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Can Porcelain Tiles be Installed on a Pedestal Floor System?
QUESTION
I have heard that tiles can be installed a raised pedestal floor system on an exterior application, so that it will be level and it will allow water to drain below it. Can porcelain tiles be installed this way?ANSWER
Historically pedestal floor installations were used to install 2" thick or thicker precast concrete pavers or natural stone tiles. The floor could be level and the gaps between the pavers would facilitate for water to drain below. The substrate beneath the tiles would be properly slopped to a drain with a waterproof membrane over it durable enough to take the weight of the pedestals with the weight of the tiles and the foot traffic it is subjected to. The tile industry is working on developing a pedestal installation standard for 2cm thick porcelain tile, but at this time there is not standard.The key to the installing a 2cm (3/4") porcelain tile is that you should install them on a plastic tray that sits on the pedestals at each of the 4 intersecting tile corners. Sometimes there will be an added pedestal under the center of the tile. The pedestals are adjustable and somewhat self-leveling, but you do have to add shims for slight adjustments because the pedestal cannot wobble at all. The waterproof membrane has to have a high Shore A hardness so the pedestals don't sink into it. The concrete substrate should be sloped 1/4" per foot to a proper drain with the capacity to take the potential volume of water from rain and washing down. Critical to the installation is making sure the perimeters of the installation are well anchored in place to constrain the tile assemble so it can't push out as it is subjected to different concentrated loads and traffic.
It is important that the end-user monitor the floor and if they get any wobble tiles they need to repair them immediately or someone could be hurt. For hurricane climatic conditions there are pedestal anchor systems that can lock the tile down so it can resist the uplift of wind.
Hello,
I bought a newly built house approximately one and a half years ago.
There are 9 tiles in my master bedroom that are making a cracking sound when you walk in them. The tile company came out to remove the improperly installed tiles and replace them with new tiles.
When they took up the tiles, I was advised that they never placed gator mat below the tiles and would need to remove all of the tiles.
A friend who is a contractor recommends that I don’t proceed with a full removal of all the tiles and only replace the nine tiles that are loose.
Are reluctance to removing all the tiles is it’s going to cause a huge mess.
What do you recommend?
Chances are that tiles making noise are installed on an unstable substrate or the tile is not bonded adequately. If there is a wood subfloor then it could be the plywood is making the noise.
Gator mat is not a normal tile installation product. The manufacturer claims that you can use it as a crack isolation material, but their data sheet does not say it complies with ANSI A118.12 for tile crack isolation membranes. If you don’t have in-plane shrinkage cracks and don’t expect to have in-plane shrinkage cracks then there is no need for it.
If the rest of the floor is in good shape, then all you might need to do is stabilize under the removed 9 tiles if possible and re-install them. Or if in fact there is evidence that the rest of the floor is defective in some way, then you might need to replace it.
There are much better liquid applied crack isolation membranes that do meet ANSI A118.12 and A118.10 that are also waterproof membranes that would be better to use and easier to apply if in fact it was necessary to replace the entire floor.
Can I install carpet over porcelain tile? I
Recently installed porcelain tile as I was having problems with moisture in slab. I am having major knee problems and can’t handle the tile. Can I put down carpet over the tile?
You can practically put carpet anywhere, but if you have an underlying moisture problem it would not be a good idea to cover the tile with carpet as carpet is moisture sensitive. You can always put down floor mats, throw rugs, and runners on the floor to give you a cushion feeling. That way the floor is still able to breath if there is an underlying moisture problem.
Regarding bathrooms, what size of floor tiles would you recommend to avoid water ponding? We have a project where 750mm x 150mm tiles are required, and we are currently facing challenges in sloping the tiles towards the floor drain
750mm x 150m is 2′ x 6″; or if you meant cm then is 4′ x 2′, which is more common size these days.
First of all, the key to establishing a properly slope on a shower or bathroom floor is to make sure the substrate to which it is being installed on is properly sloped with a tolerance no greater than 1/8″ in 10′ (3 mm in 3 m) or 1/16″ in 24″ (2 mm in 610 mm) . Of course the slope has to be toward the drain recommended in showers at 1/4″ in 10′ (6 mm in 3 m).
It is best and easiest to install a trench drain along the back shower wall so it is easier to have a slope. If you have an area drain in the center of the shower it isn’t easy to create a slope from all 360 degrees around the drain unless you have a small mosaic tile. Some people will cut the tile into diagonal shapes around the area drain so water slopes to the drain when it gets to that point, but you won’t have a uniform slope that might not be very comfortable; particular for a handicap shower.
I had a new wet room installed five years ago and the gray tile in some places are turning white. Can you tell me why and what the solution is to fix it please.
When there is a problem it is never due to a single deficiency, but rather due to multiple compounding deficiencies. The white tiles is a symptom of a problem, but that doesn’t tell you want caused the problem. So you have evaluate all of the components of the tile installation and the conditions to which it is being subjected to.
We need to know what type of tile is it? Is it a natural stone? If so what are the physical properties of the stone that vary not only from different geological classifications of stone, but within the same geological classification the stones have have different physical properties. In this case we would want to know what is the absorption of the tile?
We also need to know what is the tile assembly and what type of substrate was it attached to? Is this an on-ground concrete slab substrate? Is the tile bonded to the slab or is there a mortar bed on the slab, or is the substrate a plywood subfloor? What was used to bond the tile to its substrate? Was there a waterproof membrane within the tile assembly?
What are the climatic conditions in the area? Does it rain a lot? Have you seen a correlation to the weather where the white condition developed or became more pronounced?
Chances are you have a porous stone where moisture can migrate up through it. The moisture is likely coming from the substrate below, unless the substrate is a suspended slab or a plywood substrate. The surface of the stone is going to be warmer that will drive the moisture to the surface. The moisture in concrete substrate, or in the mortar bed, in the setting materials and in the stone have naturally occurring minerals. Minerals are forms of salt. So the minerals dissolve in the moisture and the moisture migrates to the surface of the stone where it then principates the minerals leaving the whitish material.
Sometimes if a stone is sealed with a non-breathing sealer the moisture gets trapped under the sealer and can turn white in spots. It normally doesn’t happen with every tile.
If this is a typical efflorescence residuals it might be cleaned with diluted vinegar. Test a small spot first. There are products sold at tile stores or home centers for removing efflorescence (if that is what you have).
Once you remove the whitish efflorescence you only removed the symptom of the problem and didn’t fix the problem so it doesn’t reoccur. You have to find the source of the moisture and redirect it. Sometimes you can seal the clean dry stone with a penetrating sealer and that can help, but that is only a temporary solution.