Unlikely to cause the foundations any problems, but given that it will want to get 8 feet by 8 feet, and its in a small bed, unless you want to keep it hacked back, I'd change it for something smaller anyway.

Difficult to get rid of this plant once you have it.....

root spread tends to match the spread of the top growth.

Many thanks to you all for this info- very useful L.

we just dug up 2 bushes that had grown 10 feet tall because of water issues and the root was about 3" in diameter. It had ran the nearly the entire length of my 60 ft home and underneath the concrete slab. I would suggest if you plant bush do away from concrete slabs, french drains, septic systems or field lines.