MAPEI ECO Prim Grip,ready-to-use, low-VOC, bond-promoting primer, enhances performance and adhesion of mortars to existing ceramics and difficult-to-bond-to substrates, improves bonding of self-leveling underlayments (SLUs) and bonds of render coats over cementitious substrates, easy, low-odor application 1 gallon (3.79l) jug

I've used this product twice. WOW !It allows laying tile vertically over (solidly adhered) previously installed tile.The process couldn't be easier. Cover surfaces not included in project; load roller with the product; roll onto surface to be tiled. Follow label directions for suggested application and drying time and clean up. Once dry surface will feel gritty. This is the magic ingredient that allows you to tile over original, existing tile. Yes, this creates some issues with side views of the double thickness. Creativity will get you through this obstacle. Possible solutions to cover tile thickness with plastic or metal moulding or "hiding" the thickness by packing additional grout along these "thick" edges, allowing it to become firm and beveling or tooling these edges to a bevel or " quarter round" profile.

I'm late in sending this review but wanted to send in my input. I found out about this product on You Tube from a guy who reno's homes. He said this was so much easier than pulling off old tile - just paint this stuff on, allow to dry, then tile right over the existing. My local Home Depot or Lowes said they could not carry it in Alaska due to shipping constraints. However, once again, Amazon comes through. Now the packaging says not to ship or store in freezing temps. However folks, anything sent to Alaska is going to freeze, but I took a chance anyway. I'm re-tiling a fireplace and didn't want to chip all the old tile off the wall and re-sheetrock. Got the product on my doorstep and by the time I got home it was 15 below zero. I put it in the garage (about 55 degrees) and let it thaw for a couple of days. Then I opened it, stirred it, and applied according to the directions. Worked like a charm!! Saved me huge amount of time and money and my tile job and my fireplace looks fantastic. Shipping was as promised but I worked that day and just couldn't get home in time to meet the delivery van. But 15 below did not interfere with the product's ability to perform - if allowed proper thaw. This stuff is fabulous.

This product works great and I found out about it from a random YouTuber. Put this product down before tiling to get a textured and grippy surface for your tile thin set to adhere to. This stuff sets up quick and feels like concrete once dry. If you are doing a tile backsplash on drywall, I would definitely consider using this product.

Works really well

Refinished 1980s melamine and this primer did it! My natural stone backsplash adhered along with the thin set.

Works as described.

The bathroom came out great but it was way more work than this product advertised. Again the shower came out great! It looks like it was retiled.

Used this over a very glossy porcelain tile. Cleaned the tile and painted this stuff on with a roller. Tiledover tile with no adhesion issues at all! Works great.