just ordered that book, which I've heard a lot about but haven't read. Thanks, great suggestions (and I am spatially challenged!)

In our old house we had a 3 car garage. I taped out the kitchen dimensions there, then taped out the counters, appliances, etc.

We also went to the annual home show with our tape measures.

If you haven’t done so, make a scale drawing of your current house including decks or patios if those are important spaces to you. I use graph paper with each block equaling a foot. Then walk from room to room in your house and think about how much space you want compared to what you have now. A current powder room for example might be the right size but you may realize that you want a couple of more feet on either side of the bed in your primary bedroom. In other words, determine how big each room should be in your dream house not just a guess like “I think we want 500 more square feet.”

@khrisz thank you - great advice! Having lived in our current house for 17 years we know exactly which rooms feel cramped and which ones are big enough.

The problem with measuring any rooms is the same room can feel cramped in one house based on how its laid out and how it relates to spaces around it and another room could feel positively roomy.

As an example, my neighbor built a house that is over 3200 square feet with a large downstairs but because of how the public rooms are arranged, it feels quite cramped. Hope that makes sense.

Definitely read The Not So Big House.

One way is to have a floor plan drawing of your existing house to compare to the floor plan of your future house, room by room. Make sure the floor plans are the same scale or your dream house may be more of a dream than you realize.

Another way is to determine ideal furniture layouts for each room and design the size of the rooms accordingly.

I had one client use garden hoses to "Draw" full size the walls in his and his neighbor's back yards flat area.

One client drew it out in the snow full size.

@Mark Bischak, Architect well this is in Florida so garden hoses will be easier to come by than snow! I love the idea of doing the floor plan of our existing house since I am spatially challenged. Thank you.

We layed out our kitchen in our current great room with landscape marking tape and masking tape. Used it to work on the flow and layout, and get a good sense of scale. We also used rooms in our current house that had similar dimensions. And I taught myself 3 or 4 different software packages to create virtual walkthroughs and renders. :)

Start by measuring your existing space and taking note of how the rooms feel. So you know that X room is 12' x 10', if you see similar dimensions you can go "oh, that's like our X room!"

As others have said, map things out to scale.

But when you get to the point of refining designs, I think it's super helpful to draw out a life size floorplan. It helped us a ton. More here: https://amodernmountainhome.com/2020/08/03/life-sized-floorplan/

@amodernmountainhome this is brilliant, thank you!