Sorry, picture didn't upload the first time

Since we don’t know what you want the extra space for, making a bigger kitchen or adding on a guest suite, etc., I wouldn’t immediately default to changing the look of the front of the house, I’d explore adding to the rear of the house. Or if that wasn’t feasible, I’d consider adding a garage side shaped wing to the left. But again, that’s only based on what I think would look nice, not what the addition is needed for, or where it’s needed.

Here are other Cape Cod-style homes that have larger foot prints compared to yours that might supply you with some inspiration. You'll be finding an architect to do this correctly.

Use graph paper at this stage to draw up and post your existing floorplan. With lots of measurements and at a large readable size when clicked on. And/or look at this software. Home Designer Training Videos (homedesignersoftware.com)

House is on a basement? A slab? Do you have a septic tank? Age and location of house? Perhaps your wife can network to get a local structural pro to stop by for a looksee as to what is actually doable and how much some designs might cost as opposed to others.

What are your goals? Larger kitchen? More storage? Additional bedroom? Family room?

I wou think your wife could sketch out several ideas

First, you address the 'why' of you want an addition, then you determine the best way to achieve a solution.

Seek local professional help.

Such a classic Cape Cod home. Definitely determine your goals first, then retain an architect to figure out the best way to achieve them. Tread carefully so as not to re-muddle the house, but have the addition compatible with the style, like the photos that Bev posted.

I would think that the first step is to determine if you actually can extend you house 20 ft in whatever direction. Of course if you are on a huge piece of property, that may not be an issue ( but I can see other buildings in your pictures ). Many towns and counties have change the set backs for building. Do you know where all ultilities are located? ie water supplies/wells, underground electrical , if any, septic tank/ sewer lines , etc. Moving or relocating these items will be much more expensive.

I would start there, then look into your materials. Roofing prices should be easy enough to find online or at a lumberyard .

Sounds like a great project!

Good luck

Not sure if your addition idea needs to be at the front, but maybe give more detail on what the space would be used for and where it makes sense to have it attached to your home. In our last cape cod, we were able to add onto the back side in the center, a wonderful addition upstairs supported below with a full season sunroom.

If your wife can’t sketch out the home, and property, to scale, with setbacks and obstacles indicated, then you have major title act issues.

Beverly showed you some great, well done additions. However, step one is researching your property and your town rules. You can’t just “add on” is most towns, so take the time to go to the building department and find out if there are any restrictions. Or hire a local architect to do the work for you. It may affect your dream design considerably and you will need to be creative.

Start with an architect.

IMO the first step is to decide what you need the addition for, that will often decide where it goes. Then talk to an architect . I am a designer but still would use an architect to add on to a house. Additions to me need to look like thye were always there and that takes skill to get right. So share the to scale floor plan now and the plan you have for the new space if you want any help here.