Concrete sub-floor, no backer board. 40 year old 4 x 3 tiles with yellow "mastic" as the adhesive. It's caked on good underneath and it's old. I wanna prevent renting a Hilti/Kango with a scrapper cause it'll cost $100 around these parts for a day. That'll be a last resort I guess
Solvents?
And type of manual scrapers?
grinders or some other abrasive?
I can't damage the sub-floor (concrete) underneath.
Can you just go over it with new backer and ner tile/wood/carpet????
Spend the $100 on the proper tool, or borrow one from someone you know that owns one...
~~ Evan
Any alternative to the scraper is going to be much more labor intensive and time consuming.
Harry K
A five foot solid steel wrecking bar with a chisel point will do just fine and you can pick one up for probably less than 20 bucks.
They weigh about 50 pounds or so, all that force is concentrated to the tip, when you slide it on the underlayment the majority of the tiles will simply pop off. The ones that dont, hit em with the bar from the top and pulverize them.
There is no underlayment. It's a solid concrete pad. There is no basement to this part of the house. With a point I'll chip the concrete
That said everyone says use the power tool with the scraper. I guess it's worth $100 by the sounds of it.
I really wish but no. The grouting was done very poorly on this particular floor but the tiles are only 4 x 2 inches, not 12 x 12 for example. Several of the tiles are broken and many others they have become uneven. I'm putting in a duraceramic floating floor and the tile store owner and installer said the paper backer might not hold up if apply overtop of such small tiles. It'll be in a heavy traffic area.
A heat gun might help soften the adhesive, then scrape it with a wide putty knife. It all depends on the size of the floor. If its a bathroom, this should be fine. If it's a 20x 50 foot room, rent the tool.
Rent the scraper. Using it, getting the tile off will go fast and easy. I have no idea how effective it would be on the mastic itself though. In the past, I have used a torch to remove mastic, works OK but takes time.
You are going to chip and ding the concrete no matter what. Small scratches, pops, and dings will not prevent installing the next floor. The power scraper will gouge more than the pinch bar. You can use a brick set (wide cold chisel), a heavy hammer, and a face shield.
Big hammer, big scraper and some elbow grease. Crank up the tunes and giver. Make sure there's a couple of cool one in the fridge.
LdB
Even with the long bar you wont damage the concrete, chips dont count as damage, and you'll not crack the slab, also concrete with mastic on it is already "damaged".
If you a suitable sized compressor, Harbor Freight has long reach air scraper for $99.00 -- on sale.
Long Reach Air Scraper
Item # 37073
Extra wide 4" blade makes short work of tiles and linoleum covered floors. 2200 blows per minute separates any glued floor coverings quickly.
Piston diameter: 1-1/8" Air pressure: 90 PSI Air consumption: 10 CFM Air inlet: 1/4" NPT
Don't worry about chipping the concrete. If you chip the concrete, just patch the chip holes with new concrete.
John
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