Using Rubber To Waterproof a Flat Roof | This Old House 

Very interesting, thanks for the full video

Although the basic installation is correct and fine for that area of the country. Tom mentioned wind uplift. The perimeter edge is the most vulnerable to wind damage. As an experienced roofer here on the coast of Wilmington NC I’ve seen roof damage from the results of multiple hurricanes. The biggest cause of low slope failures is because the perimeter edge failed. Drip edge should always be installed as tight to the facia as possible, as long as the face is less than 4” wide. Cleated if wider. We utilize a continuous metal cleat ,the same profile as the drip edge and one gauge heavier, of the same type of metal or as we do, stainless steel for all cleats. It’s attached through the the face of the cleat just above the kick out with either screws or stainless steel, ring shank roofing nails, 6” on center. The drip is then hooked to the cleat at the bottom by an open hem. Then the drip edge is nailed on the roof side 3” on center in a staggered pattern. The roof may fail from other causes but the perimeter edge will not. Another thing I strongly disagree w with is the soft substrate. The high density Poly-iso is s designed cover board for the purposes of sphere ing membrane . Its about 80 psi in compressibility, regular ISO 20 psi. The harder the substrate the less damage from debris. EPDM is easily penetrated by falling debris. The softer the substrate the larger the penetration through the membrane. Harder substrates prevent bigger penetration and less damage. A gypsum board made for roofing applications such as DensDeck or SecuRock is the best protection from flying debris. Both these material also have the highest wind uplift resistance for any substrate if secured properly to the roof deck. For instance , 1/2’SecuRock over a 1/2” plywood deck with 18 plates and screw in each 4’x8’ board and fully and self adhered TPO membrane has a wind uplift resistance of -135 PSF from information gather from testing by our manufacturer. Ive been a fn since the show went on the air, I have the greatest respect for Tom. TOH is far and above any other in knowledge and professional building techniques. Roofing is my profession. Need another host? Seriously check into modern low slope roof design. It ain’t the hot asphalt I started in 40+ years ago. There’s some remarkable products and installation practices out there.

FANTASTIC!!!

Great video

Awesome

What is the best way to waterproof hollowcore slab roof top terrace.. i wanted final covering to be natural stone..so what should go on top of slab and how to lay tiles at the end?

Any recommendations for a good roofer company in/near Hayward CA for residential house single story, low pitch. I have shingles installed before I bought house. Thank you for video

Finally something im better at than Tom!

Back in the 80's I learned how to do torch down roofing. On my first full roof, I was using the torch for almost 8 hours with a half hour lunch. That night I dreamed for what felt like another 8 hours that I was on that same job. I woke up feeling like I had just finished a 16 hour shift, torching down a roof. I went back to carpentry after that.

Contact adhesive? How do you get any air bubbles out? Do this big washers not cause problems?

In CA 3"1/2 and above is a pitch roof.

What kind of adhesive is that?

how do you install and waterproof a skylight on an existing torch down flat roof

Can this be done on a mobile home in South-Central NY State? I've been using Silver Seal and it just doesn't work as well as I'd like.

so you extend the metal drip edge slightly out, to protect the fascia? wouldn't capillary action draw water up and under the drip edge then? or is the 45 degree angle enough to drive water off

Tommy I hope you reply. live in apt and roof keep leaking into apt, first it was closet in foyer, black mold,..owners to re did the closet knock down all sheet rock to repair. then the water started leaking into kitchen every rain storm. biggest hole that was cut was 2' by 3 inches to repair. this has been over 6 times in the kitchen. then it happened in the living room I watched the cracks in ceiling open up during a rain storm had about 20 plastic shoe boxes catching the rain.. owners dropped the ceiling. now its happening in the bedroom as I type, this. its the other end of the apt. Im worried ceiling is going to fall. I know you out here will say move...Its not that easy for me right now. they pay HPD inspectors to NOT violate them. An Inspector himself saw the cracks said its ok its wear and tear of building, just 2 weeks ago. but he was wrong. they same people they pay to keep quiet NYC inspectors are the same guys who come back to say it was properly repaired. Its leaking into hallway of building too. they keep layering the roof with more and more rolls of membrane. roof looks bowed as if too heavy. I don't think it is suppose to look that way inside apt.please everyone be kind in your replies.

We have a sunroom that is extremely loud when it rains heavily. This looks like it would really deaden the sound. Is there anyone in St. Louis that you would recommend to install this?

My garage roof have a slope of 2 degrees.

One critical question stands out in my mind. UV rays and nature (wind, water, heat, cold) would seem likely to degrade rubber rather quickly. I just want to confirm that there is no additional material on top of the rubber? If not, it would seem that the rubber will lack durability.

What's the life span of that rubber? What happens when it breaks down and you need to replace it? Do you just cover with another layer?

you have to prime the strip in

Recommend flashing in the gap between the foam and the furring strips because if the rubber does so happen to suffer a tear, the water will be able to run off.

3:12 pitch is not flat! It's low-slope. Anything more than 2:12 CAN be shingled with the correct ice/water barrier. 4:12 is generally the break point where barriers are not required with shingles

Anyone know what the cost for this is versus other flat roof membranes that can be used? What’s the life span, durability, efficiency?

Why put the wood around the perimeter of the iso-board? Wouldn't that suffer from the same "too hard" problem the iso-board is intended to solve? So your rubber sheet would just be inclined to get punctured where it sits over the wood?

"3 inches up over 12 inches, or 7 inches up over 24 inches" Now I'm not a mathologist, but...

Do you suggest a rubber roof liquid coating? EPDM?

I need your help please let me know how I can contact you because you can only understand it better via images. Quick brief is we have a tree going through our glass roof and we need to waterproof the opening of the tree keeping movement of tree in mind via wind pressure

Compared to shingles that roof looks like it could easily be damaged by falling branches.

U forget put base sheet mr

How come you don't use a latex glue ,I've put on quite a few,also there is a nother roof material it's called TPO much much tougher ,by the way retired RV mechanic 44 years ✌

Look at Tommy still has them man hands, dry skin and all. Thanks, Uncle Tommy for all the lessons!

I have flutter (same type of roof) Does this mean they did not glue it down ???

Is the rubber also known as the TPO?

3.5 inches over 12 is "flat" ... wow, my roof (and most roofs around here) are most certainly flatter than that. A 50' front to back house would be over 14 feet taller on one side if that was the case.

What about a flat concrete garage roof that is also used as a patio/porch? In other words there is foot traffic on it. There is one drain in the middle but not a good slope anywhere.

Peace.. Salam... Shalom.. Namaste...Thank You so much for All that you are doing to Heal our Mother Earth 🙏🏻 😊 🌈 ✌ 🌷 ❤

EPDM fine over plywood.

Do you have to get exact dimensions to cover the roof with a single piece? How do you deal with side by side seams?

IF AN UNVENTED ATTIC ASSEMBLY IS DESIRED IN ADDTITION TO COVERING THE ENTIRE ZIP SYSTEM SHEATHING WITH AN ICE AND WATER MEMBRANE, HUBER ENGINEERED WOODS HIGHLY RECOMMENDEDS CONSULTING A BUILDING SCIENCE OR INSULATION SPECIALIST PRIOR TO INSTALLATION. - from their documentation.

And how come your not using the white TPX on a residential? Did the owner not want to pay the extra money?

A 26-ga or 24-ga metal roof would be much better.

You should use cured cover strip on the metal. Uncured will not hold up to the life of the epdm

3/12 pitch aint flat. Come to Florida where 2/12 is common

I'd paint it with the most reflective paint on the market. Black roofs are a no-no.

Pat L building regulations call for a minimum of 5" (150mm) insulation. The inspector would not pass this roof.

vinyl better

Torch would be much better 👌

How long before that rubber is destroyed by the sun?

Not suggested where it rains-ask me how I know

How come you don’t attach the flashing over a 1x2 or a 2x2

Sorry Tommy, you got 50% of the info you presented correct.

It really seems America is years behind Europe with flat roof Epdm roof covering technology. The edging strips used now are two piece and provide a drip edge directly into the gutter and are not nailed do the nails never pass through the epdm. The adhesive used is also not a contact one so the rubber can be brushed flat to remove air pockets. Contact glues are generally used on the 50-80 mm edge overlay.

I'm a TOH fan, but I have never been a fan of flat roofs, period.

Use 60 Mil EPDM and you don't have to piss away your money on labor and material to prevent "falling limbs" ??

Could have installed a metal roof. .

Roofing just sucks

Im a flat roofing specialist and his information is wrong

bought an old house with 3 low roofs with parapets. Its destroying my life. Considering taking down the parapets and going with this system

nail penatraite rubber

technically there is no flat roofs cause you need at least a few degrees for the water not to get stuck in there

Flat roofs are ugly and are always a pain in the long term.

For years I've been so disappointed in TOH team for laziness in regards to what is shown on flat Roofing. From my perspective of a commercial Roofing contractor when watching TOH tv it appears they demonstrate proper building means and methods. I am a total idoit to residential building materials, methods or carpentry. So I've assumed what they are showing is top notch, cutting edge pushing the limits of technology. But then when I watch flat Roofing segments I am so embarrassed for TOH. If they had just asked a local flat roofer or read some free literature on NRCA web site simply following Industry standards. Make me wonder about everything else they show. Maybe what their showing is not as good as I thought or the best way.

Crap materials. Sad.