No its not deprivation of assets as both owners would still own half the property. The house would still be disregarded, so no change there. The only change is when one spouse dies, because each tenent in common can leave their half to anyone they want - if its joint ownership then it goes automatically to the remaining spouse.
OH and I own our house as tenants in common and we have both left our half of the house to our children in our wills. If/when OH moves into residential care I will still be living in the house and so it will be disregarded. If the house gets sold before I die he will still get his half of the proceeds. If I die while he is still in a care home, though, he will not automatically get my share. I can do what I like with my share - my money and assets are not considered in any financial assessment of his fees, so it is not deprivation of assets. He will still keep his share, but my share will go to our children.