There are different kinds of landscape fabric. Some is thin plastic and tears very easily. I can't see that it has ANY use. While no fabric protects from weeds, the tough woven polypropylene does have a valid use as a soil separator, keeping gravel mulch separated from the soil. Deal with weeds by pulling or with chemicals. Newspaper or cardboard absolutely would not work as a soil separator.

Why are you using gravel instead of a thick layer of wood based mulch which won't need a separator fabric, and would only need dressing every couple of years -- or less -- below a deck?

I've used the smallest size bark as a barrier. Wet it to make it settle a bit then put the gravel over it. Eventually if I do get weeds I use a little Ground Clear solution. Under a deck that should not be a big problem. The neighbor put heavy landscape fabric down under bark next door and it's exposed now and flapping around. It never stays put and seems like a waste (to me). I've also seen thin cork on a roll used under gravel for paths. It adheres to the soil and decomposes over time.

The separator fabric serves two purposes: stabilizing the base for the gravel mulch (which is not really important since it will be below a deck, and therefore without traffic) and it allows for clean removal of the gravel at some later date should it ever be decided it's no longer wanted, or if some type of repair must be made requiring excavation below it. It is not, over a period of time going to help with weed prevention. Lack of light below a deck and the gravel itself (a little) will help with that. Any weeds that infiltrate (there won't be many) can be pulled, chemically removed or ignored as the owner sees fit. To use something that will decompose as a separator will not help at all with the later removal of gravel if it is ever decided to get rid of it. Also, it will not help with weed prevention. What would be the point of using something that decomposes? (Unless the entire mulch is biodegradable and the "separator" is used for initial weed "smothering" purposes?)

Jana, I definitely agree~landscape fabric is useless! I had my complete backyard dug up 2 years ago and replaced w/8" of mulch, w/the fabric underneath. I thought for sure the weed problem would be eliminated, but it ain't!! I've pulled all the fabric away with the help of my grandson, and am now laying down cardboard, in hopes of blocking out the light that seems to keep the weeds growing, and growing and growing...you get the picture!

My sis used a rug. She cut it up in pieces and used it where necessary~hasn't had a weed under the trees since! If you are planning to plant w/the carpeting 'installation'. you'll have to cut a hole where you want a plant.

we have used old carpet turned upside down in the dirt- works very well and should last forever under the deck.
i agree- the landscape fabric is a waste of money and a lot of trouble in the future. min