ticas...that's too "open ended". Where is the project located? Is the deck structural concrete or lightweight insulating concrete? Are there internal drains or will drainage be over the edge of the roof? Is there insulation required? Is there a slope requirement? Will there be equipment located on the roof? Will maintenance access be required?
All of these (and more) are variables that must be considered before selecting a roof membrane system.
deck is structural concrete, 4 inches slab with average span of 3 meters. There are drainage holes at the edge of the roof. Waterproof required to prevent water or moisture from seeping down the concrete roof. No equipments on roof. Since it's a roofdeck with 100 psf live load, it can support telescope viewing at night or camping. So cement will be put on top of the member.
So what is the best membrane. Is there one that can double as heat insulation? Thanks.
"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning."
roofing is not a product, its a system with many parts. membrane, adhesives, flashing, reinforcement and cover as well as drains and scuppers. all working together with specified performance. I would recommend discussing with a roofing contractor to get a better feel for your options.
ticas...you have implied that this will be a traffic membrane application, since you'll have pedestrian traffic and viewing areas up there.
This would not be recommended for a typical roof membrane system as there is almost always an attempt to reduce the amount of walking on the roof surface as this can damage it.
For your application, I would look at several options:
1. A membrane system that will handle pedestrian traffic. Something like a Vulkem 351 system is good for this. Other manufacturers have similar fluid applied urethane systems that can be reinforced with a polyester or glass fiber scrim.
2. A typical membrane roof system (PVC, TPO, Modified Bitumen, etc.) with pavers installed over the roof membrane system.
For either system you could install insulated pavers to improve the energy efficiency, keeping in mind that it won't be a large insulation value, but some.
If you are going to have pedestrian traffic on the roof, pay close attention to placement of guardrails and other safety features.
Roofs are very much subject to Owner preferences and prejudices.
I would check out what kind of roofs the Owner already has. If there is a similar structure, ask how they feel about maintaining another one of those roofs.
if your structure can hold it and it doesn't blow your cost, you could put a topping slab above a waterproofing layer, which would open the door to a whole bunch more products (sheet waterproofing, elastomeric, crystalline, etc...), and give you design flexibility for the recreational use. Also, you wouldn't get the UV damage. If you do this approach, check that the topping slab won't move. insulation could be over the waterproofing or on the interior, constraints being condensation possibility & space for interior and drainage & long-term structural integrity for exterior approach.
