Nrdca gypsum roof deck repair replacement procedure.
Lightweight concree roof deck.
Lightweight roof deck concrete is self curing under most conditions.
The end result of the structural lightweight mix is a deck that can be 20 25 lighter than standard structural concrete.
The normal weight concrete employs standard aggregates i e.
With standard structural concrete the aggregate used is sand and stone.
Hard rocks with a low water absorption rate and weighs approximately 2403 kg m 3 150 lb cf.
Picture story of gypsum roof deck repair sequence.
Lightweight insulating concrete decks.
Vermiculite concrete is highly adaptable for concrete roof systems.
Lightweight insulating concrete low density non structural concrete comprised using ultra lightweight expanded mineral aggregates or preformed foam.
These floors are constructed for different purposes but the reduction of dead loads on the structure is the main motivation behind using this system.
Lightweight insulating concrete lwic is batched on site and used to encapsulate expanded polystyrene insulation to provide permanent roof insulation and slope to drain.
Structural concrete composite deck.
However when a lightweight structural concrete lwsc roof deck is poured in place it uses significantly more water.
Nrdca 250 field quality control procedures for application of insulating concrete roof deck systems.
Vermiculite for roof decks can be placed over various kinds of form boards fiber fiberglass acoustical and asbestos cement as well as over paper back wire lath.
Compressive strengths from 125 350 psi are common for lwic used in roof deck construction.
Lwic can be placed atop any of the above mentioned concrete deck types or.
However moist curing is preferable.
The lighter the concrete the better lower the k factor.
The steel deck panels are embossed in a manner which when filled with concrete.
Nrdca 300 procedures to determine the accuracy of material measuring equipment for lightweight insulating concrete.
Repaired areas exposed to high temperatures direct sunlight or extremely windy conditions should be lightly misted with water or covered with damp burlap for 24 hours.
Lightweight insulating concrete roof decks are high performance roof insulation systems that reduce roof maintenance and replacement costs.
What are the different types of concrete roof decks.
Lightweight insulating concrete lwic is defined as having oven dry unit weights of 50 lbs ft or less.
Lightweight concrete roof decks can withstand these high and sometimes relentless winds reducing the amount of damage to the roof.
In addition to being one of the highest rated forms of roof decks concrete decks are also highly cost effective.
With structural lightweight concrete a mix of shale slate slag and clay are used and with this mix the aggregate is fully saturated prior to mixing.
