insulating between old shingles and ...: "Hi. Am looking to add new metal roof over existing ..." - Rod Tustin (3/31/2017) | Installation

Hi. Am looking to add new metal roof over existing shingles. Cottage has a ridge vented cathedral ceiling and I would like to add a layer of 2" rigid insulation between the shingles and metal roof. Is this a good idea? Have had some issues with condensation since new windows were installed. Thanks, Rod	Rod Tustin 3/31/2017	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/21910/find/
The house is effectively "tighter" with the new windows and you are not controlling the moisture levels. That is an issue that needs to be addressed on its own and is really separate from the roofing consideration. Next, you are mixing ventilation types here. If you are going to use foam, you would need to treat the roof as an insulated roof deck and close off the soffit area along with the ridge. Nothing about the foam or venting is going to necessarily address the condensation issues inside the home though. Those need to be addressed on their own. Are you running a whole house humidifier? If so, turn it off and bring it back online slowly. Humidity shouldn't be above 35% in the winter if you are in a colder area and even that is pushing it.	Eric Novotny An informed customer is the Best Customer! 3/31/2017	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/21911/find/
Eric I am wanting to add a galvalume metal roof to my home. My question is also about insulating between the shingles and the metal roof. I'm getting different opinions from contractors on the insulation. Some say it isn't necessary others say it is. I live in south Louisiana and don't know which way to go to insulate or not to insulate? Thank you!!!	ezenitin 4/15/2019	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/24191/find/
What is the construction of your existing roof right now? Sealed attic construction or vented?	Eric Novotny An informed customer is the Best Customer! 4/15/2019	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/24192/find/
Its vented	ezenitin 4/15/2019	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/24193/find/
If its vented, and vented well, the insulation is mostly going to serve as a leveling substrate in that case.	Eric Novotny An informed customer is the Best Customer! 4/15/2019	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/24194/find/
Thank you for the advice!!!	ezenitin 4/15/2019	Share Or copy this URL: https://www.metalroofing.com/spirit/comment/24195/find/

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insulating between old shingles and new metal roof