If you have to place your new parquet on a layer of existing ceramic tiles , make some considerations.
I state that the range of products that identify with the generic term “ceramic tiles” means various types of materials: the recent porcelain stoneware but also the “old” single-fired and double-fired tiles, and the Tuscan terracotta.
Each of these has different characteristics and when I do the inspection to verify the feasibility of the intervention, I take it into account to suggest the most suitable installation solution for the situation.
For example, single-firing has a superficial enamel better penetrated than double-fired enamel. Both are less compact and vitrified than porcelain stoneware (it is valid both for the full-body stoneware version and for glazed stoneware).
PORCELAIN STONEWARE: CHARACTERISTICS AND DIFFERENCES WITH OLD TILES
Laying the parquet over the ceramic: when is it possible?
Once the type of product has been examined, the same analyzes must be carried out as are necessary for a screed . The humidity must therefore be examined, the presence of the vapor barrier must be checked and any possibility of water infiltration (or creation of condensation) in the screed below the tiles on which the wood is to be glued must be excluded.
Attention should be paid to the “dew point” phenomenon whereby if the ceramic floor is laid in a room on the first floor (warm) and under this room there is an uncovered porch (cold) it is necessary to isolate the attic with a coat . thus avoiding the formation of interstitial or superficial condensation that would damage the wood.
Parquet above the tiles: which installation?
At this point I will recommend glued or floating installation .
Clearly the floating pose better tolerates stressful situations, so if there are any problems I will push in that direction. I remember that the floating installation requires expansion joints (or better contraction) that must be carried out even in the case of overlapping on a ceramic floor.
As I always tell customers:
The floating pose forgives, the glued one does not.
LAYING OF WOOD, GLUED OR FLOATING
Bonding of parquet on tiles: necessary precautions
If the conditions are good you can opt for laying with glue.
But to be able to realize it, 4 pre-conditions and some precautions are needed .
Let’s start with the preconditions:
► The tile must have been laid in a workmanlike manner, with perimeter and central joints
► There must be no tiles that sing in vain, they must be well glued and cohesive with the screed. If there are too many tiles that sing in vain, it must be demolished
► If most of the floor has been subjected to cuts to allow new systems to pass through, it is convenient to demolish the remainder and make a new screed.
► The humidity present both in the areas where the traces were made for the systems and below the tiles must be evaluated. For the purpose of this latest assessment it will be necessary to demolish some tiles and perform the analysis on the underlying layer with an electric hygrometer and, in the case of doubtful values, with a carbide hygrometer.
laying parquet on tile floor
Bonding of parquet on tiles: necessary operations
Once these preconditions have been verified, the detached tiles are removed and the remaining space is shaved (quickly dried), the traces are closed and finally an adhesion promoter is spread over the entire surface.
The adhesion promoter increases the adhesion capacity of the surface and is usually mandatory in the case of ceramic tiles.
The possible need to carry out, before the drafting of the promoter, an abrasion of the surface using a machine with diamond nails should be evaluated. This mechanical operation is intended to break the glaze and increase the ability to grip.