We don't use one if its a good pitch. We are quite happy without if we can and prefer to respect the grass. (don't like hard pitches). if we are pitches for a reasonable period we may run a lawn mower round the awning!
If you want one a tarp is probably good value for a short while. Some of the breathables generate a lot of worm casts.
We never use an awning groundsheet, even in our full awning. I can't honestly see the point - non-breathable groundsheets kill the grass, are a pain to clean if the weather is anything but perfect and always feel damp and cold in the morning when the weather IS good, because of the dew and condensation. And breathable groundsheets let grass and moisture through (if they didn't , they wouldn't be breathable!), so why bother?
I'm with Scampi; I don't use a ground sheet with either full or porch awning anymore.
I used to, but now don't see the point, other than if your stuck on a seasoned grassy pitch, maybe you wouldn't want to mow in the awning.
I must be in a minority , I use a proper waterproof non breathable groundsheet and always have. Some sites I've been to the ground is very muddy when it rains , and they allow normal groundsheets .
We got a breathable one froma site recommeded from here (but I can't remember which one it was sorry). Got an 'off cut' which was still big enough. Although breathable the weave was tight enough to stop worm casts. In france some of the sites were a bit hard and they did say an undersheet is good to use then but we didn't bother and the groundheet was fine.
If we are on a hardstanding we don't bother with a groundsheet but if we are on grass we use a one. We got a breathable one with our caravan which i've yet to use so can't say how good it will be
We bought the Kampa breathable Easy Tread Carpet. It's fine except the first time we used it at Easter when the ground was quite wet we did get wet socks when walking on it (no wormcasts or anything else though). Having searched on here I have found that it goes with the territory. It's good on hard standings though - makes it easier to walk on bare footed. Dry grass was no probem ! We bought the 250x250 for our Kampa Rally 260. I found that if you peg out the mud flaps inside first then the awning carpet fits over the edges of these.
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