70's Carpet underpad

So I am in the last steps of renos after buying a house in December, and the last thing on the list is flooring in the tv/dining room. I started to pull up the carpet yesterday only to find the original green swirl carpet under it and when I cut a hole it in I found black underpad that looked solid, but as soon as you scrape it, it turns to a fine dust, almost like flour. So now I have 600 sqft of this to deal with, just when i thought all the head aches were over lol. I guess my only solution is to peel the green carpet back a foot or so at a time and hit it with a floor scraper and shop-vac, it is going to make a hell of a mess though. Has anyone else come across this?

Wet the carpet down first. It will mean a little more scraping on the underpad, but will keep dust and clean up to a minimum.

Yes! just did this with my house from the 80's with original carpet in the bedrooms. I put on a mask, and taped off the area with throw sheets (drop clothes) and then pulled it all up at once. I then vacuumed the entire area and wiped down the walls.

It's not as clean, but much, much faster.

FishFrenzy

Yep had this with the only room in our house that wasn't re-done when we bought it, pulled carpet, then another layer, then the black pad, hit it with the scraper and poof, dust. was a mess.

Awesome, thanks for the water tip Blue, hopefully that will help with the dust. I didnt plan on doing that floor as the carpet was in pretty good shape after we steam cleaned it, but the Flooring we got from Costco that we did the hall way and bedrooms in was on sale so we thought why not, I wish i had known before, it would have been the first thing out before the rest of the room was re-done and there wasnt a mess to worry about.

Had the same thing in a few rooms doing my Moms' place. I sealed off each room and went at it with a mask on. Scraper and broom and dustpan for me, and cut the rug in 3' wide chunks, rolled it up, and wrapped it in thin poly before taking it through the house to get rid of it. I had to mop the room a few times to get rid of any residual dust but I found a small fan mounted in the window helped to keep the dust out of the rest of the house.
John

The joys of home ownership..... People who were just flipping for profit often used to cover up the old, instead of removing it and doing a proper job. The house we are in now was built back in the "paisley daze" when the foam back carpet was glued to the plywood subfloor. Still have a couple of rooms to do down the road...living room, kitchen, dining room, entrance are now done in poplar flooring that we cut on site and laid ourself.