OT: Roof framing, alteration Options

[thomasotten]

I have an existing roof on my house that is pitched and creates a cathedral type ceiling underneath. I am considering increasing the pitch of this roof, for ascthetic reasons mostly, but also to add insulation to the roof, which I don't thick is adequetly insulated. There is no attic space right now, so I cant' be sure of the insulation, although it gets hot in summer time. I want the final roof to be 12/12, and to do this, I would need to raise the ridge by about 2'. From the ridge, I would then run rafters down to the bottom of the roof fascia. Instead of raising each rafter up and causing a mess, I am considering building a structure over the exsiting roof, and then sheathing over. That way I don't disturb the ceiling. I was thinking of also doing this in phases, keeping the existing shingles on as a I go. What do you think?

[rick 918-S]

Better check local buillding codes. Around here that would not be allowed. Fire codes wouldn't allow a roof over a roof. It traps smoke and fire causing danerous conditions for fireman.

You may be able to tear off 4' at a time and add a room and attic type truss. This will give you the added pitch your looking for (12/12) and a bonus room with a second floor.

The fact that you now have a cathedral type ceiling now doesn't mean you can add a second one over it. There is a lot of stress pushing out on the tops of the walls with this type of construction. Adding weight just increases the amount of force pushing out on the tops of the walls. This could cause a collapse. I've personally seen it.

Also depending on the type of weather you have, if venting is not proper condensation will rot the roof deck and ridge beam, seen that one also.

As an insurance adjuster... this type of claim may not be covered.