New Portico Framing Into Existing Roof

Now take the 4x4 beams and erect them to the perimeter outside the porch about four feet apart.

New portico framing into existing roof.

Make a cutting on one of the sides of the horizontal roof beam on an angle. Using two inch by four inch studs build a frame for columns that stand from the porch floor to the soon to be built roof. Butt the first new truss against the old one. First the 4x4 beams need to be cut to the size of the existing roof so the porch roof and the edge of the existing roof will be even when the job is complete.

After you shingle the roof with step flashing adressing that wall intersection tuch taarpaper under the existing tyvek and over the step falshing then re install the siding trimming it to about an inch above the shingled roof. Blind valleys simplify framing. Then mount new trusses on the new addition walls. To keep the porch roof framing as simple as possible we installed a structural ridge supported by posts at each end with the common rafters landing on top of the ridge.

This includes a material cost of 11 to 70 per square foot and 12 to 40 per square foot in labor. Tie into the end of an existing gable roof by removing existing facing boards wall siding and any other obstructions back to the first truss of the old roof. Cover the column frame with siding brick or any outdoor material that matches the exterior of your home. Allowing the siding to contact the shingles will wick or lead water back into the wall.

Tying in to an existing gable roof. You have to do it thoroughly so that the rafters sit flush on it. Brace the column frame in place using l brackets and concrete screws. Attach the horizontal beam by using a nail gun.

After installing the rafters we still had to extend the porch roof back over the shed roof creating a valley on either side. After that to make it flush with the roof of the existing house cut the two outer rafters.