If the contractor knows what he or she is doing and knows what the customer wants then the lack of specifications is probably a good thing.
Concrete slab specifications for floors.
Its more than just forms and pouring concrete.
Polished concrete aggregate exposure chart.
Ff and fl numbers floor flatness and levelness.
Floor flatness levelnessone of the things that distinguishes a high tolerance floor is its f number requirement.
To have specification for industry standard without manufacturer bias and produced in a timely manner.
Bre digest 522 parts 1 2 hardcore for supporting ground floors of buildings.
Aci goes further and recommends 4500 psi concrete for garages floor slab.
The international residential code irc lays out a series of requirements for pouring a concrete slab on grade.
F numbers were developed in the 1980s to provide a systematic quantitative way to indicate the flatness and levelness of a concrete floor.
The 4 inch pour of a standard slab is recommended for both garage floors and interior floors.
Standard concrete floor slab thickness in residential construction is 4 inches.
History of concrete floor flatness and floor levelness.
The higher the f number the flatter or more level the floor.
The irc requires that slabs be built with concrete with compressive strengths from 2500 to 3500 psi depending on the climate.
Placed over a 3 4 base of stone stonedust sand whichever is local standard medium broom finish for slabs over 25 x 25 slightly rougher medium broom finish for smaller slabs to minimize tile migration.
Traditionally concrete floors were specified to have a deviation of less than 1 8 over.
03 3543 bonded abrasive polished concrete floors.
To achieve this strength the water cement ratio should be kept at 0 5 or less typically about a 5 inch slump concrete.
Ground bearing concrete floor slabs should be at least 100mm thick including monolithic screed where appropriate.
To prepare the base cut the ground level to the proper depth to allow for the slab thickness.
Floor levelness f l floor flatness f f classifying concrete floors based on flatness and.
Polished concrete appearance chart.
4 slab of 3500 psi concrete.
For both interior floors and garage floors the minimum strength recommendation is 2 500 psi however similarly to slab projects an ideal standard is 4 500 psi especially for garage floors which must sustain much more wear and tear and heavy machinery.
Ground bearing floors shall be of adequate strength and durability and use concrete mixed and reinforced as necessary to support floor loads safely and resist chemical and frost action.
The slab has to be at least 3 5 thick and possibly thicker for expansive or other difficult soils.
Five to six inches is recommended if the concrete will receive occasional heavy loads such as motor homes or garbage trucks.