I decided after I had described my nappies last time that I would do a tutorial about how to create an envelope opening for a cloth nappy. The pattern I used is the wee weka sm/med pattern, and this is supposed to have a back opening, but I prefer the envelope style.
Materials:You will need all the same materials listed in the wee weka pattern, and you will need slightly more microfleece than the size of the finished nappy.
First, fold the back casing bit of the pattern over (so its not visible anymore), as if you were making a fitted nappy. Cut out the PUL all in one piece (I didn't take a photo of this).
Cut out the microfleece until after the leg elastic markings on the pattern. (Check out my awesome pattern weights - they are J's wooden ark set, much cooler than the tin of salmon I usually use).
Note: I usually make my opening just after the end of the leg elastic, because I find that the most economical use of microfleece. You can have it anywhere, but if you make the opening where the legs will be elasticated, then it is going to gape open.
Next, lay the cut out piece of microfleece over the top of the rest of the fleece. The amount of overlap is up to you. If you want to make sure that the microfleece will cover the insert when the nappy is stretched out you should aim for probably a couple of inches.
Place the pattern back over all the microfleece so that everything matches up and cut out the second part of fleece.
You should now have two pieces of fleece that overlap to form the inside part of the nappy.
Next, baste the two parts of the microfleece together (I used my machine, but you could also do it by hand). This is to make it easier to sew all the nappy together.
The opening works better if you have the bigger piece over the top of the smaller piece.
Follow the pattern instructions for adding snaps or velcro to the PUL.
Next sew the PUL to the microfleece, right sides together. Because of the envelope opening, you can sew all the way around the nappy.
Attach the leg elastic as described in the pattern instructions. Attach the back elastic in the same way - use the back elastic markings on the pattern as a guide.
Turn the nappy in the right way, and attach the snaps/velcro to the wings and you're done!
You could modify almost any pattern that has a back opening into an envelope opening using these instructions. If anything is unclear, just ask and I will clarify things.