Roof Over dilema ?

[SpongeBob]

Hi, older '70 MH with crown type rubber roof. No leaks. I have totally gutted the inside over the past 6 months. All wall studs are 2"x4" allowing for more insulation. New floor 3/4" T&G plywood. 1/2" Sheetrock throughout. Here is my question. The roof trusses are the original 1"x2" with the panel gussets. The original sheetmetal roof was covered by this rubber roof that has 2"-4" corrugated material underneath the rubber. I want to put a gable style roof over. I have my plans to build the kneewalls, 2 x 6 rafters with collar ties and a 2 x 8 ridge. Then 1/2" O.S.B. sheathing and metal roof. Sound straight forward so far? Here's the dilema: My first plan was to put footers with posts & beams for the roof over. Our park did not approve my plan to dig the footers. (48" deep required here in New hampshire.) So I need to build the roof over directly on top of MH. (Permit has already been approved) Because of the corrugated material under the rubber roof , must I first remove this corrugated material to get to the top plate of the walls which will support the new roof. Or am I misssing something? THANKS FOR ANY INPUT! - Bob

[Greg]

Bob I'm sure that our roof expert JD will add to this, but I would be very concerned about the weight. I would remove the existing roof, and in all likelihood add parameter blocking to support the new roof, otherwise you run the risk of actually bending the floor joists from the weight. Greg

[JD]

Hi Bob,

Greg is right. If you go ahead with this plan, perimeter piers or blocking would help support the added weight. But in NH, I would imagine that footers would be required for the piers. I don't know for sure since all of my experience is from an area without ground freezing issues.

Removing the rubber roof is a snap and wight take 2 guys a couple of hours. Cut the rubber into 15' strips to make it easy to manage.

As for as any other suggestions or ideas, I would not want to comment, because I feel that adding a 2x6 and sheathing roof to your home is a very big mistake, even with piers. If you do go through with this, I hope you get the plan engineered to be safe for your home.

Is there a reason that you would not want to consider a steel roof like the one Mark (Mr Mobilehomerepair.com) has plans for? He has stated that it will work on curved roofs. My first big job in construction was building pole barns with this type of metal. I also think that it would have no problem on a curved roof, though I have never tried it.

Best of luck to you. Maybe someone else has some ideas.

JD

[geraldk]

hi bob, i was contemplating doing the same thing as you ...BUt no engineer would sign this off because of the added weight of new roof construction Plus the extra snow load in winter time,they were scared of the walls bowing out and the roof falling down inside... and we only get between 3 -6 feet of snow up here in alberta Canada.... doin a roof like marks book shows is the way to go and will give ya good reason to do soffit and fasia and gutters so water dont run down the side of your home