Concrete leveler

[structSU10]

I am trying to do a feasibility study to add a floor to an existing concrete structure. One thing I need to do is level the existing roof. It slopes to a low point of -6", and I am having trouble finding a product that can have a small general thickness near the edges versus the relatively large thickness at the low points. What are typical products that can be used? I see some of the leveling concrete can have pea-gravel added for larger thicknesses, but their cure time also becomes very long and they only reference over 3" which makes me worry about 6 to 7" total.

 

[JedClampett]

If the existing roof is to become an occupied floor, there are many products by Atlas and others that level floors. You might want to fill in the larger places with concrete or lightweight concrete until you get enough in to meet the leveling compound limits. Plus I bet you'll save some money by using cheap plain old concrete in the large gaps and using the compound for just the final leveling.
If this roof is to stay a roof, you should just use tapered insulation.

 

[hokie66]

Agree with Jed. Fill the larger areas with concrete, then use levelling compound. Ardit is one manufacturer, but there are others.

Does the roof have adequate strength for the extra dead load plus floor live load?

 

[structSU10]

Thats what I am looking into. I needed an idea of the minimum extra thickness to get a good estimate of extra dead load. It already appears to be an issues - no help from the grade 40 steel and 3 ksi concrete.

 

[TDIengineer]

Must be nice not having to worry about seismic loading and the added mass. This concept never flies in a high seismic zone. Maybe it has extra lateral capacity.

If columns and spread footings don't figure, settlement is also an issue to watch out for.

Lastly, not sure what building code you are under, but the administrative code in California will require you to bring the entire structure up to code as you will be definitely increasing your overall building mass at that diaphragm by 10%.