Dear Miss Sandeman,--The Collected Letters of C. S. Lewis, Volume 2 (HarperCollins, 2004), 788; emphases original
I think that about Houses the answer is this. Nothing rises again which has not died. The natural and possessive love for a house if it has been crucified, if it has become disinterested, if it has submitted to sacrifice, will rise again: i.e. the love for a house you were willing to give up will rise again. The willful, grasping love will not--or only rise as a horror.
About the house itself, if the love rises, then all that is necessary to bless it will, I believe, be there. It may not be very like what you would now call a 'house': but you'll see then that it was what you really meant by the house.
But the whole point is that you can keep forever only what you give up: beginning with the thing it is hardest to give up--one's self. What you grab you lose: what you offer freely and patiently to God or your neighbor, you will have. (Your heavenly library will contain only the books you have given or lent! And the dirty thumb marks on the latter will have turned into beautiful marginal descriptions--I'm joking of course, but to illustrate a serious principle).
C. S. Lewis