Technically anywhere there is a change in substrate or backing surface such as the joint between walks and floor and wall joint caulk should be used in place of grout since these surfaces move independently of each other but the tcna then goes on to list five reasons that installers use grout instead of caulk.
Should i caulk between floor and walls.
When this occurs whether the homeowner understands the physics behind it or not his or her first impulse is often to plug the gap between floor and wall typically using hydraulic cement or some other waterproof sealant.
Since sanded caulk can crack tile and other materials when it expands in too small of a space unsanded caulk should be used to fill tight joints that are smaller than 1 8 inch wide.
Caulking this connection is fine if the wall is some sort of one piece sheet or enclosure but with tile it should not be there.
Caulking is an easy remedy to fix the gap between the wall and the subfloor.
But on that subject the tile council of north america tcna offers the following recommendation.
The tile council of north america recommends at least a quarter inch gap between the tile floor and the walls.
Grout is not flexible so it s not the best material for the job while caulk allows for movement and also provides a better sealant.
The grout joints are designed to prevent water from penetrating the wall but any small amount that does penetrate is able to evaporate out and or weep out along the bottom.
Caulk should be used between the tile planes or anywhere there might be movement between the tiles and the adjoining shower surfaces.
Never fill this gap with grout because tile grout is not flexible.
Air seepage is hard to prevent especially on the old floor.
Unsanded caulk has a smooth appearance and texture.
Since you are joining two different materials together you should use caulk in the space where the floor tile and tub meet.
Instead fill it with an elastic material capable of sustaining the movement of the floor and the movement of the wall.
Caulking is the best choice for this application.
Caulk seals seams between tile and fixtures or walls.
Generally grout should be used on the shower walls and floors and all other vertical or horizontal shower planes.
It s most often used to caulk countertops and backsplash since it creates a clean finish.
Caulk should appear seamless while keeping your walls windows floors and ceilings adjacent to showers tubs and toilets safe from the excess moisture that is typical in a bathroom.
If the basement floor has cracks these will also leak water when hydrostatic pressure increases.
Seepage in spaces between the wall and the floor especially on the sagging subfloor or due to expansion of the laminate floor may be a common problem.