Details and photos of residential flat roof in action

Some folks have asked us how the roof will be constructed, since there aren't too many of the flat roofs on houses around here. Well, you actually do see them everywhere, but they are found on commercial buildings and according to the roofer guy we talked to (Pepe at Pro-tect Roofing Services), they are much better made and last 5 times more than the conventional, heat absorbing dark gray asphalt tiled roofs. They are a little more expensive to build, but not enough to offset the energy efficient and durability benefits of this roof. I will post prices once I get them from Pepe.

I was lucky enough to be able to get on top of a roof while it was being done. Pepe let me see his work and he's a prospective roofing sub that we want to hire. He was very knowledgeable, as well as nice and helpful and not condescending like many of them can be - especially to a female. He wanted me to witness his workmanship in person, which says a lot about him. Anyway, I took some photos to help you understand how this will be done (and it WON'T leak!). I took some pictures of the roof he's working on (not our house in these pics, sorry!). This is called a commercial grade, residential flat roof/low slope taper roof system using a single-ply membrane:


First, our roof will be an 8.5" SIP panel (foam sandwiched between OSB wood boards, see earlier post about this), then styrofoam wedges (see A) are attached to the SIP that will give a pitch or slope (see B).

The Tyvek house wrap goes above and over the parapet wall (see C). Then the single-ply membrane is rolled over the styrofoam wedges and attached using screw attachments (see silver round attachments in D-E). Pieces of the membrane are layed up on top of the parapet wall (see H on the left parapet wall) and also cover the screw attachments (see E) and then roofing adhesive is used to adhere the membrane to the parapet (see F-H). Finally, all edges and seams are heat-sealed using this hot melding tool (see I, sorry, I don't know the official name of this thing!).

It has a 1/4" slope for every foot, so it's VERY gradual, but enough to drain out the water on the roof. Since we are doing rainwater collection, this is very important and the single-ply membrane must be safe for drinking water. We found a really good brand called Duro-Last that is a reinforced polyvinyl chloride polymer and comes in 40 mil and 50 mil thickness, which is safe for rainwater collection. If you go on their website, there is a lot of technical specs for those that need to know the chemical makeup and information on finding a contractor near you.

If you look carefully at the far edge (click on the picture to enlarge), you can kinda see the low slope in the following photo. Also, we will have a much higher parapet wall then this house, but it gives you a good idea:

Pepe says this is a superior construction to using tiled roofs. The ceramic tiles you see on Mediterranean homes are VERY expensive and high maintenance, and this one in comparison is very low maintenance and lasts 5 times longer. Not only that, but the foam adds added insulation to your roof (even if not using SIPs) and the white or light colored single-ply membrane reflects a lot of heat giving you a very sweet, energy efficient home.

Here's a pic of how it looks on the side of the house (see A) and see how nice and clean it looks, as you don't see an ugly roof when you look at the house (I am biased towards not showing roofs, and don't care for the A-line/many gables look). Also look at how creative you can be with the underside (see B) of the roof, by adding lights or wood siding to give it an architectural element.



You can also mount solar panels on here as well as have rain water collection, adding to the greenness of your home. Note that if you do add solar panels, make sure a professional roofer is on hand with commercial experience to seal the attachments of the solar panels with the same method explained above with the parapet wall. You don't want your single-ply membrane to be punctured or damaged!