs yet . The first one was done in 1997 . I have been back to change the color on one and replace the none skid. It still looks like new . I mite try the dura deck next time .
John

wellbuilthome is offline  


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

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
Torch down(flat roof) leaks BAD...can you give advice ASAP? Detail Guy Roofing 22 01-05-2013 05:42 PM
Deck over a flat roof Same Old Construction 10 12-07-2011 01:28 PM
Low Pitch Roof solutions Fixer Roofing 4 02-18-2007 10:09 AM
Flat roof over garage leaking under exterior walk out door IHI Roofing 18 05-30-2006 09:28 PM
Do You Need A New Roof ??? Perfect Roofing Roofing 0 02-10-2005 01:46 AM

Join Now... It's Fast and FREE!

I am a professional contractor
I am a DIY Homeowner
Drywall Talk is for
PROFESSIONAL CONTRACTORS ONLY!

At DrywallTalk.com we cater exlusivly to professional contractors who make their living as a contractor. Knowing that many homeowners and DIYers are looking for a community to call home, we've created www.DIYChatroom.com DIY Chatroom is full of helpful advices and perfect for DIY homeowners.

Redirecing in 10 seconds
No Thanks
terms of service

Already Have an Account?