Question
Looks like my landscape architect might be leading me in the wrong direction.  I need a tree that will reach at least 30ft in height but not exceed 20 ft in width. They would all be planted about 10-12ft away from the house on a slope. I'm located in SE Wisconsin...would you have any suggestions of something that size, that close to the house that isn't super dense and can tolerate partial shade?  Thanks!
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The text above is a follow-up to ...

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I'm a little confused...if you should plant a River Birch that far away why is it one of the most popular trees to plant in the front yard of house, usually 10ft away.  I've seen them as close as 7ft away from a house.
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The text above is a follow-up to ...

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Is there a technique for planting a river birch on a medium inclinded slope?

Also is there a minimum distance that a river birch should be planted from the fondation of a house?  In Wisconsin I was told maintain at least 9 ft away.
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All birch trees thrive where conditions are sunny and the soil is well drained, somewhat sandy but high in organic matter. Birches do not usually thrive on heavy clay soils where air movement to the roots is restricted. On a healthy birch, the roots will spread to a distance of at least twice the tree's height. This means that the roots of a mature tree may cover an area about one third the size of a football field. To permit proper root spread, trees should be planted as far as possible from any obstruction that may interfere with root development. Sidewalks, driveways, patios and building foundations will all limit root.
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Birch trees are prized for their outstanding bark characteristics and their graceful delicate foliage. Numerous species and cultivars are used in landscapes, and almost all are distinctive in bark coloration, growth form, and susceptibility to certain insect pests. Though homeowners often desire birch as an ornamental tree, they soon discover that birch can be very difficult to maintain as a healthy, long-lived specimen. In many landscapes, birch trees begin to decline within a few years, and many trees die well before reaching maturity. A healthy birch tree should be able to survive and thrive for 40-50 years. In many yards, however, it is not unusual for birch trees, especially the white-barked birches, to die well before reaching 20 years of age.

A number of different types of birch trees are available for landscape use. Most have some characteristics that are common, including these:

Medium size, often reaching 40-50 feet in height
Yellow leaves in the fall
Available as single stemmed trees, but also as clumps having 3-5 stems.
The white-barked birch trees are more susceptible to attacks by bronze birch borer, a serious insect pest, than are the birch species without white bark (river birch, Heritage river birch, sweet birch, and yellow birch). Within the white-barked trees, our native species, paper birch and gray birch, show more resistance to bronze birch borer than do the many exotic species such as European white birch. Whitespire birch is one exotic white-barked birch tree that has been more resistant to bronze birch borer than the other exotic trees, thought it is still susceptible. In warmer climates, such as Ohio and Iowa, river birch or Heritage river birch is often a better tree selection than any of the white-barked trees. The white-barked trees are more likely to do well in cooler climates, though yellow birch, river birch, and Heritage river birch also do well in cooler areas.

If you use a dwarf variety the tree will not grow large and you can plant near houses I expect this is what is planted near the homes you have seen. One of these is

Betula nigra 'Little King' (Fox Valley)

This is a dwarf cultivar of the River Birch and relatively new. Only growing to 8'-10', it is a great tree for those that love river birch, but only have a small area in which to plant. Similar to the species in all other respects.  

Answer
I suggest you contact the Wisconsin State Forestry agency and ask one of their Foresters which local tree should you plant in that area. They can come out and take a look if you ask. The web link to their contact page is
http://www.dnr.state.wi.us/org/caer/cs/ServiceCenter/SSbyRegion.html