Question
Hello Sean. I have rock walkway in my backyard I would like to replace with concrete. My walkway though will have a slight rounding curve to it over a distance of 31 feet 4 feet wide, 4 inches thick. So far I can't find a material that will bend for the forming support. Do you have any suggestions? Every project of this type that I have seen on the internet so far is either straight or angled. Thanks for your time. Mark

Answer
If this is one time thing you should just buy a sheet of masonite at your local home supply store and rip it into 4" x 8' pieces. Masonite bends easily but you have to screw it into the stakes as it is difficult to nail without a nail gun. The bad thing about masonite is that it doesn't last more then one or two times of use and degrades when wet. It's advantage is it is cheap. Other options I have used include Hardi-siding, specially if you wet it first. Or for a strong form use 1x4 and "Curf" the back, which consist of making many small cuts 1/4" deep, about 1/2" apart, perpendicular to the length of board. This makes it bend easier.
Lastly you can now by vinyl trim at most home supply stores it comes in 2, 4, 6, and 8" widths and last for many pours but is very expensive.

Good Luck.

Sean J Murphy, LA,ISA, LEED AP
Please check out my blogs and articles on landscape topics like this on my websites.
http://www.seanjmurphy.com
http://amenityarchitects.com