I used the same technique to create the area carpet as I did to create the individual rugs. To do this, you need two things: a professional quality photo printer, and some flocked paper. For my projects so far, I've used velvet paper in "coconut" from Sew Easy Industries. This is a scrapbooking product, as far as I can figure out, but it's available from Amazon. It's a bit pricey; a dozen sheets cost about 20 USD. However, if you're creative about placing your designs on your sheet, you can get a fairly good use out of each one.
This is the pattern I used for the floor. It's created from a picture of an actual rug, which was then cut in such a fashion that it'd make a repeating pattern when matching tiles were placed next to each other. I had to play around with the size, a bit, to find something that worked. Sometimes, knowing on an intellectual level that something is x number of inches/centimeters doesn't compensate for actually seeing the pattern in situ. Hint: print out one or two test designs on cheap paper first. In other words, don't be an idiot like me and go wasting the expensive paper.
|Use this if you'd like.|
I was able to fit three tiles per sheet; then, I began the somewhat laborious process of cutting each pattern area out from the larger sheet and then cutting it, specifically, to fit its space in the room. I tacked each tile down with double-sided tape for easy removal; accidents happen, and being able to take out a single piece to replace it is a great deal easier than ripping out the entire carpet! Moreover, the ultimate owner of the house may hate the design and wish to swap it out entirely. Who knows.
I searched for years--unsuccessfully--to find printed area carpet for my dolls' houses. I'm sure that it's for sale somewhere, just not anywhere that I've been able to find. I recommend, when making your own, searching the fabulous world of the internet for pictures and familiarizing yourself with copyright laws. The general commonwealth jurisdiction rule is usually some version of, the picture becomes "yours" when you use it to create a new and original artwork. However, this being obviously not legal advice (although I am an attorney (barrister) by trade, originally), you'll want to consult the rule in your own jurisdiction. Alternatively, you can draw your own design and scan it (which I've done as well).
I recommend, before embarking on all this laborious cutting and fitting, that you have several cups of whatever thinking juice (coffee, tea, Red Bull) you prefer.
For smaller rugs, the idea is essentially the same. I've found that the shorter pile of the velvet paper is more in keeping with the overall scale of the house than what's sold as 1:12 scale "area rug", and have been quite pleased with my results. However, two problems arise. One, the paper does tend to curl up at the edges a bit. I've solved this problem with tiny bits of double sided tape, or Museum Wax, at the corners. Another issue can be the white cut-away of the paper being visible on the sides. This, too, is easily solved by angling a marker in the appropriate color and running the bottom of the paper along the sides. You'll want to hold the paper at about a 45' angle to the marker, so as not to get ink on the pile itself.
|The carpet, being laid.|
|And here's the bathroom window, before installation.|
So that's it.
Further reading on the copyright issue can be found here. The case in question, which is fairly well known, arises out of Indiana (and can provide useful guidance for inhabitants of all commonwealth jurisdictions). There's also another, similar case against eBay although that's less useful in terms of guidance for actual miniaturists as it has to do with holding a third party seller liable for not removing listings. Generally (again, NOT legal advice), the danger arises when a miniaturist's activities in some way a) make the copyright/trademark holder look bad or b) siphon off a portion of potential profits. This is a very funny case, which illustrates the point. I remember, a few years ago, Hershey filed against Aztec Imports for unauthorized use of trademark (i.e. Aztec didn't pay for the appropriate license, if I remember correctly) but have been unable to find anything indicating this online.
And finally, please read one of the first cases I was assigned in law school. But make sure that you don't have anything in your mouth, first!