I was wondering if anyone had ideas or advice on building a house for family of 7 (Parents with 5 kids maybe a dog) I got like the some of the bedrooms built (I'm lazy and use the blue print but also mix and match).
But I'm stuck on everything else.

Routing matters. Floor plans, doors and furniture arrangements need to allow Sims to easily navigate the home. The same goes for pets. If a couple yet have no children (and plan a large family) I leave all but the parents (and perhaps grandparents) bedrooms vacant. Depending on room size, several children can share a bedroom. You can either set up a nursery or (if there is room) place crib and changing table in parents bedroom).

Keep in mind that toddlers can not climb stairs on thier own.

Enough outdoor space for drive way, gardening and play equipment is worth considering.

Don't over frunish or over decorate to allow the family to personalize the home over time.

I am not sure why prior post was rated unhelpful, but.... I love to build and have built maybe at least a thousand or more lots in Sims games. If you are having problems, perhaps download a large house and alter to your liking? I love to build but also like seeing what others do. And redo them! :D

I am not sure why this is in the upload section? Post some photos and if you have specific questions, ask. But how to build or decorate is really too generic as those choices are all up to us.

Thanks for helping me out, it is helpful for me. You made my day.