Can your mom afford to hire people to do this work? If not could you and your brothers pitch in to have a budget for it?
I think your husbands request is very fair. Not only is he going and helping over there (a whole lot) but it does take time away from your own children.
An hour away is 2 hours travel.
Maybe he could make an agreement to weatherize her home in the fall and then take it all down for spring, but other than that she needs to find someone in her on town.
Maybe you could assist her is making a list with numbers of who to call.
Just sit down and explain it has been an honor to help your mother and you still all want to help, but now that you all have 3 children a home, it is becoming harder to help and you are feeling guilty about it.
But you have some suggestions,.
This is just a suggestion ~ Also let her know that as your children are becoming more active with outside activities, you would love for HER to start coming to your home to stay over night once a month and just be able to relax and visit with all of you.. (this will be helpful when they start team sports)
Anyway, living close to family is such a blessing, but it can be like a curse.. (both of our families are here only 20 minutes away... The ENTIRE family.)..
No guilt, just thoughtful honesty... She will understand..