Who installed your radiant floor slab.
Floor measurement top of slab to top of slabs.
This includes backing top design and protective layers.
Did the builder forget to install poly under the slab.
This vinyl type comes in a single sheet that is installed over the concrete floor.
As with f l the measurements are linear and higher numbers represent a flatter floor.
On commercial jobs raw slabs are frequently treated with sealers which may cause adhesion problems.
Floor flatness tends to be very important for spaces where equipment must be set perfectly.
We aim to reduce the weight of the slabs to bring down costs reduce transport loads and craneage where possible.
Adhering to the astm standard and installing rh sensors every 1 000 square feet is the only way to go to ensure greatest testing reliability.
Exclude concrete at junctions with slabs of same concrete grade i e.
Open top of wall.
For example a floor with an f f measurement of 60 is twice as flat as a floor with an f f of 30.
Astm f2170 rh testing inside the concrete slab the in situ rh test provides a numeric measurement of the moisture within a concrete slab using an rh sensor placed at a specific depth.
Exclude formwork intersected by slabs.
Even if the builder forgot to install poly under the slab there.
If they bead up on top of the slab it is probably contaminated.
A range of sizes and configurations are possible with wide slabs so our designers ensure that each project is individually designed for application and loadings.
Top of slab above i e.
The calcium chloride test or mver has been shown to measure moisture conditions in the top inches of the slab only.
Slab measured across wall.
Most residential slabs have a layer of 6 mil poly or a similar thicker vapor barrier membrane directly under the slab.
Soffit of transfer structure slab or beam above.
F f numbers can be taken for slabs on grade as well as elevated slabs.
No surface test tells an installer how much moisture is present deeper within the concrete which is critically important as that moisture gradient will equalize if a non permeable floor covering is installed.
Do not exclude formwork intersected by beam ends.
Felts understands that one dry spot in the slab doesn t mean it is ready for the finished floor.
These factors can introduce a lot of moisture variability across the floor slab.
To test for an incompatible product on the slab an easy method is to put a few drops of water on the slab.
That s why builders rarely install 6 mil poly on top of a slab.
Wall measured through slab.
Because concrete likes water the drops should absorb into the slab.
