[sara2020]

Hi there
We recently moved an older house to our land and dug and created an ICF basement. The house came with a sun room that is 6’ deep. They had to remove it for transport. we decided to make it bigger so when we made the basement, we made it big enough for the addition. Well now that it’s on there it looks Massive and I’m really second guessing. We were going to frame in the rest of the sunroom space between the old sunroom and the house but now I’m wondering-
Would we be able to push the sunroom closer to the house so it wasn’t such a massive addition and make a deck over top of the basement foundation that would be open? Would it be crazy hard to waterproof and insulate? Or is it even an option.

 

[chandler48]

Can you post pictures of what you see, so we can see it, too?

 

[Nealtw]

Yes we have done that but you likely need an engineer for the beams you have not planned for.

You build the deck with 1/4" /12 slope with 2x10s and strap that the other way with 2x4s so you can add venting above insulation.

They usually get a solid surface roof rated vinyl decking and we did one that got a waterproof membrane and 3" concrete on top.


They usually call them the wine cellar

 

[House Designer]

If your joists will bear on a treated sill plate that rests on top of the ICF wall in direct contact with the concrete, you should be good.
If your joists will hang from a ledger board, it is a little more tricky because the ICF foam spaces the ledger board away from the concrete and puts the screws in serious bending. In this case, it is better to cut away the ICF foam and secure the treated ledger board directly against the concrete cores with Tapcons.