We did a renovation yrs ago and all of us had to stay in one room of the house (and 1 bathrm). The rest of the house was off limits (boarded up) for 8 plus weeks. It was insane. I stayed calm and told the kids that it was just temporary. If I kept calm...they kept calm. My husband was extremely calm. It was his idea to do all of this in the first place.
In fact, I told them that this is how their Grandma lived for a few years (Which she did). Grandma had 5 kids and had to live in a small space for a few yrs until they could afford an apartment. So, my kids reported back to Grandma...and told her all about our one room house...like she once lived in.
As far as the dogs go (I love, love, love my dogs)...I gave them a nightgown that I had slept on the night before. I learned this trick from a dog loving friend. And, I made sure I had a few non-choking bones they could munch on. We had leashes and walked the dogs as much as possible, too.
Make a paper chain w/ tape. Put at least 14 links on it.( Keep a bedtime routine, too). Have your son take a link of each night so he will have a visual as to when you will be going back home.