Q:

Can I get Illustrator to save an SVG and retain a transparent stroke?

Below is an icon comprised of two images. The top image has a 1px transparent stroke "knocking out" the layer below. This is fine as an .ai file. 

However when I save as .svg the stroke has disappeared.

Is there any way of saving an .svg file and keeping the transparent stroke masking the layer below?
Thanks.

A:

It is a better idea to actually change your shapes—cut out the enlarged flag shap from the house shape:

Select your green flag shape;
Remove all strokes;
Choose Object > Path > Offset Path... and choose an offset value;
This creates a copy of your flag shape, enlarged as if it had an incorporated border of the thickness you specified. Select that shape (it's selected by default if you exit the Offset Path dialog box);
Also select your house shape (Shift+click on it with the Black Arrow tool (V));
In the Pathfinder palette, click on subtract.

This way, the house shape is actually changed, and the knockout effect will show up in any kind of file.

