We are getting ready to reroof and will probably go with foam. We also want to upgrade our electrical. We were under the impression that this should all be done before we reroof. However, one contractor said we should do it after instead of burying everything and then having to dig in the roof if we have problems.
We also have some copper pipes running over the roof and during the summer, the water is absolutely scalding. Naturally, the reverse is true during the winter. I wanted to put the water pipes under the foam but this contractor didn't recommend it.
I'd appreciate any help in trying to decide what order in which to do these things.
Personally I would fix all the electrical and insulate the pluming before the roof is foamed over. I prefer the protection of the foam roofing material compared to ease of access. Basically there is enough stuff to trip over on the roof and when you fixing leaks or other things, having less things laying on the roof would be better in my opinion. Also you will need to make a new hole for every electrical access into your house creating a new possible leak location in the roof if you do it afterwards. And besides, once you get new electrical you should not need to access it for the next 50 years :->
Before. If you're concerned about access to electrical, one of my neighbors had the electrician install conduit pipe about a foot above the roof at each junction box. The roofers then foamed around all the openings. This way, if there's a problem, you still have access through these exposed junction boxes.
The idea is correct - but the terminology may be improved if you tell your electrician that you want "pull boxes" at the end of each conduit. Also be sure to use large enough conduit so that you may add additional romex (vs. replacing the existing cable) down the line.
Thanks, everyone, for your advice. It's really helpful.
Re plumbing, should I ask for an access junction (or whatever it's called) also?
Plumbing is better insulated under the roofing and the sewage already has a vent pipe for access, so I would not worry about the access for plumbing. You can always use a metal detector to find stuff if you need to. Again its better just to have it done right before you roof and then don't worry about it.
Junction boxes are a fine idea if you plan to expand your electrical later but its better to just have it done right the first time because expanding electrical involves taking out the walls in the house as well so just do it right the first time and bury it in foam to protect it and so you don't need to worry about roof leaks which is much more likely.
If you want you can take pictures of the roof after the plumbing/electrical is done and then map everything out marking distances so you know where it is in case you need to access it.